The 9p protocol does not specifically define how server shall behave when
client tries to open a special file, however from security POV it does
make sense for 9p server to prohibit opening any special file on host side
in general. A sane Linux 9p client for instance would never attempt to
open a special file on host side, it would always handle those exclusively
on its guest side. A malicious client however could potentially escape
from the exported 9p tree by creating and opening a device file on host
side.
With QEMU this could only be exploited in the following unsafe setups:
- Running QEMU binary as root AND 9p 'local' fs driver AND 'passthrough'
security model.
or
- Using 9p 'proxy' fs driver (which is running its helper daemon as
root).
These setups were already discouraged for safety reasons before,
however for obvious reasons we are now tightening behaviour on this.
Fixes: CVE-2023-2861
Reported-by: Yanwu Shen <ywsPlz@gmail.com>
Reported-by: Jietao Xiao <shawtao1125@gmail.com>
Reported-by: Jinku Li <jkli@xidian.edu.cn>
Reported-by: Wenbo Shen <shenwenbo@zju.edu.cn>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Message-Id: <E1q6w7r-0000Q0-NM@lizzy.crudebyte.com>
(cherry picked from commit f6b0de53fb)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(Mjt: drop adding qemu_fstat wrapper for 7.2 where wrappers aren't used)
Use g_mkdir() to create a directory on all platforms.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <20220927110632.1973965-27-bmeng.cn@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
API doc comments in QEMU are supposed to be in kerneldoc format, so
convert API doc comments from Doxygen format to kerneldoc format.
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <2e2d46a402560f155de322d95789ba107d728885.1646314856.git.qemu_oss@crudebyte.com>
To allow VirtFS on darwin, we need to check that pthread_fchdir_np is
available, which has only been available since macOS 10.12.
Additionally, virtfs_proxy_helper is disabled on Darwin. This patch
series does not currently provide an implementation of the proxy-helper,
but this functionality could be implemented later on.
Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
[Will Cohen: - Rebase to master]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
[Will Cohen: - Add check for pthread_fchdir_np to virtfs
- Add comments to patch commit
- Note that virtfs_proxy_helper does not work
on macOS
- Fully adjust meson virtfs error note to specify
macOS
- Rebase to master]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Message-Id: <20220227223522.91937-12-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Acked-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
- Guard Linux only headers.
- Add qemu/statfs.h header to abstract over the which
headers are needed for struct statfs
- Define `ENOATTR` only if not only defined
(it's defined in system headers on Darwin).
Signed-off-by: Keno Fischer <keno@juliacomputing.com>
[Michael Roitzsch: - Rebase for NixOS]
Signed-off-by: Michael Roitzsch <reactorcontrol@icloud.com>
While it might at first appear that fsdev/virtfs-proxy-header.c would
need similar adjustment for darwin as file-op-9p here, a later patch in
this series disables virtfs-proxy-helper for non-Linux. Allowing
virtfs-proxy-helper on darwin could potentially be an additional
optimization later.
[Will Cohen: - Fix headers for Alpine
- Integrate statfs.h back into file-op-9p.h
- Remove superfluous header guards from file-opt-9p
- Add note about virtfs-proxy-helper being disabled
on non-Linux for this patch series]
Signed-off-by: Will Cohen <wwcohen@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20220227223522.91937-2-wwcohen@gmail.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Make sure at compile time that the scalar type of the array
requested to be created via P9ARRAY_NEW() matches the scalar
type of the passed auto reference variable (unique pointer).
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <c1965e2a096835dc9e1d4d659dfb15d96755cbe0.1633097129.git.qemu_oss@crudebyte.com>
Implements deep auto free of arrays while retaining common C-style
squared bracket access. Main purpose of this API is to get rid of
error prone individual array deallocation pathes in user code, i.e.
turning something like this:
void doSomething(size_t n) {
Foo *foos = malloc(n * sizeof(Foo));
for (...) {
foos[i].s = malloc(...);
if (...) {
goto out;
}
}
out:
if (...) {
for (...) {
/* deep deallocation */
free(foos[i].s);
}
/* array deallocation */
free(foos);
}
}
into something more simple and safer like:
void doSomething(size_t n) {
P9ARRAY_REF(Foo) foos = NULL;
P9ARRAY_NEW(Foo, foos, n);
for (...) {
foos[i].s = malloc(...);
if (...) {
return; /* array auto freed here */
}
}
/* array auto freed here */
}
Unlike GArray, P9Array does not require special macros, function
calls or struct member dereferencing to access the individual array
elements:
C-array = P9Array: vs. GArray:
for (...) { | for (...) {
... = arr[i].m; | ... = g_array_index(arr, Foo, i).m;
arr[i].m = ... ; | g_array_index(arr, Foo, i).m = ... ;
} | }
So existing C-style array code can be retained with only very little
changes; basically limited to replacing array allocation call and of
course removing individual array deallocation pathes.
In this initial version P9Array only supports the concept of unique
pointers, i.e. it does not support reference counting. The array (and
all dynamically allocated memory of individual array elements) is auto
freed once execution leaves the scope of the reference variable (unique
pointer) associated with the array.
Internally a flex array struct is used in combination with macros
spanned over a continuous memory space for both the array's meta data
(private) and the actual C-array user data (public):
struct P9Array##scalar_type {
size_t len; /* private, hidden from user code */
scalar_type first[]; /* public, directly exposed to user code */
};
Which has the advantage that the compiler automatically takes care
about correct padding, alignment and overall size for all scalar data
types on all systems and that the user space exposed pointer can
directly be translated back and forth between user space C-array
pointer and internal P9Array struct whenever needed, in a type-safe
manner.
This header file is released under MIT license, to allow this file
being used in other C-projects as well. The common QEMU license
GPL2+ might have construed a conflict for other projects.
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Message-Id: <a954ef47b5ac26085a16c5c2aec8695374e0424d.1633097129.git.qemu_oss@crudebyte.com>
have_virtfs_proxy_helper is used from docs/meson.build, and can be
not declared when including it before fsdev/meson.build. This fixes:
../docs/meson.build:54:2: ERROR: Unknown variable "have_virtfs_proxy_helper".
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210120151539.1166252-1-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
I found some style problems while check the code using checkpatch.pl.
This commit fixs the issue below:
ERROR: open brace '{' following struct go on the same line
Signed-off-by: zhouyang <zhouyang789@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201209060735.2760943-1-zhouyang789@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the folder.
Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Alex Bennee <alex.bennee@linaro.org>
Message-Id: <20200917075029.313-2-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Previous patch introduced a performance warning being logged on host
side if client connected with an 'msize' <= 8192. Disable this
performance warning for the synth driver to prevent that warning from
being printed whenever the 9pfs (qtest) test cases are running.
Introduce a new export flag V9FS_NO_PERF_WARN for that purpose, which
might also be used to disable such warnings from the CLI in future.
We could have also prevented the warning by simply raising P9_MAX_SIZE
in virtio-9p-test.c to any value larger than 8192, however in the
context of test cases it makes sense running for edge cases, which
includes the lowest 'msize' value supported by the server which is
4096, hence we want to preserve an msize of 4096 for the test client.
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <E1kEyDy-0006nN-5A@lizzy.crudebyte.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
NULL terminate fs driver options' list, validate_opt() looks for
a null entry to terminate the loop.
Fixes: aee7f3ecd8 ("fsdev: Error out when unsupported option is passed")
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Message-Id: <20200709175848.650400-1-ppandit@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reduce a bit the memory footprint by making the helper_opts[]
array const.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20200305010446.17029-4-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The virtfs-proxy-helper documentation is currently in
fsdev/qemu-trace-stap.texi in Texinfo format, which we
present to the user as:
* a virtfs-proxy-helper manpage
* but not (unusually for QEMU) part of the HTML docs
Convert the documentation to rST format that lives in
the docs/ subdirectory, and present it to the user as:
* a virtfs-proxy-helper manpage
* part of the interop/ Sphinx manual
There are minor formatting changes to suit Sphinx, but no
content changes. In particular I've split the -u and -g
options into each having their own description text.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Greg Kurz <groug@kaod.org>
Message-id: 20200124162606.8787-9-peter.maydell@linaro.org
'err_out' can be removed and be replaced by 'return -errno'
in its only instance in the function.
CC: Greg Kurz <groug@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Acked-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
virtfs-proxy-helper is the only user of libcap; everyone else is using
the simpler libcap-ng API. Switch and remove the configure code to
detect libcap.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
[groug: - drop remaining -lcap from Makefile
- fix error message in configure]
Signed-off-by: Greg Kurz <groug@kaod.org>
'warn' (default): Only log an error message (once) on host if more than one
device is shared by same export, except of that just ignore this config
error though. This is the default behaviour for not breaking existing
installations implying that they really know what they are doing.
'forbid': Like 'warn', but except of just logging an error this
also denies access of guest to additional devices.
'remap': Allows to share more than one device per export by remapping
inodes from host to guest appropriately. To support multiple devices on the
9p share, and avoid qid path collisions we take the device id as input to
generate a unique QID path. The lowest 48 bits of the path will be set
equal to the file inode, and the top bits will be uniquely assigned based
on the top 16 bits of the inode and the device id.
Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com>
[CS: - Rebased to https://github.com/gkurz/qemu/commits/9p-next
(SHA1 7fc4c49e91).
- Added virtfs option 'multidevs', original patch simply did the inode
remapping without being asked.
- Updated hash calls to new xxhash API.
- Updated docs for new option 'multidevs'.
- Fixed v9fs_do_readdir() not having remapped inodes.
- Log error message when running out of prefixes in
qid_path_prefixmap().
- Fixed definition of QPATH_INO_MASK.
- Wrapped qpp_table initialization to dedicated qpp_table_init()
function.
- Dropped unnecessary parantheses in qpp_lookup_func().
- Dropped unnecessary g_malloc0() result checks. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
[groug: - Moved "multidevs" parsing to the local backend.
- Added hint to invalid multidevs option error.
- Turn "remap" into "x-remap". ]
Signed-off-by: Greg Kurz <groug@kaod.org>
It is more convenient to use the return value of the function to notify
errors, rather than to be tied up setting up the &local_err boilerplate.
Signed-off-by: Greg Kurz <groug@kaod.org>
There is no need for signedness on these QID fields for 9p.
Signed-off-by: Antonios Motakis <antonios.motakis@huawei.com>
[CS: - Also make QID type unsigned.
- Adjust donttouch_stat() to new types.
- Adjust trace-events to new types. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Express the complex conditions in Kconfig rather than Makefiles, since Kconfig
is better suited at expressing dependencies and detecting contradictions.
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h). It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.
Include qemu/main-loop.h only where it's needed. Touching it now
recompiles only some 1700 objects. For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the
others, they shrink only slightly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Each fsdriver only supports a subset of the options that can be passed
to -fsdev. Unsupported options are simply ignored. This could cause the
user to erroneously think QEMU has a bug.
Enforce strict checking of supported options for all fsdrivers. This
shouldn't impact libvirt, since it doesn't know about the synth and
proxy fsdrivers.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
It would make sense for these types to be defined in a header file if
we had an API for fsdrivers to register themselves. In practice, we
only have three of them and it is very unlikely we add new ones since
the future of file sharing between host and guest is the upcoming
virtio-fs.
Move the types to qemu-fsdev.c instead since they are only used there.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Header guard symbols should match their file name to make guard
collisions less likely.
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>
Message-Id: <20190315145123.28030-6-armbru@redhat.com>
[Rebase to master: update include/hw/net/ne2000-isa.h]
Most list head structs need not be given a name. In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed. In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct. So clean up everything, not giving a
name except in the rare case where it is necessary.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The "handle" fsdev backend was deprecated in QEMU 2.12.0 with:
commit db3b3c7281
Author: Greg Kurz <groug@kaod.org>
Date: Mon Jan 8 11:18:23 2018 +0100
9pfs: deprecate handle backend
This backend raise some concerns:
- doesn't support symlinks
- fails +100 tests in the PJD POSIX file system test suite [1]
- requires the QEMU process to run with the CAP_DAC_READ_SEARCH
capability, which isn't recommended for security reasons
This backend should not be used and wil be removed. The 'local'
backend is the recommended alternative.
[1] https://www.tuxera.com/community/posix-test-suite/
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
It has passed the two release cooling period without any complaint.
Remove it now.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Calling error_report() from within a function that takes an Error **
argument is suspicious. qemu_fsdev_add() does that, and its caller
fsdev_init_func() then fails without setting an error. Its caller
main(), via qemu_opts_foreach(), is fine with it, but clean it up
anyway.
Cc: Greg Kurz <groug@kaod.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Message-Id: <20181017082702.5581-32-armbru@redhat.com>
hw/9pfs/Makefile.objs uses CONFIG_VIRTIO_9P to guard the definition for
FileOperations structs, while fsdev/Makefile.objs uses CONFIG_VIRTIO
to guard the use. Mismatch causes linking to fail when CONFIG_VIRTIO
is set but CONFIG_VIRTIO_9P is not.
Fix it and use if/else to clarify that the two lines are for opposite
conditions.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Fixes: b5dfdb082f
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
basename(3) and dirname(3) modify their argument and may return
pointers to statically allocated memory which may be overwritten by
subsequent calls.
g_path_get_basename and g_path_get_dirname have no such issues, and
therefore more preferable.
Signed-off-by: Julia Suvorova <jusual@mail.ru>
Message-Id: <1519888086-4207-1-git-send-email-jusual@mail.ru>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
qemu-common.h includes qemu/option.h, but most places that include the
former don't actually need the latter. Drop the include, and add it
to the places that actually need it.
While there, drop superfluous includes of both headers, and
separate #include from file comment with a blank line.
This cleanup makes the number of objects depending on qemu/option.h
drop from 4545 (out of 4743) to 284 in my "build everything" tree.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-20-armbru@redhat.com>
[Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.
While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
qemu_co_queue_next does not need to release and re-acquire the mutex,
because the queued coroutine does not run immediately. However, this
does not hold for qemu_co_enter_next. Now that qemu_co_queue_wait
can synchronize (via QemuLockable) with code that is not running in
coroutine context, it's important that code using qemu_co_enter_next
can easily use a standardized locking idiom.
First of all, qemu_co_enter_next must use aio_co_wake to restart the
coroutine. Second, the function gains a second argument, a QemuLockable*,
and the comments of qemu_co_queue_next and qemu_co_queue_restart_all
are adjusted to clarify the difference.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20180203153935.8056-5-pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
This patch changes some error messages in the backend init code and
convert backends to propagate QEMU Error objects instead of calling
error_report().
One notable improvement is that the local backend now provides a more
detailed error report when it fails to open the shared directory.
Signed-off-by: Greg Kurz <groug@kaod.org>
This patch changes some error messages in the backend opts parsing
code and convert backends to propagate QEMU Error objects instead
of calling error_report().
Signed-off-by: Greg Kurz <groug@kaod.org>
@rpath and @sock_name are not freed and leaked.
[groug, not really leaked since the program exits just after that. But it
is always good practice to free allocated memory]
Signed-off-by: Zhipeng Lu <lu.zhipeng@zte.com.cn>
Signed-off-by: Greg Kurz <groug@kaod.org>
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>
throttle_config() cancels the timers of the calling BlockBackend. This
doesn't make sense because other BlockBackends in the group remain
untouched. There's no need to cancel the timers in the one specific
BlockBackend so let's not do that. Throttled requests will run as
scheduled and future requests will follow the new configuration. This
also allows a throttle group's configuration to be changed even when it
has no members.
Signed-off-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
