Commit Graph

561 Commits

Author SHA1 Message Date
Prasad J Pandit
7bd9275630 9pfs: use g_malloc0 to allocate space for xattr
9p back-end first queries the size of an extended attribute,
allocates space for it via g_malloc() and then retrieves its
value into allocated buffer. Race between querying attribute
size and retrieving its could lead to memory bytes disclosure.
Use g_malloc0() to avoid it.

Reported-by: Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-10-16 14:21:59 +02:00
Jan Dakinevich
772a73692e 9pfs: check the size of transport buffer before marshaling
v9fs_do_readdir_with_stat() should check for a maximum buffer size
before an attempt to marshal gathered data. Otherwise, buffers assumed
as misconfigured and the transport would be broken.

The patch brings v9fs_do_readdir_with_stat() in conformity with
v9fs_do_readdir() behavior.

Signed-off-by: Jan Dakinevich <jan.dakinevich@gmail.com>
[groug, regression caused my commit 8d37de41ca # 2.10]
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-09-20 08:48:52 +02:00
Jan Dakinevich
4d8bc7334b 9pfs: fix name_to_path assertion in v9fs_complete_rename()
The third parameter of v9fs_co_name_to_path() must not contain `/'
character.

The issue is most likely related to 9p2000.u protocol only.

Signed-off-by: Jan Dakinevich <jan.dakinevich@gmail.com>
[groug, regression caused by commit f57f587857 # 2.10]
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-09-20 08:48:52 +02:00
Jan Dakinevich
6069537f43 9pfs: fix readdir() for 9p2000.u
If the client is using 9p2000.u, the following occurs:

$ cd ${virtfs_shared_dir}
$ mkdir -p a/b/c
$ ls a/b
ls: cannot access 'a/b/a': No such file or directory
ls: cannot access 'a/b/b': No such file or directory
a  b  c

instead of the expected:

$ ls a/b
c

This is a regression introduced by commit f57f5878578a;
local_name_to_path() now resolves ".." and "." in paths,
and v9fs_do_readdir_with_stat()->stat_to_v9stat() then
copies the basename of the resulting path to the response.
With the example above, this means that "." and ".." are
turned into "b" and "a" respectively...

stat_to_v9stat() currently assumes it is passed a full
canonicalized path and uses it to do two different things:
1) to pass it to v9fs_co_readlink() in case the file is a symbolic
   link
2) to set the name field of the V9fsStat structure to the basename
   part of the given path

It only has two users: v9fs_stat() and v9fs_do_readdir_with_stat().

v9fs_stat() really needs 1) and 2) to be performed since it starts
with the full canonicalized path stored in the fid. It is different
for v9fs_do_readdir_with_stat() though because the name we want to
put into the V9fsStat structure is the d_name field of the dirent
actually (ie, we want to keep the "." and ".." special names). So,
we only need 1) in this case.

This patch hence adds a basename argument to stat_to_v9stat(), to
be used to set the name field of the V9fsStat structure, and moves
the basename logic to v9fs_stat().

Signed-off-by: Jan Dakinevich <jan.dakinevich@gmail.com>
(groug, renamed old name argument to path and updated changelog)
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-09-20 08:48:51 +02:00
Greg Kurz
aa5e85a108 9pfs: local: clarify fchmodat_nofollow() implementation
Since fchmodat(2) on Linux doesn't support AT_SYMLINK_NOFOLLOW, we have to
implement it using workarounds. There are two different ways, depending on
whether the system supports O_PATH or not.

In the case O_PATH is supported, we rely on the behavhior of openat(2)
when passing O_NOFOLLOW | O_PATH and the file is a symbolic link. Even
if openat_file() already adds O_NOFOLLOW to the flags, this patch makes
it explicit that we need both creation flags to obtain the expected
behavior.

This is only cleanup, no functional change.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-09-05 17:56:58 +02:00
Philippe Mathieu-Daudé
403a905b03 9pfs: avoid sign conversion error simplifying the code
(note this is how other functions also handle the errors).

hw/9pfs/9p.c:948:18: warning: Loss of sign in implicit conversion
        offset = err;
                 ^~~

Reported-by: Clang Static Analyzer
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-09-05 14:01:16 +02:00
Cornelia Huck
5f8c92e1d5 9pfs: fix dependencies
Nothing in fsdev/ or hw/9pfs/ depends on pci; it should rather depend
on CONFIG_VIRTFS and CONFIG_VIRTIO/CONFIG_XEN only.

Acked-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-08-30 18:23:25 +02:00
Greg Kurz
4751fd5328 9pfs: local: fix fchmodat_nofollow() limitations
This function has to ensure it doesn't follow a symlink that could be used
to escape the virtfs directory. This could be easily achieved if fchmodat()
on linux honored the AT_SYMLINK_NOFOLLOW flag as described in POSIX, but
it doesn't. There was a tentative to implement a new fchmodat2() syscall
with the correct semantics:

https://patchwork.kernel.org/patch/9596301/

but it didn't gain much momentum. Also it was suggested to look at an O_PATH
based solution in the first place.

The current implementation covers most use-cases, but it notably fails if:
- the target path has access rights equal to 0000 (openat() returns EPERM),
  => once you've done chmod(0000) on a file, you can never chmod() again
- the target path is UNIX domain socket (openat() returns ENXIO)
  => bind() of UNIX domain sockets fails if the file is on 9pfs

The solution is to use O_PATH: openat() now succeeds in both cases, and we
can ensure the path isn't a symlink with fstat(). The associated entry in
"/proc/self/fd" can hence be safely passed to the regular chmod() syscall.

The previous behavior is kept for older systems that don't have O_PATH.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Zhi Yong Wu <zhiyong.wu@ucloud.cn>
Acked-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-08-10 14:36:11 +02:00
Philippe Mathieu-Daudé
87e0331c5a docs: fix broken paths to docs/devel/tracing.txt
With the move of some docs/ to docs/devel/ on ac06724a71,
no references were updated.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-07-31 13:12:53 +03:00
Alistair Francis
3dc6f86936 Convert error_report() to warn_report()
Convert all uses of error_report("warning:"... to use warn_report()
instead. This helps standardise on a single method of printing warnings
to the user.

All of the warnings were changed using these two commands:
    find ./* -type f -exec sed -i \
      's|error_report(".*warning[,:] |warn_report("|Ig' {} +

Indentation fixed up manually afterwards.

The test-qdev-global-props test case was manually updated to ensure that
this patch passes make check (as the test cases are case sensitive).

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Suggested-by: Thomas Huth <thuth@redhat.com>
Cc: Jeff Cody <jcody@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Lieven <pl@kamp.de>
Cc: Josh Durgin <jdurgin@redhat.com>
Cc: "Richard W.M. Jones" <rjones@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Greg Kurz <groug@kaod.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Peter Chubb <peter.chubb@nicta.com.au>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Alexander Graf <agraf@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Greg Kurz <groug@kaod.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed by: Peter Chubb <peter.chubb@data61.csiro.au>
Acked-by: Max Reitz <mreitz@redhat.com>
Acked-by: Marcel Apfelbaum <marcel@redhat.com>
Message-Id: <e1cfa2cd47087c248dd24caca9c33d9af0c499b0.1499866456.git.alistair.francis@xilinx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-07-13 13:49:58 +02:00
Greg Kurz
06a37db7b1 9pfs: handle transport errors in pdu_complete()
Contrary to what is written in the comment, a buggy guest can misconfigure
the transport buffers and pdu_marshal() may return an error.  If this ever
happens, it is up to the transport layer to handle the situation (9P is
transport agnostic).

This fixes Coverity issue CID1348518.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2017-06-29 15:11:51 +02:00
Stefano Stabellini
e08d1e11ed xen-9pfs: disconnect if buffers are misconfigured
Implement xen_9pfs_disconnect by unbinding the event channels. On
xen_9pfs_free, call disconnect if any event channels haven't been
disconnected.

If the frontend misconfigured the buffers set the backend to "Closing"
and disconnect it. Misconfigurations include requesting a read of more
bytes than available on the ring buffer, or claiming to be writing more
data than available on the ring buffer.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-06-29 15:11:51 +02:00
Greg Kurz
8d37de41ca virtio-9p: break device if buffers are misconfigured
The 9P protocol is transport agnostic: if the guest misconfigured the
buffers, the best we can do is to set the broken flag on the device.

Signed-off-by: Greg Kurz <groug@kaod.org>
2017-06-29 15:11:51 +02:00
Greg Kurz
a4d9985450 virtio-9p: message header is 7-byte long
The 9p spec at http://man.cat-v.org/plan_9/5/intro reads:

 "Each 9P message begins with a four-byte size field specify-
  ing the length in bytes of the complete message including
  the four bytes of the size field itself.  The next byte is
  the message type, one of the constants in the enumeration in
  the include file <fcall.h>.  The next two bytes are an iden-
  tifying tag, described below."

ie, each message starts with a 7-byte long header.

The core 9P code already assumes this pretty much everywhere. This patch
does the following:
- makes the assumption explicit in the common 9p.h header, since it isn't
  related to the transport
- open codes the header size in handle_9p_output() and hardens the sanity
  check on the space needed for the reply message

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
2017-06-29 15:11:50 +02:00
Greg Kurz
3a21fb2af0 virtio-9p: record element after sanity checks
If the guest sends a malformed request, we end up with a dangling pointer
in V9fsVirtioState. This doesn't seem to cause any bug, but let's remove
this side effect anyway.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2017-06-29 15:11:50 +02:00
Marc-André Lureau
453a1b234f 9pfs: replace g_malloc()+memcpy() with g_memdup()
I found these pattern via grepping the source tree. I don't have a
coccinelle script for it!

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-06-29 15:11:50 +02:00
Tobias Schramm
b96feb2cb9 9pfs: local: Add support for custom fmode/dmode in 9ps mapped security modes
In mapped security modes, files are created with very restrictive
permissions (600 for files and 700 for directories). This makes
file sharing between virtual machines and users on the host rather
complicated. Imagine eg. a group of users that need to access data
produced by processes on a virtual machine. Giving those users access
to the data will be difficult since the group access mode is always 0.

This patch makes the default mode for both files and directories
configurable. Existing setups that don't know about the new parameters
keep using the current secure behavior.

Signed-off-by: Tobias Schramm <tobleminer@gmail.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-06-29 15:11:50 +02:00
Bruce Rogers
790db7efdb 9pfs: local: remove: use correct path component
Commit a0e640a8 introduced a path processing error.
Pass fstatat the dirpath based path component instead
of the entire path.

Signed-off-by: Bruce Rogers <brogers@suse.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-06-29 15:11:50 +02:00
Greg Kurz
81ffbf5ab1 9pfs: local: metadata file for the VirtFS root
When using the mapped-file security, credentials are stored in a metadata
directory located in the parent directory. This is okay for all paths with
the notable exception of the root path, since we don't want and probably
can't create a metadata directory above the virtfs directory on the host.

This patch introduces a dedicated metadata file, sitting in the virtfs root
for this purpose. It relies on the fact that the "." name necessarily refers
to the virtfs root.

As for the metadata directory, we don't want the client to see this file.
The current code only cares for readdir() but there are many other places
to fix actually. The filtering logic is hence put in a separate function.

Before:

# ls -ld
drwxr-xr-x. 3 greg greg 4096 May  5 12:49 .
# chown root.root .
chown: changing ownership of '.': Is a directory
# ls -ld
drwxr-xr-x. 3 greg greg 4096 May  5 12:49 .

After:

# ls -ld
drwxr-xr-x. 3 greg greg 4096 May  5 12:49 .
# chown root.root .
# ls -ld
drwxr-xr-x. 3 root root 4096 May  5 12:50 .

and from the host:

ls -al .virtfs_metadata_root
-rwx------. 1 greg greg 26 May  5 12:50 .virtfs_metadata_root
$ cat .virtfs_metadata_root
virtfs.uid=0
virtfs.gid=0

Reported-by: Leo Gaspard <leo@gaspard.io>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Leo Gaspard <leo@gaspard.io>
[groug: work around a patchew false positive in
        local_set_mapped_file_attrat()]
2017-05-25 10:30:14 +02:00
Greg Kurz
3dbcf27334 9pfs: local: simplify file opening
The logic to open a path currently sits between local_open_nofollow() and
the relative_openat_nofollow() helper, which has no other user.

For the sake of clarity, this patch moves all the code of the helper into
its unique caller. While here we also:
- drop the code to skip leading "/" because the backend isn't supposed to
  pass anything but relative paths without consecutive slashes. The assert()
  is kept because we really don't want a buggy backend to pass an absolute
  path to openat().
- use strchrnul() to get a simpler code. This is ok since virtfs is for
  linux+glibc hosts only.
- don't dup() the initial directory and add an assert() to ensure we don't
  return the global mountfd to the caller. BTW, this would mean that the
  caller passed an empty path, which isn't supposed to happen either.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[groug: fixed typos in changelog]
2017-05-25 10:30:14 +02:00
Greg Kurz
f57f587857 9pfs: local: resolve special directories in paths
When using the mapped-file security mode, the creds of a path /foo/bar
are stored in the /foo/.virtfs_metadata/bar file. This is okay for all
paths unless they end with '.' or '..', because we cannot create the
corresponding file in the metadata directory.

This patch ensures that '.' and '..' are resolved in all paths.

The core code only passes path elements (no '/') to the backend, with
the notable exception of the '/' path, which refers to the virtfs root.
This patch preserves the current behavior of converting it to '.' so
that it can be passed to "*at()" syscalls ('/' would mean the host root).

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-05-25 10:30:14 +02:00
Greg Kurz
4fa62005d0 9pfs: check return value of v9fs_co_name_to_path()
These v9fs_co_name_to_path() call sites have always been around. I guess
no care was taken to check the return value because the name_to_path
operation could never fail at the time. This is no longer true: the
handle and synth backends can already fail this operation, and so will the
local backend soon.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-05-25 10:30:14 +02:00
Greg Kurz
24df3371d9 9pfs: assume utimensat() and futimens() are present
The utimensat() and futimens() syscalls have been around for ages (ie,
glibc 2.6 and linux 2.6.22), and the decision was already taken to
switch to utimensat() anyway when fixing CVE-2016-9602 in 2.9.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-05-25 10:30:14 +02:00
Greg Kurz
6a87e7929f 9pfs: local: fix unlink of alien files in mapped-file mode
When trying to remove a file from a directory, both created in non-mapped
mode, the file remains and EBADF is returned to the guest.

This is a regression introduced by commit "df4938a6651b 9pfs: local:
unlinkat: don't follow symlinks" when fixing CVE-2016-9602. It changed the
way we unlink the metadata file from

    ret = remove("$dir/.virtfs_metadata/$name");
    if (ret < 0 && errno != ENOENT) {
         /* Error out */
    }
    /* Ignore absence of metadata */

to

    fd = openat("$dir/.virtfs_metadata")
    unlinkat(fd, "$name")
    if (ret < 0 && errno != ENOENT) {
         /* Error out */
    }
    /* Ignore absence of metadata */

If $dir was created in non-mapped mode, openat() fails with ENOENT and
we pass -1 to unlinkat(), which fails in turn with EBADF.

We just need to check the return of openat() and ignore ENOENT, in order
to restore the behaviour we had with remove().

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[groug: rewrote the comments as suggested by Eric]
2017-05-25 10:30:13 +02:00
Greg Kurz
a17d8659c4 9pfs: drop pdu_push_and_notify()
Only pdu_complete() needs to notify the client that a request has completed.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2017-05-25 10:30:13 +02:00
Greg Kurz
506f327582 virtio-9p/xen-9p: move 9p specific bits to core 9p code
These bits aren't related to the transport so let's move them to the core
code.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2017-05-25 10:30:13 +02:00
Stefan Hajnoczi
2ccbd47c1d migration/next for 20170517
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Merge remote-tracking branch 'quintela/tags/migration/20170517' into staging

migration/next for 20170517

# gpg: Signature made Wed 17 May 2017 11:46:36 AM BST
# gpg:                using RSA key 0xF487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* quintela/tags/migration/20170517:
  migration: Move check_migratable() into qdev.c
  migration: Move postcopy stuff to postcopy-ram.c
  migration: Move page_cache.c to migration/
  migration: Create migration/blocker.h
  ram: Rename RAM_SAVE_FLAG_COMPRESS to RAM_SAVE_FLAG_ZERO
  migration: Pass Error ** argument to {save,load}_vmstate
  migration: Fix regression with compression threads

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-05-18 10:05:52 +01:00
Juan Quintela
795c40b8bd migration: Create migration/blocker.h
This allows us to remove lots of includes of migration/migration.h

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-05-17 12:04:59 +02:00
Stefano Stabellini
01cd90b641 xen: call qemu_set_cloexec instead of fcntl
Use the common utility function, which contains checks on return values
and first calls F_GETFD as recommended by POSIX.1-2001, instead of
manually calling fcntl.

CID: 1374831

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: groug@kaod.org
CC: aneesh.kumar@linux.vnet.ibm.com
CC: Eric Blake <eblake@redhat.com>
2017-05-16 11:51:25 -07:00
Stefano Stabellini
c0c24b9554 xen/9pfs: fix two resource leaks on error paths, discovered by Coverity
CID: 1374836

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: groug@kaod.org
CC: aneesh.kumar@linux.vnet.ibm.com
2017-05-16 11:50:30 -07:00
Greg Kurz
7a95434e0c 9pfs: local: forbid client access to metadata (CVE-2017-7493)
When using the mapped-file security mode, we shouldn't let the client mess
with the metadata. The current code already tries to hide the metadata dir
from the client by skipping it in local_readdir(). But the client can still
access or modify it through several other operations. This can be used to
escalate privileges in the guest.

Affected backend operations are:
- local_mknod()
- local_mkdir()
- local_open2()
- local_symlink()
- local_link()
- local_unlinkat()
- local_renameat()
- local_rename()
- local_name_to_path()

Other operations are safe because they are only passed a fid path, which
is computed internally in local_name_to_path().

This patch converts all the functions listed above to fail and return
EINVAL when being passed the name of the metadata dir. This may look
like a poor choice for errno, but there's no such thing as an illegal
path name on Linux and I could not think of anything better.

This fixes CVE-2017-7493.

Reported-by: Leo Gaspard <leo@gaspard.io>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-05-15 15:20:57 +02:00
Peter Maydell
52e94ea5de Xen 2017/04/21 + fix
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Merge remote-tracking branch 'remotes/sstabellini/tags/xen-20170421-v2-tag' into staging

Xen 2017/04/21 + fix

# gpg: Signature made Tue 25 Apr 2017 19:10:37 BST
# gpg:                using RSA key 0x894F8F4870E1AE90
# gpg: Good signature from "Stefano Stabellini <stefano.stabellini@eu.citrix.com>"
# gpg:                 aka "Stefano Stabellini <sstabellini@kernel.org>"
# Primary key fingerprint: D04E 33AB A51F 67BA 07D3  0AEA 894F 8F48 70E1 AE90

* remotes/sstabellini/tags/xen-20170421-v2-tag: (21 commits)
  move xen-mapcache.c to hw/i386/xen/
  move xen-hvm.c to hw/i386/xen/
  move xen-common.c to hw/xen/
  add xen-9p-backend to MAINTAINERS under Xen
  xen/9pfs: build and register Xen 9pfs backend
  xen/9pfs: send responses back to the frontend
  xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
  xen/9pfs: receive requests from the frontend
  xen/9pfs: connect to the frontend
  xen/9pfs: introduce Xen 9pfs backend
  9p: introduce a type for the 9p header
  xen: import ring.h from xen
  configure: use pkg-config for obtaining xen version
  xen: additionally restrict xenforeignmemory operations
  xen: use libxendevice model to restrict operations
  xen: use 5 digit xen versions
  xen: use libxendevicemodel when available
  configure: detect presence of libxendevicemodel
  xen: create wrappers for all other uses of xc_hvm_XXX() functions
  xen: rename xen_modified_memory() to xen_hvm_modified_memory()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-04-26 10:22:31 +01:00
Stefano Stabellini
e737b6d5c3 xen/9pfs: build and register Xen 9pfs backend
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-25 11:04:33 -07:00
Stefano Stabellini
4476e09e34 xen/9pfs: send responses back to the frontend
Once a request is completed, xen_9pfs_push_and_notify gets called. In
xen_9pfs_push_and_notify, update the indexes (data has already been
copied to the sg by the common code) and send a notification to the
frontend.

Schedule the bottom-half to check if we already have any other requests
pending.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-25 11:04:33 -07:00
Stefano Stabellini
40a2389207 xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
Implement xen_9pfs_init_in/out_iov_from_pdu and
xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
data on the ring.

This is safe as we only handle one request per ring at any given time.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-25 11:04:33 -07:00
Stefano Stabellini
47b70fb1e4 xen/9pfs: receive requests from the frontend
Upon receiving an event channel notification from the frontend, schedule
the bottom half. From the bottom half, read one request from the ring,
create a pdu and call pdu_submit to handle it.

For now, only handle one request per ring at a time.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-25 11:04:33 -07:00
Stefano Stabellini
f23ef34a5d xen/9pfs: connect to the frontend
Write the limits of the backend to xenstore. Connect to the frontend.
Upon connection, allocate the rings according to the protocol
specification.

Initialize a QEMUBH to schedule work upon receiving an event channel
notification from the frontend.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-25 11:04:33 -07:00
Stefano Stabellini
b37eeb0201 xen/9pfs: introduce Xen 9pfs backend
Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
Xen backend and add struct V9fsTransport to register as v9fs transport.

All functions are empty stubs for now.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-25 11:04:28 -07:00
Stefano Stabellini
c9fb47e7d0 9p: introduce a type for the 9p header
Use the new type in virtio-9p-device.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
2017-04-21 12:41:29 -07:00
Greg Kurz
9c6b899f7a 9pfs: local: set the path of the export root to "."
The local backend was recently converted to using "at*()" syscalls in order
to ensure all accesses happen below the shared directory. This requires that
we only pass relative paths, otherwise the dirfd argument to the "at*()"
syscalls is ignored and the path is treated as an absolute path in the host.
This is actually the case for paths in all fids, with the notable exception
of the root fid, whose path is "/". This causes the following backend ops to
act on the "/" directory of the host instead of the virtfs shared directory
when the export root is involved:
- lstat
- chmod
- chown
- utimensat

ie, chmod /9p_mount_point in the guest will be converted to chmod / in the
host for example. This could cause security issues with a privileged QEMU.

All "*at()" syscalls are being passed an open file descriptor. In the case
of the export root, this file descriptor points to the path in the host that
was passed to -fsdev.

The fix is thus as simple as changing the path of the export root fid to be
"." instead of "/".

This is CVE-2017-7471.

Cc: qemu-stable@nongnu.org
Reported-by: Léo Gaspard <leo@gaspard.io>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-04-18 14:01:43 +01:00
Li Qiang
4ffcdef427 9pfs: xattr: fix memory leak in v9fs_list_xattr
Free 'orig_value' in error path.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-04-10 09:38:05 +02:00
Greg Kurz
6d54af0ea9 9pfs: clear migration blocker at session reset
The migration blocker survives a device reset: if the guest mounts a 9p
share and then gets rebooted with system_reset, it will be unmigratable
until it remounts and umounts the 9p share again.

This happens because the migration blocker is supposed to be cleared when
we put the last reference on the root fid, but virtfs_reset() wrongly calls
free_fid() instead of put_fid().

This patch fixes virtfs_reset() so that it honor the way fids are supposed
to be manipulated: first get a reference and later put it back when you're
done.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Li Qiang <liqiang6-s@360.cn>
2017-04-04 18:06:01 +02:00
Greg Kurz
18adde86dd 9pfs: fix multiple flush for same request
If a client tries to flush the same outstanding request several times, only
the first flush completes. Subsequent ones keep waiting for the request
completion in v9fs_flush() and, therefore, leak a PDU. This will cause QEMU
to hang when draining active PDUs the next time the device is reset.

Let have each flush request wake up the next one if any. The last waiter
frees the cancelled PDU.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-04-04 18:06:01 +02:00
Li Qiang
d63fb193e7 9pfs: fix file descriptor leak
The v9fs_create() and v9fs_lcreate() functions are used to create a file
on the backend and to associate it to a fid. The fid shouldn't be already
in-use, otherwise both functions may silently leak a file descriptor or
allocated memory. The current code doesn't check that.

This patch ensures that the fid isn't already associated to anything
before using it.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
(reworded the changelog, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-03-27 21:13:19 +02:00
Greg Kurz
262169abe7 9pfs: proxy: assert if unmarshal fails
Replies from the virtfs proxy are made up of a fixed-size header (8 bytes)
and a payload of variable size (maximum 64kb). When receiving a reply,
the proxy backend first reads the whole header and then unmarshals it.
If the header is okay, it then does the same operation with the payload.

Since the proxy backend uses a pre-allocated buffer which has enough room
for a header and the maximum payload size, marshalling should never fail
with fixed size arguments. Any error here is likely to result from a more
serious corruption in QEMU and we'd better dump core right away.

This patch adds error checks where they are missing and converts the
associated error paths into assertions.

This should also address Coverity's complaints CID 1348519 and CID 1348520,
about not always checking the return value of proxy_unmarshal().

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-03-21 09:12:47 +01:00
Greg Kurz
d5f2af7b95 9pfs: don't try to flush self and avoid QEMU hang on reset
According to the 9P spec [*], when a client wants to cancel a pending I/O
request identified by a given tag (uint16), it must send a Tflush message
and wait for the server to respond with a Rflush message before reusing this
tag for another I/O. The server may still send a completion message for the
I/O if it wasn't actually cancelled but the Rflush message must arrive after
that.

QEMU hence waits for the flushed PDU to complete before sending the Rflush
message back to the client.

If a client sends 'Tflush tag oldtag' and tag == oldtag, QEMU will then
allocate a PDU identified by tag, find it in the PDU list and wait for
this same PDU to complete... i.e. wait for a completion that will never
happen. This causes a tag and ring slot leak in the guest, and a PDU
leak in QEMU, all of them limited by the maximal number of PDUs (128).
But, worse, this causes QEMU to hang on device reset since v9fs_reset()
wants to drain all pending I/O.

This insane behavior is likely to denote a bug in the client, and it would
deserve an Rerror message to be sent back. Unfortunately, the protocol
allows it and requires all flush requests to suceed (only a Tflush response
is expected).

The only option is to detect when we have to handle a self-referencing
flush request and report success to the client right away.

[*] http://man.cat-v.org/plan_9/5/flush

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-03-21 09:12:47 +01:00
Greg Kurz
b003fc0d8a 9pfs: fix vulnerability in openat_dir() and local_unlinkat_common()
We should pass O_NOFOLLOW otherwise openat() will follow symlinks and make
QEMU vulnerable.

While here, we also fix local_unlinkat_common() to use openat_dir() for
the same reasons (it was a leftover in the original patchset actually).

This fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-06 17:34:01 +01:00
Greg Kurz
918112c02a 9pfs: fix O_PATH build break with older glibc versions
When O_PATH is used with O_DIRECTORY, it only acts as an optimization: the
openat() syscall simply finds the name in the VFS, and doesn't trigger the
underlying filesystem.

On systems that don't define O_PATH, because they have glibc version 2.13
or older for example, we can safely omit it. We don't want to deactivate
O_PATH globally though, in case it is used without O_DIRECTORY. The is done
with a dedicated macro.

Systems without O_PATH may thus fail to resolve names that involve
unreadable directories, compared to newer systems succeeding, but such
corner case failure is our only option on those older systems to avoid
the security hole of chasing symlinks inappropriately.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
(added last paragraph to changelog as suggested by Eric Blake)
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-03-06 17:34:01 +01:00
Greg Kurz
b314f6a077 9pfs: don't use AT_EMPTY_PATH in local_set_cred_passthrough()
The name argument can never be an empty string, and dirfd always point to
the containing directory of the file name. AT_EMPTY_PATH is hence useless
here. Also it breaks build with glibc version 2.13 and older.

It is actually an oversight of a previous tentative patch to implement this
function. We can safely drop it.

Reported-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Greg Kurz <groug@kaod.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-06 17:34:01 +01:00
Greg Kurz
23da0145cc 9pfs: fail local_statfs() earlier
If we cannot open the given path, we can return right away instead of
passing -1 to fstatfs() and close(). This will make Coverity happy.

(Coverity issue CID1371729)

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel P. berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-03-06 17:34:01 +01:00
Greg Kurz
faab207f11 9pfs: fix fd leak in local_opendir()
Coverity issue CID1371731

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-03-06 17:34:01 +01:00
Greg Kurz
b7361d46e7 9pfs: fix bogus fd check in local_remove()
This was spotted by Coverity as a fd leak. This is certainly true, but also
local_remove() would always return without doing anything, unless the fd is
zero, which is very unlikely.

(Coverity issue CID1371732)

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-06 17:34:01 +01:00
Peter Maydell
7287e3556f This pull request have all the fixes for CVE-2016-9602, so that it can
be easily picked up by downstreams, as suggested by Michel Tokarev.
 -----BEGIN PGP SIGNATURE-----
 
 iEYEABECAAYFAli1TywACgkQAvw66wEB28Lq+gCeKV58yNI4imzrSdowADsO+x96
 hvcAmwaXc+3m/l/eEuCe8g2qxyiBZ6Bi
 =4/LM
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/gkurz/tags/cve-2016-9602-for-upstream' into staging

This pull request have all the fixes for CVE-2016-9602, so that it can
be easily picked up by downstreams, as suggested by Michel Tokarev.

# gpg: Signature made Tue 28 Feb 2017 10:21:32 GMT
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "[jpeg image of size 3330]"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/cve-2016-9602-for-upstream: (28 commits)
  9pfs: local: drop unused code
  9pfs: local: open2: don't follow symlinks
  9pfs: local: mkdir: don't follow symlinks
  9pfs: local: mknod: don't follow symlinks
  9pfs: local: symlink: don't follow symlinks
  9pfs: local: chown: don't follow symlinks
  9pfs: local: chmod: don't follow symlinks
  9pfs: local: link: don't follow symlinks
  9pfs: local: improve error handling in link op
  9pfs: local: rename: use renameat
  9pfs: local: renameat: don't follow symlinks
  9pfs: local: lstat: don't follow symlinks
  9pfs: local: readlink: don't follow symlinks
  9pfs: local: truncate: don't follow symlinks
  9pfs: local: statfs: don't follow symlinks
  9pfs: local: utimensat: don't follow symlinks
  9pfs: local: remove: don't follow symlinks
  9pfs: local: unlinkat: don't follow symlinks
  9pfs: local: lremovexattr: don't follow symlinks
  9pfs: local: lsetxattr: don't follow symlinks
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-03-01 13:53:20 +00:00
Greg Kurz
c23d5f1d5b 9pfs: local: drop unused code
Now that the all callbacks have been converted to use "at" syscalls, we
can drop this code.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
a565fea565 9pfs: local: open2: don't follow symlinks
The local_open2() callback is vulnerable to symlink attacks because it
calls:

(1) open() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one
(4) local_post_create_passthrough() which calls in turn lchown() and
    chmod(), both functions also following symbolic links

This patch converts local_open2() to rely on opendir_nofollow() and
mkdirat() to fix (1), as well as local_set_xattrat(),
local_set_mapped_file_attrat() and local_set_cred_passthrough() to
fix (2), (3) and (4) respectively. Since local_open2() already opens
a descriptor to the target file, local_set_cred_passthrough() is
modified to reuse it instead of opening a new one.

The mapped and mapped-file security modes are supposed to be identical,
except for the place where credentials and file modes are stored. While
here, we also make that explicit by sharing the call to openat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
3f3a16990b 9pfs: local: mkdir: don't follow symlinks
The local_mkdir() callback is vulnerable to symlink attacks because it
calls:

(1) mkdir() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one
(4) local_post_create_passthrough() which calls in turn lchown() and
    chmod(), both functions also following symbolic links

This patch converts local_mkdir() to rely on opendir_nofollow() and
mkdirat() to fix (1), as well as local_set_xattrat(),
local_set_mapped_file_attrat() and local_set_cred_passthrough() to
fix (2), (3) and (4) respectively.

The mapped and mapped-file security modes are supposed to be identical,
except for the place where credentials and file modes are stored. While
here, we also make that explicit by sharing the call to mkdirat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
d815e72190 9pfs: local: mknod: don't follow symlinks
The local_mknod() callback is vulnerable to symlink attacks because it
calls:

(1) mknod() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one
(4) local_post_create_passthrough() which calls in turn lchown() and
    chmod(), both functions also following symbolic links

This patch converts local_mknod() to rely on opendir_nofollow() and
mknodat() to fix (1), as well as local_set_xattrat() and
local_set_mapped_file_attrat() to fix (2) and (3) respectively.

A new local_set_cred_passthrough() helper based on fchownat() and
fchmodat_nofollow() is introduced as a replacement to
local_post_create_passthrough() to fix (4).

The mapped and mapped-file security modes are supposed to be identical,
except for the place where credentials and file modes are stored. While
here, we also make that explicit by sharing the call to mknodat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
38771613ea 9pfs: local: symlink: don't follow symlinks
The local_symlink() callback is vulnerable to symlink attacks because it
calls:

(1) symlink() which follows symbolic links for all path elements but the
    rightmost one
(2) open(O_NOFOLLOW) which follows symbolic links for all path elements but
    the rightmost one
(3) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(4) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one

This patch converts local_symlink() to rely on opendir_nofollow() and
symlinkat() to fix (1), openat(O_NOFOLLOW) to fix (2), as well as
local_set_xattrat() and local_set_mapped_file_attrat() to fix (3) and
(4) respectively.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
d369f20763 9pfs: local: chown: don't follow symlinks
The local_chown() callback is vulnerable to symlink attacks because it
calls:

(1) lchown() which follows symbolic links for all path elements but the
    rightmost one
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one

This patch converts local_chown() to rely on open_nofollow() and
fchownat() to fix (1), as well as local_set_xattrat() and
local_set_mapped_file_attrat() to fix (2) and (3) respectively.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
e3187a45dd 9pfs: local: chmod: don't follow symlinks
The local_chmod() callback is vulnerable to symlink attacks because it
calls:

(1) chmod() which follows symbolic links for all path elements
(2) local_set_xattr()->setxattr() which follows symbolic links for all
    path elements
(3) local_set_mapped_file_attr() which calls in turn local_fopen() and
    mkdir(), both functions following symbolic links for all path
    elements but the rightmost one

We would need fchmodat() to implement AT_SYMLINK_NOFOLLOW to fix (1). This
isn't the case on linux unfortunately: the kernel doesn't even have a flags
argument to the syscall :-\ It is impossible to fix it in userspace in
a race-free manner. This patch hence converts local_chmod() to rely on
open_nofollow() and fchmod(). This fixes the vulnerability but introduces
a limitation: the target file must readable and/or writable for the call
to openat() to succeed.

It introduces a local_set_xattrat() replacement to local_set_xattr()
based on fsetxattrat() to fix (2), and a local_set_mapped_file_attrat()
replacement to local_set_mapped_file_attr() based on local_fopenat()
and mkdirat() to fix (3). No effort is made to factor out code because
both local_set_xattr() and local_set_mapped_file_attr() will be dropped
when all users have been converted to use the "at" versions.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
ad0b46e6ac 9pfs: local: link: don't follow symlinks
The local_link() callback is vulnerable to symlink attacks because it calls:

(1) link() which follows symbolic links for all path elements but the
    rightmost one
(2) local_create_mapped_attr_dir()->mkdir() which follows symbolic links
    for all path elements but the rightmost one

This patch converts local_link() to rely on opendir_nofollow() and linkat()
to fix (1), mkdirat() to fix (2).

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
6dd4b1f1d0 9pfs: local: improve error handling in link op
When using the mapped-file security model, we also have to create a link
for the metadata file if it exists. In case of failure, we should rollback.

That's what this patch does.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
d2767edec5 9pfs: local: rename: use renameat
The local_rename() callback is vulnerable to symlink attacks because it
uses rename() which follows symbolic links in all path elements but the
rightmost one.

This patch simply transforms local_rename() into a wrapper around
local_renameat() which is symlink-attack safe.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
99f2cf4b2d 9pfs: local: renameat: don't follow symlinks
The local_renameat() callback is currently a wrapper around local_rename()
which is vulnerable to symlink attacks.

This patch rewrites local_renameat() to have its own implementation, based
on local_opendir_nofollow() and renameat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
f9aef99b3e 9pfs: local: lstat: don't follow symlinks
The local_lstat() callback is vulnerable to symlink attacks because it
calls:

(1) lstat() which follows symbolic links in all path elements but the
    rightmost one
(2) getxattr() which follows symbolic links in all path elements
(3) local_mapped_file_attr()->local_fopen()->openat(O_NOFOLLOW) which
    follows symbolic links in all path elements but the rightmost
    one

This patch converts local_lstat() to rely on opendir_nofollow() and
fstatat(AT_SYMLINK_NOFOLLOW) to fix (1), fgetxattrat_nofollow() to
fix (2).

A new local_fopenat() helper is introduced as a replacement to
local_fopen() to fix (3). No effort is made to factor out code
because local_fopen() will be dropped when all users have been
converted to call local_fopenat().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
bec1e9546e 9pfs: local: readlink: don't follow symlinks
The local_readlink() callback is vulnerable to symlink attacks because it
calls:

(1) open(O_NOFOLLOW) which follows symbolic links for all path elements but
    the rightmost one
(2) readlink() which follows symbolic links for all path elements but the
    rightmost one

This patch converts local_readlink() to rely on open_nofollow() to fix (1)
and opendir_nofollow(), readlinkat() to fix (2).

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
ac125d993b 9pfs: local: truncate: don't follow symlinks
The local_truncate() callback is vulnerable to symlink attacks because
it calls truncate() which follows symbolic links in all path elements.

This patch converts local_truncate() to rely on open_nofollow() and
ftruncate() instead.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
31e51d1c15 9pfs: local: statfs: don't follow symlinks
The local_statfs() callback is vulnerable to symlink attacks because it
calls statfs() which follows symbolic links in all path elements.

This patch converts local_statfs() to rely on open_nofollow() and fstatfs()
instead.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
a33eda0dd9 9pfs: local: utimensat: don't follow symlinks
The local_utimensat() callback is vulnerable to symlink attacks because it
calls qemu_utimens()->utimensat(AT_SYMLINK_NOFOLLOW) which follows symbolic
links in all path elements but the rightmost one or qemu_utimens()->utimes()
which follows symbolic links for all path elements.

This patch converts local_utimensat() to rely on opendir_nofollow() and
utimensat(AT_SYMLINK_NOFOLLOW) directly instead of using qemu_utimens().
It is hence assumed that the OS supports utimensat(), i.e. has glibc 2.6
or higher and linux 2.6.22 or higher, which seems reasonable nowadays.

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
a0e640a872 9pfs: local: remove: don't follow symlinks
The local_remove() callback is vulnerable to symlink attacks because it
calls:

(1) lstat() which follows symbolic links in all path elements but the
    rightmost one
(2) remove() which follows symbolic links in all path elements but the
    rightmost one

This patch converts local_remove() to rely on opendir_nofollow(),
fstatat(AT_SYMLINK_NOFOLLOW) to fix (1) and unlinkat() to fix (2).

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
df4938a665 9pfs: local: unlinkat: don't follow symlinks
The local_unlinkat() callback is vulnerable to symlink attacks because it
calls remove() which follows symbolic links in all path elements but the
rightmost one.

This patch converts local_unlinkat() to rely on opendir_nofollow() and
unlinkat() instead.

Most of the code is moved to a separate local_unlinkat_common() helper
which will be reused in a subsequent patch to fix the same issue in
local_remove().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
72f0d0bf51 9pfs: local: lremovexattr: don't follow symlinks
The local_lremovexattr() callback is vulnerable to symlink attacks because
it calls lremovexattr() which follows symbolic links in all path elements
but the rightmost one.

This patch introduces a helper to emulate the non-existing fremovexattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to lremovexattr().

local_lremovexattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
3e36aba757 9pfs: local: lsetxattr: don't follow symlinks
The local_lsetxattr() callback is vulnerable to symlink attacks because
it calls lsetxattr() which follows symbolic links in all path elements but
the rightmost one.

This patch introduces a helper to emulate the non-existing fsetxattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to lsetxattr().

local_lsetxattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
5507904e36 9pfs: local: llistxattr: don't follow symlinks
The local_llistxattr() callback is vulnerable to symlink attacks because
it calls llistxattr() which follows symbolic links in all path elements but
the rightmost one.

This patch introduces a helper to emulate the non-existing flistxattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to llistxattr().

local_llistxattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
56ad3e54da 9pfs: local: lgetxattr: don't follow symlinks
The local_lgetxattr() callback is vulnerable to symlink attacks because
it calls lgetxattr() which follows symbolic links in all path elements but
the rightmost one.

This patch introduces a helper to emulate the non-existing fgetxattrat()
function: it is implemented with /proc/self/fd which provides a trusted
path that can be safely passed to lgetxattr().

local_lgetxattr() is converted to use this helper and opendir_nofollow().

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
996a0d76d7 9pfs: local: open/opendir: don't follow symlinks
The local_open() and local_opendir() callbacks are vulnerable to symlink
attacks because they call:

(1) open(O_NOFOLLOW) which follows symbolic links in all path elements but
    the rightmost one
(2) opendir() which follows symbolic links in all path elements

This patch converts both callbacks to use new helpers based on
openat_nofollow() to only open files and directories if they are
below the virtfs shared folder

This partly fixes CVE-2016-9602.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
0e35a37829 9pfs: local: keep a file descriptor on the shared folder
This patch opens the shared folder and caches the file descriptor, so that
it can be used to do symlink-safe path walk.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:15 +01:00
Greg Kurz
6482a96163 9pfs: introduce relative_openat_nofollow() helper
When using the passthrough security mode, symbolic links created by the
guest are actual symbolic links on the host file system.

Since the resolution of symbolic links during path walk is supposed to
occur on the client side. The server should hence never receive any path
pointing to an actual symbolic link. This isn't guaranteed by the protocol
though, and malicious code in the guest can trick the server to issue
various syscalls on paths whose one or more elements are symbolic links.
In the case of the "local" backend using the "passthrough" or "none"
security modes, the guest can directly create symbolic links to arbitrary
locations on the host (as per spec). The "mapped-xattr" and "mapped-file"
security modes are also affected to a lesser extent as they require some
help from an external entity to create actual symbolic links on the host,
i.e. another guest using "passthrough" mode for example.

The current code hence relies on O_NOFOLLOW and "l*()" variants of system
calls. Unfortunately, this only applies to the rightmost path component.
A guest could maliciously replace any component in a trusted path with a
symbolic link. This could allow any guest to escape a virtfs shared folder.

This patch introduces a variant of the openat() syscall that successively
opens each path element with O_NOFOLLOW. When passing a file descriptor
pointing to a trusted directory, one is guaranteed to be returned a
file descriptor pointing to a path which is beneath the trusted directory.
This will be used by subsequent patches to implement symlink-safe path walk
for any access to the backend.

Symbolic links aren't the only threats actually: a malicious guest could
change a path element to point to other types of file with undesirable
effects:
- a named pipe or any other thing that would cause openat() to block
- a terminal device which would become QEMU's controlling terminal

These issues can be addressed with O_NONBLOCK and O_NOCTTY.

Two helpers are introduced: one to open intermediate path elements and one
to open the rightmost path element.

Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
(renamed openat_nofollow() to relative_openat_nofollow(),
 assert path is relative and doesn't contain '//',
 fixed side-effect in assert, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-02-28 11:21:15 +01:00
Greg Kurz
21328e1e57 9pfs: remove side-effects in local_open() and local_opendir()
If these functions fail, they should not change *fs. Let's use local
variables to fix this.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:14 +01:00
Greg Kurz
00c90bd1c2 9pfs: remove side-effects in local_init()
If this function fails, it should not modify *ctx.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:14 +01:00
Greg Kurz
56fc494bdc 9pfs: local: move xattr security ops to 9p-xattr.c
These functions are always called indirectly. It really doesn't make sense
for them to sit in a header file.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-28 11:21:14 +01:00
Pradeep Jagadeesh
b8bbdb886e fsdev: add IO throttle support to fsdev devices
This patchset adds the throttle support for the 9p-local driver.
For now this functionality can be enabled only through qemu cli options.
QMP interface and support to other drivers need further extensions.
To make it simple for other 9p drivers, the throttle code has been put in
separate files.

Signed-off-by: Pradeep Jagadeesh <pradeep.jagadeesh@huawei.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
(pass extra NULL CoMutex * argument to qemu_co_queue_wait(),
 added options to qemu-options.hx, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-02-28 10:31:46 +01:00
Paolo Bonzini
4bae2b397f 9pfs: fix v9fs_lock error case
In this case, we are marshaling an error status instead of the errno value.
Reorganize the out and out_nofid labels to look like all the other cases.
Coverity reports this because the "err = -ENOENT" and "err = -EINVAL"
assignments above are dead, overwritten by the call to pdu_marshal.

(Coverity issues CID1348512 and CID1348513)

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(also open-coded the success path since locking is a nop for us, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-02-28 10:31:46 +01:00
Paolo Bonzini
1ace7ceac5 coroutine-lock: add mutex argument to CoQueue APIs
All that CoQueue needs in order to become thread-safe is help
from an external mutex.  Add this to the API.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-6-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Peter Maydell
c7f1cf01b8 This pull request fixes a 2.9 regression and a long standing bug that can
cause 9p clients to hang. Other patches are minor enhancements.
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Merge remote-tracking branch 'remotes/gkurz/tags/for-upstream' into staging

This pull request fixes a 2.9 regression and a long standing bug that can
cause 9p clients to hang. Other patches are minor enhancements.

# gpg: Signature made Wed 25 Jan 2017 10:12:27 GMT
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@fr.ibm.com>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "Gregory Kurz (Cimai Technology) <gkurz@cimai.com>"
# gpg:                 aka "Gregory Kurz (Meiosys Technology) <gkurz@meiosys.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/for-upstream:
  9pfs: fix offset error in v9fs_xattr_read()
  9pfs: local: trivial cosmetic fix in pwritev op
  9pfs: fix off-by-one error in PDU free list
  tests: virtio-9p: improve error reporting
  9pfs: add missing coroutine_fn annotations

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-01-25 17:54:14 +00:00
Greg Kurz
fa0eb5c512 9pfs: fix offset error in v9fs_xattr_read()
The current code tries to copy `read_count' bytes starting at offset
`offset' from a `read_count`-sized iovec. This causes v9fs_pack() to
fail with ENOBUFS.

Since the PDU iovec is already partially filled with `offset' bytes,
let's skip them when creating `qiov_full' and have v9fs_pack() to
copy the whole of it. Moreover, this is consistent with the other
places where v9fs_init_qiov_from_pdu() is called.

This fixes commit "bcb8998fac16 9pfs: call v9fs_init_qiov_from_pdu
before v9fs_pack".

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2017-01-25 09:34:35 +01:00
Greg Kurz
6fe76acc2d 9pfs: local: trivial cosmetic fix in pwritev op
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-25 09:34:35 +01:00
Greg Kurz
0d78289c3d 9pfs: fix off-by-one error in PDU free list
The server can handle MAX_REQ - 1 PDUs at a time and the virtio-9p
device has a MAX_REQ sized virtqueue. If the client manages to fill
up the virtqueue, pdu_alloc() will fail and the request won't be
processed without any notice to the client (it actually causes the
linux 9p client to hang).

This has been there since the beginning (commit 9f10751365 "virtio-9p:
Add a virtio 9p device to qemu"), but it needs an agressive workload to
run in the guest to show up.

We actually allocate MAX_REQ PDUs and I see no reason not to link them
all into the free list, so let's fix the init loop.

Reported-by: Tuomas Tynkkynen <tuomas@tuxera.com>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-25 09:34:35 +01:00
Greg Kurz
a1bf8b7414 9pfs: add missing coroutine_fn annotations
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-25 09:34:35 +01:00
Ashijeet Acharya
fe44dc9180 migration: disallow migrate_add_blocker during migration
If a migration is already in progress and somebody attempts
to add a migration blocker, this should rightly fail.

Add an errp parameter and a retcode return value to migrate_add_blocker.

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1484566314-3987-5-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Merged with recent 'Allow invtsc migration' change
2017-01-24 18:00:30 +00:00
Greg Kurz
baecbde6d7 9pfs: fix P9_NOTAG and P9_NOFID macros
The u16 and u32 types don't exist in QEMU common headers. It never broke
build because these two macros aren't use by the current code, but this
is about to change with the future addition of functional tests for 9P.

Also, these should have enclosing parenthesis to be usable in any
syntactical situation.

As suggested by Eric Blake, let's use UINT16_MAX and UINT32_MAX to address
both issues.

Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-03 17:28:44 +01:00
Greg Kurz
f2b58c4375 9pfs: fix crash when fsdev is missing
If the user passes -device virtio-9p without the corresponding -fsdev, QEMU
dereferences a NULL pointer and crashes.

This is a 2.8 regression introduced by commit 702dbcc274.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
2017-01-03 17:28:44 +01:00
Stefano Stabellini
88da0b0301 9pfs: introduce init_out/in_iov_from_pdu
Not all 9pfs transports share memory between request and response. For
those who don't, it is necessary to know how much memory is required in
the response.

Split the existing init_iov_from_pdu function in two:
init_out_iov_from_pdu (for writes) and init_in_iov_from_pdu (for reads).
init_in_iov_from_pdu takes an additional size parameter to specify the
memory required for the response message.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-03 17:28:44 +01:00
Stefano Stabellini
bcb8998fac 9pfs: call v9fs_init_qiov_from_pdu before v9fs_pack
v9fs_xattr_read should not access VirtQueueElement elems directly.
Move v9fs_init_qiov_from_pdu up in the file and call
v9fs_init_qiov_from_pdu before v9fs_pack. Use v9fs_pack on the new
iovec.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-03 17:28:44 +01:00
Stefano Stabellini
ea83441cc4 9pfs: introduce transport specific callbacks
Don't call virtio functions from 9pfs generic code, use generic function
callbacks instead.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-03 17:28:44 +01:00
Stefano Stabellini
583f21f8b9 9pfs: move pdus to V9fsState
pdus are initialized and used in 9pfs common code. Move the array from
V9fsVirtioState to V9fsState.

Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2017-01-03 17:28:44 +01:00
Li Qiang
898ae90a44 9pfs: add cleanup operation for proxy backend driver
In the init operation of proxy backend dirver, it allocates a
V9fsProxy struct and some other resources. We should free these
resources when the 9pfs device is unrealized. This is what this
patch does.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-23 13:53:34 +01:00
Li Qiang
971f406b77 9pfs: add cleanup operation for handle backend driver
In the init operation of handle backend dirver, it allocates a
handle_data struct and opens a mount file. We should free these
resources when the 9pfs device is unrealized. This is what this
patch does.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-23 13:53:34 +01:00
Li Qiang
702dbcc274 9pfs: add cleanup operation in FileOperations
Currently, the backend of VirtFS doesn't have a cleanup
function. This will lead resource leak issues if the backed
driver allocates resources. This patch addresses this issue.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-23 13:53:34 +01:00
Li Qiang
4774718e5c 9pfs: adjust the order of resource cleanup in device unrealize
Unrealize should undo things that were set during realize in
reverse order. So should do in the error path in realize.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-23 13:53:34 +01:00
Greg Kurz
79decce35b 9pfs: drop excessive error message from virtfs_reset()
The virtfs_reset() function is called either when the virtio-9p device
gets reset, or when the client starts a new 9P session. In both cases,
if it finds fids from a previous session, the following is printed in
the monitor:

9pfs:virtfs_reset: One or more uncluncked fids found during reset

For example, if a linux guest with a mounted 9P share is reset from the
monitor with system_reset, the message will be printed. This is excessive
since these fids are now clunked and the state is clean.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-11-01 12:03:03 +01:00
Greg Kurz
49dd946bb5 9pfs: don't BUG_ON() if fid is already opened
A buggy or malicious guest could pass the id of an already opened fid and
cause QEMU to abort. Let's return EINVAL to the guest instead.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-11-01 12:03:02 +01:00
Greg Kurz
dd654e0365 9pfs: xattrcreate requires non-opened fids
The xattrcreate operation only makes sense on a freshly cloned fid
actually, since any open state would be leaked because of the fid_type
change. This is indeed what the linux kernel client does:

	fid = clone_fid(fid);
	[...]
	retval = p9_client_xattrcreate(fid, name, value_len, flags);

This patch also reverts commit ff55e94d23 since we are sure that a fid
with type P9_FID_NONE doesn't have a previously allocated xattr.

Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-01 12:03:02 +01:00
Greg Kurz
3b79ef2cf4 9pfs: limit xattr size in xattrcreate
We shouldn't allow guests to create extended attribute with arbitrary sizes.
On linux hosts, the limit is XATTR_SIZE_MAX. Let's use it.

Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-01 12:03:02 +01:00
Li Qiang
7e55d65c56 9pfs: fix integer overflow issue in xattr read/write
The v9fs_xattr_read() and v9fs_xattr_write() are passed a guest
originated offset: they must ensure this offset does not go beyond
the size of the extended attribute that was set in v9fs_xattrcreate().
Unfortunately, the current code implement these checks with unsafe
calculations on 32 and 64 bit values, which may allow a malicious
guest to cause OOB access anyway.

Fix this by comparing the offset and the xattr size, which are
both uint64_t, before trying to compute the effective number of bytes
to read or write.

Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-By: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-01 12:03:01 +01:00
Li Qiang
8495f9ad26 9pfs: convert 'len/copied_len' field in V9fsXattr to the type of uint64_t
The 'len' in V9fsXattr comes from the 'size' argument in setxattr()
function in guest. The setxattr() function's declaration is this:

int setxattr(const char *path, const char *name,
             const void *value, size_t size, int flags);

and 'size' is treated as u64 in linux kernel client code:

int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
                          u64 attr_size, int flags)

So the 'len' should have an type of 'uint64_t'.
The 'copied_len' in V9fsXattr is used to account for copied bytes, it
should also have an type of 'uint64_t'.

Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-01 12:03:01 +01:00
Li Qiang
dd28fbbc2e 9pfs: add xattrwalk_fid field in V9fsXattr struct
Currently, 9pfs sets the 'copied_len' field in V9fsXattr
to -1 to tag xattr walk fid. As the 'copied_len' is also
used to account for copied bytes, this may make confusion. This patch
add a bool 'xattrwalk_fid' to tag the xattr walk fid.

Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-11-01 12:00:40 +01:00
Li Qiang
fdfcc9aeea 9pfs: fix memory leak in v9fs_write
If an error occurs when marshalling the transfer length to the guest, the
v9fs_write() function doesn't free an IO vector, thus leading to a memory
leak. This patch fixes the issue.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
[groug, rephrased the changelog]
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Li Qiang
4c1586787f 9pfs: fix memory leak in v9fs_link
The v9fs_link() function keeps a reference on the source fid object. This
causes a memory leak since the reference never goes down to 0. This patch
fixes the issue.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
[groug, rephrased the changelog]
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Li Qiang
ff55e94d23 9pfs: fix memory leak in v9fs_xattrcreate
The 'fs.xattr.value' field in V9fsFidState object doesn't consider the
situation that this field has been allocated previously. Every time, it
will be allocated directly. This leads to a host memory leak issue if
the client sends another Txattrcreate message with the same fid number
before the fid from the previous time got clunked.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
[groug, updated the changelog to indicate how the leak can occur]
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Li Qiang
eb68760285 9pfs: fix information leak in xattr read
9pfs uses g_malloc() to allocate the xattr memory space, if the guest
reads this memory before writing to it, this will leak host heap memory
to the guest. This patch avoid this.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Greg Kurz
0e44a0fd3f virtio-9p: add reset handler
Virtio devices should implement the VirtIODevice->reset() function to
perform necessary cleanup actions and to bring the device to a quiescent
state.

In the case of the virtio-9p device, this means:
- emptying the list of active PDUs (i.e. draining all in-flight I/O)
- freeing all fids (i.e. close open file descriptors and free memory)

That's what this patch does.

The reset handler first waits for all active PDUs to complete. Since
completion happens in the QEMU global aio context, we just have to
loop around aio_poll() until the active list is empty.

The freeing part involves some actions to be performed on the backend,
like closing file descriptors or flushing extended attributes to the
underlying filesystem. The virtfs_reset() function already does the
job: it calls free_fid() for all open fids not involved in an ongoing
I/O operation. We are sure this is the case since we have drained
the PDU active list.

The current code implements all backend accesses with coroutines, but we
want to stay synchronous on the reset path. We can either change the
current code to be able to run when not in coroutine context, or create
a coroutine context and wait for virtfs_reset() to complete. This patch
goes for the latter because it results in simpler code.

Note that we also need to create a dummy PDU because it is also an API
to pass the FsContext pointer to all backend callbacks.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-17 14:13:58 +02:00
Greg Kurz
f74e27bf0f 9pfs: only free completed request if not flushed
If a PDU has a flush request pending, the current code calls pdu_free()
twice:

1) pdu_complete()->pdu_free() with pdu->cancelled set, which does nothing

2) v9fs_flush()->pdu_free() with pdu->cancelled cleared, which moves the
   PDU back to the free list.

This works but it complexifies the logic of pdu_free().

With this patch, pdu_complete() only calls pdu_free() if no flush request
is pending, i.e. qemu_co_queue_next() returns false.

Since pdu_free() is now supposed to be called with pdu->cancelled cleared,
the check in pdu_free() is dropped and replaced by an assertion.

Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Greg Kurz
6868a420c5 9pfs: drop useless check in pdu_free()
Out of the three users of pdu_free(), none ever passes a NULL pointer to
this function.

Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Greg Kurz
8440e22ec1 9pfs: use coroutine_fn annotation in hw/9pfs/9p.[ch]
All these functions either call the v9fs_co_* functions which have the
coroutine_fn annotation, or pdu_complete() which calls qemu_co_queue_next().

Let's mark them to make it obvious they execute in coroutine context.

Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Greg Kurz
5bdade6621 9pfs: use coroutine_fn annotation in hw/9pfs/co*.[ch]
All these functions use the v9fs_co_run_in_worker() macro, and thus always
call qemu_coroutine_self() and qemu_coroutine_yield().

Let's mark them to make it obvious they execute in coroutine context.

Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Greg Kurz
bc70a5925f 9pfs: fsdev: drop useless extern annotation for functions
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Li Qiang
e95c9a493a 9pfs: fix potential host memory leak in v9fs_read
In 9pfs read dispatch function, it doesn't free two QEMUIOVector
object thus causing potential memory leak. This patch avoid this.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Li Qiang
ba42ebb863 9pfs: allocate space for guest originated empty strings
If a guest sends an empty string paramater to any 9P operation, the current
code unmarshals it into a V9fsString equal to { .size = 0, .data = NULL }.

This is unfortunate because it can cause NULL pointer dereference to happen
at various locations in the 9pfs code. And we don't want to check str->data
everywhere we pass it to strcmp() or any other function which expects a
dereferenceable pointer.

This patch enforces the allocation of genuine C empty strings instead, so
callers don't have to bother.

Out of all v9fs_iov_vunmarshal() users, only v9fs_xattrwalk() checks if
the returned string is empty. It now uses v9fs_string_size() since
name.data cannot be NULL anymore.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
[groug, rewritten title and changelog,
 fix empty string check in v9fs_xattrwalk()]
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-10-17 14:13:58 +02:00
Halil Pasic
5705653ff8 virtio: cleanup VMSTATE_VIRTIO_DEVICE
Now all the usages of the old version of VMSTATE_VIRTIO_DEVICE are gone,
so we can get rid of the conditionals, and the old macro.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 02:21:43 +03:00
Halil Pasic
dcaf8dda4b virtio-9p: convert VMSTATE_VIRTIO_DEVICE
Use the new VMSTATE_VIRTIO_DEVICE macro.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 02:21:42 +03:00
Greg Kurz
d3d74d6fe0 virtio-9p: handle handle_9p_output() error
A broken guest may send a request without providing buffers for the reply
or for the request itself, and virtqueue_pop() will return an element with
either in_num == 0 or out_num == 0.

All 9P requests are expected to start with the following 7-byte header:

            uint32_t size_le;
            uint8_t id;
            uint16_t tag_le;

If iov_to_buf() fails to return these 7 bytes, then something is wrong in
the guest.

In both cases, it is wrong to crash QEMU, since the root cause lies in the
guest.

This patch hence does the following:
- keep the check of in_num since pdu_complete() assumes it has enough
  space to store the reply and we will send something broken to the guest
- let iov_to_buf() handle out_num == 0, since it will return 0 just like
  if the guest had provided an zero-sized buffer.
- call virtio_error() to inform the guest that the device is now broken,
  instead of aborting
- detach the request from the virtqueue and free it

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:16:59 +03:00
Greg Kurz
e8582891cb virtio-9p: add parentheses to sizeof operator
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-10 01:16:58 +03:00
Greg Kurz
13fd08e631 9pfs: fix potential segfault during walk
If the call to fid_to_qid() returns an error, we will call v9fs_path_free()
on uninitialized paths.

It is a regression introduced by the following commit:

56f101ecce 9pfs: handle walk of ".." in the root directory

Let's fix this by initializing dpath and path before calling fid_to_qid().

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
[groug: updated the changelog to indicate this is regression and to provide
        the offending commit SHA1]
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-09-19 11:39:48 +02:00
Greg Kurz
e3e83f2e21 9pfs: introduce v9fs_path_sprintf() helper
This helper is similar to v9fs_string_sprintf(), but it includes the
terminating NUL character in the size field.

This is to avoid doing v9fs_string_sprintf((V9fsString *) &path) and
then bumping the size.

Affected users are changed to use this new helper.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2016-09-16 08:56:15 +02:00
Greg Kurz
abdf008640 9pfs: drop useless v9fs_string_null() function
The v9fs_string_null() function just calls v9fs_string_free(). Also it
only has 4 users, whereas v9fs_string_free() has 87.

This patch converts users to call directly v9fs_string_free() and drops
the useless function.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2016-09-16 08:56:15 +02:00
Greg Kurz
da4bc86c54 9pfs: drop duplicate line in proxy backend
This double free did not cause harm because v9fs_string_free() sets
str->data to NULL and g_free(NULL) is valid.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2016-09-16 08:56:14 +02:00
Greg Kurz
799fe087e4 9pfs: drop unused fmt strings in the proxy backend
The v9fs_request() function doesn't use its fmt argument: it passes literal
format strings to proxy_marshal() for all commands.

This patch simply drops the unused fmt argument and updates all callers
accordingly.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2016-09-16 08:56:14 +02:00
Greg Kurz
56f101ecce 9pfs: handle walk of ".." in the root directory
The 9P spec at http://man.cat-v.org/plan_9/5/intro says:

All directories must support walks to the directory .. (dot-dot) meaning
parent directory, although by convention directories contain no explicit
entry for .. or . (dot).  The parent of the root directory of a server's
tree is itself.

This means that a client cannot walk further than the root directory
exported by the server. In other words, if the client wants to walk
"/.." or "/foo/../..", the server should answer like the request was
to walk "/".

This patch just does that:
- we cache the QID of the root directory at attach time
- during the walk we compare the QID of each path component with the root
  QID to detect if we're in a "/.." situation
- if so, we skip the current component and go to the next one

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-08-30 19:23:00 +01:00
Greg Kurz
805b5d98c6 9pfs: forbid . and .. in file names
According to the 9P spec http://man.cat-v.org/plan_9/5/open about the
create request:

The names . and .. are special; it is illegal to create files with these
names.

This patch causes the create and lcreate requests to fail with EINVAL if
the file name is either "." or "..".

Even if it isn't explicitly written in the spec, this patch extends the
checking to all requests that may cause a directory entry to be created:

    - mknod
    - rename
    - renameat
    - mkdir
    - link
    - symlink

The unlinkat request also gets patched for consistency (even if
rmdir("foo/..") is expected to fail according to POSIX.1-2001).

The various error values come from the linux manual pages.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-08-30 19:21:56 +01:00
Greg Kurz
fff39a7ad0 9pfs: forbid illegal path names
Empty path components don't make sense for most commands and may cause
undefined behavior, depending on the backend.

Also, the walk request described in the 9P spec [1] clearly shows that
the client is supposed to send individual path components: the official
linux client never sends portions of path containing the / character for
example.

Moreover, the 9P spec [2] also states that a system can decide to restrict
the set of supported characters used in path components, with an explicit
mention "to remove slashes from name components".

This patch introduces a new name_is_illegal() helper that checks the
names sent by the client are not empty and don't contain unwanted chars.
Since 9pfs is only supported on linux hosts, only the / character is
checked at the moment. When support for other hosts (AKA. win32) is added,
other chars may need to be blacklisted as well.

If a client sends an illegal path component, the request will fail and
ENOENT is returned to the client.

[1] http://man.cat-v.org/plan_9/5/walk
[2] http://man.cat-v.org/plan_9/5/intro

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-08-30 19:21:39 +01:00
Laurent Vivier
e723b87103 trace-events: fix first line comment in trace-events
Documentation is docs/tracing.txt instead of docs/trace-events.txt.

find . -name trace-events -exec \
     sed -i "s?See docs/trace-events.txt for syntax documentation.?See docs/tracing.txt for syntax documentation.?" \
     {} \;

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-id: 1470669081-17860-1-git-send-email-lvivier@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-08-12 10:36:01 +01:00
Dr. David Alan Gilbert
18e0e5b240 9pfs: Wrap in vmstate
Forcibly convert it to a vmstate wrapper;  proper conversion
comes later.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21 20:44:20 +03:00
Paolo Bonzini
0b8b8753e4 coroutine: move entry argument to qemu_coroutine_create
In practice the entry argument is always known at creation time, and
it is confusing that sometimes qemu_coroutine_enter is used with a
non-NULL argument to re-enter a coroutine (this happens in
block/sheepdog.c and tests/test-coroutine.c).  So pass the opaque value
at creation time, for consistency with e.g. aio_bh_new.

Mostly done with the following semantic patch:

@ entry1 @
expression entry, arg, co;
@@
- co = qemu_coroutine_create(entry);
+ co = qemu_coroutine_create(entry, arg);
  ...
- qemu_coroutine_enter(co, arg);
+ qemu_coroutine_enter(co);

@ entry2 @
expression entry, arg;
identifier co;
@@
- Coroutine *co = qemu_coroutine_create(entry);
+ Coroutine *co = qemu_coroutine_create(entry, arg);
  ...
- qemu_coroutine_enter(co, arg);
+ qemu_coroutine_enter(co);

@ entry3 @
expression entry, arg;
@@
- qemu_coroutine_enter(qemu_coroutine_create(entry), arg);
+ qemu_coroutine_enter(qemu_coroutine_create(entry, arg));

@ reentry @
expression co;
@@
- qemu_coroutine_enter(co, NULL);
+ qemu_coroutine_enter(co);

except for the aforementioned few places where the semantic patch
stumbled (as expected) and for test_co_queue, which would otherwise
produce an uninitialized variable warning.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-13 13:26:02 +02:00
Markus Armbruster
2a6a4076e1 Clean up ill-advised or unusual header guards
Cleaned up with scripts/clean-header-guards.pl.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-12 16:20:46 +02:00
Markus Armbruster
121d07125b Clean up header guards that don't match their file name
Header guard symbols should match their file name to make guard
collisions less likely.  Offenders found with
scripts/clean-header-guards.pl -vn.

Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-12 16:19:16 +02:00
Greg Kurz
b05528b533 9p: synth: drop v9fs_ prefix
To have shorter lines and be consistent with other fs devices.

Acked-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
2016-07-01 14:38:54 +02:00
Daniel P. Berrange
d018a2e931 trace: split out trace events for hw/9pfs/ directory
Move all trace-events for files in the hw/9pfs/ directory to
their own file.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1466066426-16657-26-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-20 17:22:16 +01:00
Peter Maydell
030c98aff1 all: Remove unnecessary glib.h includes
Remove glib.h includes, as it is provided by osdep.h.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-06-07 18:19:24 +03:00
Greg Kurz
635324e83e 9p: switch back to readdir()
This patch changes the 9p code to use readdir() again instead of
readdir_r(), which is deprecated in glibc 2.24.

All the locking was put in place by a previous patch.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
7cde47d4a8 9p: add locking to V9fsDir
If several threads concurrently call readdir() with the same directory
stream pointer, it is possible that they all get a pointer to the same
dirent structure, whose content is overwritten each time readdir() is
called.

We must thus serialize accesses to the dirent structure.

This may be achieved with a mutex like below:

lock_mutex();

readdir();

// work with the dirent

unlock_mutex();

This patch adds all the locking, to prepare the switch to readdir().

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
f314ea4e30 9p: introduce the V9fsDir type
If we are to switch back to readdir(), we need a more complex type than
DIR * to be able to serialize concurrent accesses to the directory stream.

This patch introduces a placeholder type and fixes all users.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
8762a46d36 9p: drop useless out: label
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
beff62e683 9p: drop useless inclusion of hw/i386/pc.h
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
af8b38b0d1 9p/fsdev: remove obsolete references to virtio
Most of the 9p code is now virtio agnostic. This patch does a final cleanup:
- drop references to Virtio from the header comments
- fix includes

Also drop a couple of leading empty lines while here.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
aae91ad9ae 9p: some more cleanup in #include directives
The "9p-attr.h" header isn't needed by 9p synth and virtio 9p.

While here, also drop last references to virtio from 9p synth since it is
now transport agnostic code.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-06-06 11:52:34 +02:00
Greg Kurz
d506dc87b9 9p: drop unused declaration from coth.h
Commit "ebac1202c95a virtio-9p: use QEMU thread pool" dropped function
v9fs_init_worker_threads.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-05-18 15:04:27 +03:00
Veronia Bahaa
f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell
30456d5ba3 all: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Paolo Bonzini
51b19ebe43 virtio: move allocation to virtqueue_pop/vring_pop
The return code of virtqueue_pop/vring_pop is unused except to check for
errors or 0.  We can thus easily move allocation inside the functions
and just return a pointer to the VirtQueueElement.

The advantage is that we will be able to allocate only the space that
is needed for the actual size of the s/g list instead of the full
VIRTQUEUE_MAX_SIZE items.  Currently VirtQueueElement takes about 48K
of memory, and this kind of allocation puts a lot of stress on malloc.
By cutting the size by two or three orders of magnitude, malloc can
use much more efficient algorithms.

The patch is pretty large, but changes to each device are testable
more or less independently.  Splitting it would mostly add churn.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-02-06 20:39:07 +02:00
Peter Maydell
fbc0412709 9pfs: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-18-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Peter Maydell
9b8bfe21be virtio: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-15-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Greg Kurz
63325b181f 9pfs: use error_report() instead of fprintf(stderr)
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2016-01-22 15:12:17 +01:00
Wei Liu
00588a0aa2 9pfs: introduce V9fsVirtioState
V9fsState now only contains generic fields. Introduce V9fsVirtioState
for virtio transport.  Change virtio-pci and virtio-ccw to use
V9fsVirtioState.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-12 11:04:14 +05:30
Wei Liu
2a0c56aa4c 9pfs: factor out v9fs_device_{,un}realize_common
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:33:24 +05:30
Wei Liu
60ce86c714 9pfs: rename virtio-9p.c to 9p.c
Now that file only contains generic code.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:32:13 +05:30
Wei Liu
72a189770a 9pfs: rename virtio_9p_set_fd_limit to use v9fs_ prefix
It's not virtio specific.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
2016-01-08 15:31:49 +05:30
Wei Liu
0192cc5d79 9pfs: move handle_9p_output and make it static function
It's only used in virtio device.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:31:25 +05:30
Wei Liu
4b311c5f0b 9pfs: export pdu_{submit,alloc,free}
They will be used in later patches.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:30:39 +05:30
Wei Liu
0d3716b4e6 9pfs: factor out virtio_9p_push_and_notify
The new function resides in virtio specific file.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:30:03 +05:30
Wei Liu
ebe74f8ba2 9pfs: break out 9p.h from virtio-9p.h
Move out generic definitions from virtio-9p.h to 9p.h. Fix header
inclusions.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:25:30 +05:30
Wei Liu
592707af7f 9pfs: break out virtio_init_iov_from_pdu
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:23:02 +05:30
Wei Liu
f657b17a63 9pfs: factor out pdu_push_and_notify
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:20:02 +05:30
Wei Liu
fe9fa96d7c 9pfs: factor out virtio_pdu_{,un}marshal
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 15:19:40 +05:30
Wei Liu
0e2082d9e5 9pfs: make pdu_{,un}marshal proper functions
Factor out v9fs_iov_v{,un}marshal. Implement pdu_{,un}marshal with those
functions.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:53:39 +05:30
Wei Liu
dc295f8353 9pfs: PDU processing functions should start pdu_ prefix
This matches naming convention of pdu_marshal and pdu_unmarshal.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:35:59 +05:30
Wei Liu
ad38ce9ed1 9pfs: PDU processing functions don't need to take V9fsState as argument
V9fsState can be referenced by pdu->s. Initialise that in device
realization function.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:35:17 +05:30
Wei Liu
2209bd050a fsdev: rename virtio-9p-marshal.{c,h} to 9p-iov-marshal.{c,h}
And rename v9fs_marshal to v9fs_iov_marshal, v9fs_unmarshal to
v9fs_iov_unmarshal.

The rationale behind this change is that, this marshalling interface is
used both by virtio and proxy helper. Renaming files and functions to
reflect the true nature of this interface.

Xen transport is going to have its own marshalling interface.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 14:35:06 +05:30
Wei Liu
71042cffc0 9pfs: remove dead code
Some structures in virtio-9p.h have been unused since 2011 when relevant
functions switched to use coroutines.

The declaration of pdu_packunpack and function do_pdu_unpack are
useless.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:56:03 +05:30
Wei Liu
756cb74a59 9pfs: merge hw/virtio/virtio-9p.h into hw/9pfs/virtio-9p.h
The deleted file only contained V9fsConf which wasn't virtio specific.
Merge that to the general header of 9pfs.

Fixed header inclusions as I went along.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:48:11 +05:30
Wei Liu
267ae092e2 9pfs: rename virtio-9p-xattr{,-user}.{c,h} to 9p-xattr{,-user}.{c,h}
These three files are not virtio specific. Rename them to generic
names.

Fix comments and header inclusion in various files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:47:35 +05:30
Wei Liu
364031f179 9pfs: rename virtio-9p-synth.{c,h} to 9p-synth.{c,h}
These two files are not virtio specific. Rename them to use generic
names.

Fix includes in various C files. Change define guards and comments
in header files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:40:55 +05:30
Wei Liu
494a8ebe71 9pfs: rename virtio-9p-proxy.{c,h} to 9p-proxy.{c,h}
Those two files are not virtio specific. Rename them to use generic
names.

Fix includes in various C files. Change define guards and comments
in header files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:38:15 +05:30
Wei Liu
d57b78002c 9pfs: rename virtio-9p-posix-acl.c to 9p-posix-acl.c
This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:37:32 +05:30
Wei Liu
f00d4f596b 9pfs: rename virtio-9p-local.c to 9p-local.c
This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:36:44 +05:30
Wei Liu
3b9ca04653 9pfs: rename virtio-9p-handle.c to 9p-handle.c
This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:35:46 +05:30
Wei Liu
fe52840c87 9pfs: rename virtio-9p-coth.{c,h} to coth.{c,h}
Those two files are not virtio specific. Rename them to use generic
names.

Fix includes in various C files. Change define guards and comments in
header files.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2016-01-08 12:04:43 +05:30
Greg Kurz
4b3a4f2d45 virtio-9p: use accessor to get thread_pool
The aio_context_new() function does not allocate a thread pool. This is
deferred to the first call to the aio_get_thread_pool() accessor. It is
hence forbidden to access the thread_pool field directly, as it may be
NULL. The accessor *must* be used always.

Fixes: ebac1202c9
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Cc: qemu-stable@nongnu.org
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2015-12-23 10:56:58 +01:00
Greg Kurz
6cecf09373 virtio-9p-device: add minimal unrealize handler
Since commit 4652f1640e "virtio-9p: add savevm
handlers", if the user hot-unplugs a quiescent 9p device and live
migrates, the source QEMU crashes before migration completetion...
This happens because virtio-9p devices have a realize handler which
calls virtio_init() and register_savevm().  Both calls store pointers
to the device internals, that get dereferenced during migration even
if the device got unplugged.

This patch simply adds an unrealize handler to perform minimal
cleanup and avoid the crash.  Hot unplug of non-quiescent 9p devices
is still not supported in QEMU, and not supported by linux guests
either.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20151208155457.27775.69441.stgit@bahia.huguette.org
[PMM: rewrapped long lines in commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-12-10 10:46:22 +00:00
Paolo Bonzini
ebac1202c9 virtio-9p: use QEMU thread pool
The QEMU thread pool already has a mechanism to invoke callbacks in the main
thread.  It does not need an EventNotifier and it is more efficient too.
Use it instead of GAsyncQueue + GThreadPool + glue.

As a side effect, it silences Coverity's complaint about an unchecked
return value for event_notifier_init.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
(removed no more needed #include <glib.h> from virtio-9p-coth.h)
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
2015-11-30 12:36:12 +01:00
Greg Kurz
4652f1640e virtio-9p: add savem handlers
We don't support migration of mounted 9p shares. This is handled by a
migration blocker.

One would expect, however, to be able to migrate if the share is unmounted.
Unfortunately virtio-9p-device does not register savevm handlers at all !
Migration succeeds and leaves the guest with a dangling device...

This patch simply registers migration handlers for virtio-9p-device. Whether
migration is possible or not still depends on the migration blocker.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-11-12 16:40:14 +02:00
Daniel P. Berrange
10817bf09d coroutine: move into libqemuutil.a library
The coroutine files are currently referenced by the block-obj-y
variable. The coroutine functionality though is already used by
more than just the block code. eg migration code uses coroutine
yield. In the future the I/O channel code will also use the
coroutine yield functionality. Since the coroutine code is nicely
self-contained it can be easily built as part of the libqemuutil.a
library, making it widely available.

The headers are also moved into include/qemu, instead of the
include/block directory, since they are now part of the util
codebase, and the impl was never in the block/ directory
either.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-10-20 14:59:04 +01:00
Jason Wang
9d5b731dd2 virtio: get_features() can fail
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-27 18:11:53 +03:00
Michael S. Tsirkin
cd4bfbb20d virtio-9p: fix any_layout
virtio pci allows any device to have a modern interface,
this in turn requires ANY_LAYOUT support.
Fix up ANY_LAYOUT for virtio-9p.

Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2015-07-27 11:24:48 +03:00
Markus Armbruster
d49b683644 qerror: Move #include out of qerror.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Shannon Zhao
83a84878da virtio-9p-device: move qdev properties into virtio-9p-device.c
As only one place in virtio-9p-device.c uses
DEFINE_VIRTIO_9P_PROPERTIES, there is no need to expose it. Inline it
into virtio-9p-device.c to avoid wrongly use.

Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:34 +02:00
Gerd Hoffmann
019a3edbb2 virtio: make features 64bit wide
Make features 64bit wide everywhere.

On migration a full 64bit guest_features field is sent if one of the
high bits is set, in addition to the lower 32bit guest_features field
which must stay for compatibility reasons.  That way we send the lower
32 feature bits twice, but the code is simpler because we don't have
to split and compose the 64bit features into two 32bit fields.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-01 14:18:55 +02:00
Stefan Weil
0289a412e8 9pfs: Fix warnings from Sparse
Sparse report:

9pfs/virtio-9p.c:1953:9: warning: returning void-valued expression
9pfs/virtio-9p-handle.c:143:5: warning: returning void-valued expression
9pfs/virtio-9p-handle.c:160:5: warning: returning void-valued expression
9pfs/virtio-9p-local.c:384:5: warning: returning void-valued expression
9pfs/virtio-9p-local.c:415:5: warning: returning void-valued expression
9pfs/virtio-9p-proxy.c:672:5: warning: returning void-valued expression
9pfs/virtio-9p-proxy.c:689:5: warning: returning void-valued expression

Cc: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-19 11:11:55 +03:00
Stefan Weil
4ed7b2c3a7 virtio: Fix memory leaks reported by Coverity
All four leaks are similar, so fix them in one patch.
Success path was not doing memory free.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-16 13:32:24 +05:30
Shannon Zhao
25ee9a7fa3 virtfs-proxy: Fix possible overflow
It's detected by coverity. The socket name specified
should fit in the sockadd_un.sun_path. If not abort.

Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-16 13:29:12 +05:30
Shannon Zhao
9005c3b3ef hw/9pfs/virtio-9p-posix-acl: Fix out-of-bounds access
It's detected by coverity. Fix out-of-bounds access of the function mp_dacl_listxattr.

Signed-off-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-13 14:01:24 +05:30
Michael Tokarev
7752efcacf 9pfs-proxy: tiny cleanups in proxy_pwritev and proxy_preadv
Don't compare syscall return with -1, use "<0" condition.
Don't introduce useless local variables when we already
have similar variable
Rename local variable to be consistent with other usages
Finally make the two methods, read and write, to be similar to each other

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-12 15:27:35 +05:30
Michael Tokarev
1b6f85e2cb 9pfs-local: simplify/optimize local_mapped_attr_path()
Omit one unnecessary memory allocation for components
of the path and create the resulting path directly given
lengths of the components.

Do not use basename(3) because there are 2 versions of
this function which differs when argument ends with
slash character, use strrchr() instead so we have
consistent result.  This also makes sure the function
will do the right thing in corner cases (eg, empty
pathname is given), when basename(3) return entirely
another string.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-03-12 15:23:05 +05:30
Michael Tokarev
438940cbc2 9pfs: remove useless return
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-10 08:15:34 +03:00
Cornelia Huck
0cd09c3a6c virtio: feature bit manipulation helpers
Add virtio_{add,clear}_feature helper functions for manipulating a
feature bits variable. This has some benefits over open coding:
- add check that the bit is in a sane range
- make it obvious at a glance what is going on
- have a central point to change when we want to extend feature bits

Convert existing code manipulating features to use the new helpers.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-02-26 13:04:07 +01:00
Michael S. Tsirkin
8744a6a8d5 virtio-9p: use standard headers
Drop code duplicated from standard headers.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
2015-02-26 13:04:04 +01:00
Michael S. Tsirkin
e9600c6ca9 virtio: use standard-headers
Drop a bunch of code duplicated from virtio_config.h and virtio_ring.h.
This makes us rename event index accessors which conflict,
as reusing the ones from virtio_ring.h isn't trivial.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
2015-02-26 13:04:03 +01:00
Mike Day
341774fe6c rcu: introduce RCU-enabled QLIST
Add RCU-enabled variants on the existing bsd DQ facility. Each
operation has the same interface as the existing (non-RCU)
version. Also, each operation is implemented as macro.

Using the RCU-enabled QLIST, existing QLIST users will be able to
convert to RCU without using a different list interface.

Signed-off-by: Mike Day <ncmike@ncultra.org>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16 17:30:19 +01:00
Paolo Bonzini
7911747bd4 rcu: add rcu library
This includes a (mangled) copy of the liburcu code.  The main changes
are: 1) removing dependencies on many other header files in liburcu; 2)
removing for simplicity the tentative busy waiting in synchronize_rcu,
which has limited performance effects; 3) replacing futexes in
synchronize_rcu with QemuEvents for Win32 portability.  The API is
the same as liburcu, so it should be possible in the future to require
liburcu on POSIX systems for example and use our copy only on Windows.

Among the various versions available I chose urcu-mb, which is the
least invasive implementation even though it does not have the
fastest rcu_read_{lock,unlock} implementation.  The urcu flavor can
be changed later, after benchmarking.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:10 +01:00