Commit Graph

19 Commits

Author SHA1 Message Date
Vivek Goyal
c46ef954fa virtiofsd: Add support for extended setxattr
Add the bits to enable support for setxattr_ext if fuse offers it. Do not
enable it by default yet. Let passthrough_ll opt-in. Enabling it by deafult
kind of automatically means that you are taking responsibility of clearing
SGID if ACL is set.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Message-Id: <20210622150852.1507204-4-vgoyal@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Fixed up double def in fuse_common.h
2021-07-05 10:51:26 +01:00
Vivek Goyal
d64907acbf viriofsd: Add support for FUSE_HANDLE_KILLPRIV_V2
This patch adds basic support for FUSE_HANDLE_KILLPRIV_V2. virtiofsd
can enable/disable this by specifying option "-o killpriv_v2/no_killpriv_v2".
By default this is enabled as long as client supports it

Enabling this option helps with performance in write path. Without this
option, currently every write is first preceeded with a getxattr() operation
to find out if security.capability is set. (Write is supposed to clear
security.capability). With this option enabled, server is signing up for
clearing security.capability on every WRITE and also clearing suid/sgid
subject to certain rules. This gets rid of extra getxattr() call for every
WRITE and improves performance. This is true when virtiofsd is run with
option -o xattr.

What does enabling FUSE_HANDLE_KILLPRIV_V2 mean for file server implementation.
It needs to adhere to following rules. Thanks to Miklos for this summary.

- clear "security.capability" on write, truncate and chown unconditionally
- clear suid/sgid in case of following. Note, sgid is cleared only if
  group executable bit is set.
    o setattr has FATTR_SIZE and FATTR_KILL_SUIDGID set.
    o setattr has FATTR_UID or FATTR_GID
    o open has O_TRUNC and FUSE_OPEN_KILL_SUIDGID
    o create has O_TRUNC and FUSE_OPEN_KILL_SUIDGID flag set.
    o write has FUSE_WRITE_KILL_SUIDGID

>From Linux VFS client perspective, here are the requirements.

- caps are always cleared on chown/write/truncate
- suid is always cleared on chown, while for truncate/write it is cleared
  only if caller does not have CAP_FSETID.
- sgid is always cleared on chown, while for truncate/write it is cleared
  only if caller does not have CAP_FSETID as well as file has group execute
  permission.

virtiofsd implementation has not changed much to adhere to above ruls. And
reason being that current assumption is that we are running on Linux
and on top of filesystems like ext4/xfs which already follow above rules.
On write, truncate, chown, seucurity.capability is cleared. And virtiofsd
drops CAP_FSETID if need be and that will lead to clearing of suid/sgid.

But if virtiofsd is running on top a filesystem which breaks above assumptions,
then it will have to take extra actions to emulate above. That's a TODO
for later when need arises.

Note: create normally is supposed to be called only when file does not
      exist. So generally there should not be any question of clearing
      setuid/setgid. But it is possible that after client checks that
      file is not present, some other client creates file on server
      and this race can trigger sending FUSE_CREATE. In that case, if
      O_TRUNC is set, we should clear suid/sgid if FUSE_OPEN_KILL_SUIDGID
      is also set.

v3:
  - Resolved conflicts due to lo_inode_open() changes.
  - Moved capability code in lo_do_open() so that both lo_open() and
    lo_create() can benefit from common code.
  - Dropped changes to kernel headers as these are part of qemu already.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210208224024.43555-3-vgoyal@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-16 17:03:09 +00:00
Markus Armbruster
4bd802b209 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, with the changes
to the following files manually reverted:

    contrib/libvhost-user/libvhost-user-glib.h
    contrib/libvhost-user/libvhost-user.c
    contrib/libvhost-user/libvhost-user.h
    contrib/plugins/hotblocks.c
    contrib/plugins/hotpages.c
    contrib/plugins/howvec.c
    contrib/plugins/lockstep.c
    linux-user/mips64/cpu_loop.c
    linux-user/mips64/signal.c
    linux-user/sparc64/cpu_loop.c
    linux-user/sparc64/signal.c
    linux-user/x86_64/cpu_loop.c
    linux-user/x86_64/signal.c
    target/s390x/gen-features.c
    tests/fp/platform.h
    tests/migration/s390x/a-b-bios.c
    tests/plugin/bb.c
    tests/plugin/empty.c
    tests/plugin/insn.c
    tests/plugin/mem.c
    tests/test-rcu-simpleq.c
    tests/test-rcu-slist.c
    tests/test-rcu-tailq.c
    tests/uefi-test-tools/UefiTestToolsPkg/BiosTablesTest/BiosTablesTest.c

contrib/plugins/, tests/plugin/, and tests/test-rcu-slist.c appear not
to include osdep.h intentionally.  The remaining reverts are the same
as in commit bbfff19688.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113061216.2483385-1-armbru@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Alexander Bulekov <alxndr@bu.edu>
2020-12-10 17:16:44 +01:00
Max Reitz
93e79851ab virtiofsd: Add attr_flags to fuse_entry_param
fuse_entry_param is converted to fuse_attr on the line (by
fill_entry()), so it should have a member that mirrors fuse_attr.flags.

fill_entry() should then copy this fuse_entry_param.attr_flags to
fuse_attr.flags.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201102161859.156603-3-mreitz@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-11-02 19:22:48 +00:00
Alex Williamson
33dc9914ea Revert series: virtiofsd: Announce submounts to the guest
This reverts the following commits due to their basis on a bogus
linux kernel header update:

c93a656f7b ("tests/acceptance: Add virtiofs_submounts.py")
45ced7ca2f ("tests/acceptance/boot_linux: Accept SSH pubkey")
08dce386e7 ("virtiofsd: Announce sub-mount points")
eba8b096c1 ("virtiofsd: Store every lo_inode's parent_dev")
ede24b6be7 ("virtiofsd: Add fuse_reply_attr_with_flags()")
e2577435d3 ("virtiofsd: Add attr_flags to fuse_entry_param")
2f10415abf ("virtiofsd: Announce FUSE_ATTR_FLAGS")
97d741cc96 ("linux/fuse.h: Pull in from Linux")

Cc: Max Reitz <mreitz@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 160385090886.20017.13382256442750027666.stgit@gimli.home
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-10-28 13:17:32 +00:00
Max Reitz
ede24b6be7 virtiofsd: Add fuse_reply_attr_with_flags()
The plain fuse_reply_attr() function does not allow setting
fuse_attr.flags, so add this new function that does.

Make fuse_reply_attr() a wrapper around it.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200909184028.262297-5-mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 18:35:32 +00:00
Max Reitz
e2577435d3 virtiofsd: Add attr_flags to fuse_entry_param
fuse_entry_param is converted to fuse_attr on the line (by
fill_entry()), so it should have a member that mirrors fuse_attr.flags.

fill_entry() should then copy this fuse_entry_param.attr_flags to
fuse_attr.flags.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200909184028.262297-4-mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 18:35:32 +00:00
Stefan Hajnoczi
6dbb716877 virtiofsd: add --rlimit-nofile=NUM option
Make it possible to specify the RLIMIT_NOFILE on the command-line.
Users running multiple virtiofsd processes should allocate a certain
number to each process so that the system-wide limit can never be
exhausted.

When this option is set to 0 the rlimit is left at its current value.
This is useful when a management tool wants to configure the rlimit
itself.

The default behavior remains unchanged: try to set the limit to
1,000,000 file descriptors if the current rlimit is lower.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200501140644.220940-2-stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-01 18:41:55 +01:00
Dr. David Alan Gilbert
988717b46b virtiofsd: Remove fuse_req_getgroups
Remove fuse_req_getgroups that's unused in virtiofsd; it came in
from libfuse but we don't actually use it.  It was called from
fuse_getgroups which we previously removed (but had left it's header
in).

Coverity had complained about null termination in it, but removing
it is the easiest answer.

Fixes: Coverity CID: 1413117 (String not null terminated)
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-10 17:24:43 +00:00
Eryu Guan
d240314a1a virtiofsd: print log only when priority is high enough
Introduce "-o log_level=" command line option to specify current log
level (priority), valid values are "debug info warn err", e.g.

    ./virtiofsd -o log_level=debug ...

So only log priority higher than "debug" will be printed to
stderr/syslog. And the default level is info.

The "-o debug"/"-d" options are kept, and imply debug log level.

Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
dgilbert: Reworked for libfuse's log_func
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
with fix by:
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi
f185621d41 virtiofsd: add --syslog command-line option
Sometimes collecting output from stderr is inconvenient or does not fit
within the overall logging architecture.  Add syslog(3) support for
cases where stderr cannot be used.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
dgilbert: Reworked as a logging function
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi
45018fbb0a virtiofsd: add --print-capabilities option
Add the --print-capabilities option as per vhost-user.rst "Backend
programs conventions".  Currently there are no advertised features.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert
f6f3573c6f virtiofsd: Start wiring up vhost-user
Listen on our unix socket for the connection from QEMU, when we get it
initialise vhost-user and dive into our own loop variant (currently
dummy).

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Xiao Yang
8c3fe75e03 virtiofsd: Remove unused enum fuse_buf_copy_flags
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi
64c6f408a2 virtiofsd: remove unused notify reply support
Notify reply support is unused by virtiofsd.  The code would need to be
updated to validate input buffer sizes.  Remove this unused code since
changes to it are untestable.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi
67aab02272 virtiofsd: remove mountpoint dummy argument
Classic FUSE file system daemons take a mountpoint argument but
virtiofsd exposes a vhost-user UNIX domain socket instead.  The
mountpoint argument is not used by virtiofsd but the user is still
required to pass a dummy argument on the command-line.

Remove the mountpoint argument to clean up the command-line.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert
7387863d03 virtiofsd: Format imported files to qemu style
Mostly using a set like:

indent -nut -i 4 -nlp -br -cs -ce --no-space-after-function-call-names file
clang-format -style=file -i -- file
clang-tidy -fix-errors -checks=readability-braces-around-statements file
clang-format -style=file -i -- file

With manual cleanups.

The .clang-format used is below.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed by: Aleksandar Markovic <amarkovic@wavecomp.com>

Language:        Cpp
AlignAfterOpenBracket: Align
AlignConsecutiveAssignments: false # although we like it, it creates churn
AlignConsecutiveDeclarations: false
AlignEscapedNewlinesLeft: true
AlignOperands:   true
AlignTrailingComments: false # churn
AllowAllParametersOfDeclarationOnNextLine: true
AllowShortBlocksOnASingleLine: false
AllowShortCaseLabelsOnASingleLine: false
AllowShortFunctionsOnASingleLine: None
AllowShortIfStatementsOnASingleLine: false
AllowShortLoopsOnASingleLine: false
AlwaysBreakAfterReturnType: None # AlwaysBreakAfterDefinitionReturnType is taken into account
AlwaysBreakBeforeMultilineStrings: false
BinPackArguments: true
BinPackParameters: true
BraceWrapping:
  AfterControlStatement: false
  AfterEnum:       false
  AfterFunction:   true
  AfterStruct:     false
  AfterUnion:      false
  BeforeElse:      false
  IndentBraces:    false
BreakBeforeBinaryOperators: None
BreakBeforeBraces: Custom
BreakBeforeTernaryOperators: false
BreakStringLiterals: true
ColumnLimit:     80
ContinuationIndentWidth: 4
Cpp11BracedListStyle: false
DerivePointerAlignment: false
DisableFormat:   false
ForEachMacros:   [
  'CPU_FOREACH',
  'CPU_FOREACH_REVERSE',
  'CPU_FOREACH_SAFE',
  'IOMMU_NOTIFIER_FOREACH',
  'QLIST_FOREACH',
  'QLIST_FOREACH_ENTRY',
  'QLIST_FOREACH_RCU',
  'QLIST_FOREACH_SAFE',
  'QLIST_FOREACH_SAFE_RCU',
  'QSIMPLEQ_FOREACH',
  'QSIMPLEQ_FOREACH_SAFE',
  'QSLIST_FOREACH',
  'QSLIST_FOREACH_SAFE',
  'QTAILQ_FOREACH',
  'QTAILQ_FOREACH_REVERSE',
  'QTAILQ_FOREACH_SAFE',
  'QTAILQ_RAW_FOREACH',
  'RAMBLOCK_FOREACH'
]
IncludeCategories:
  - Regex:           '^"qemu/osdep.h'
    Priority:        -3
  - Regex:           '^"(block|chardev|crypto|disas|exec|fpu|hw|io|libdecnumber|migration|monitor|net|qapi|qemu|qom|standard-headers|sysemu|ui)/'
    Priority:        -2
  - Regex:           '^"(elf.h|qemu-common.h|glib-compat.h|qemu-io.h|trace-tcg.h)'
    Priority:        -1
  - Regex:           '.*'
    Priority:        1
IncludeIsMainRegex: '$'
IndentCaseLabels: false
IndentWidth:     4
IndentWrappedFunctionNames: false
KeepEmptyLinesAtTheStartOfBlocks: false
MacroBlockBegin: '.*_BEGIN$' # only PREC_BEGIN ?
MacroBlockEnd:   '.*_END$'
MaxEmptyLinesToKeep: 2
PointerAlignment: Right
ReflowComments:  true
SortIncludes:    true
SpaceAfterCStyleCast: false
SpaceBeforeAssignmentOperators: true
SpaceBeforeParens: ControlStatements
SpaceInEmptyParentheses: false
SpacesBeforeTrailingComments: 1
SpacesInContainerLiterals: true
SpacesInParentheses: false
SpacesInSquareBrackets: false
Standard:        Auto
UseTab:          Never
...

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert
a3e23f3254 virtiofsd: Trim down imported files
There's a lot of the original fuse code we don't need; trim them down.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
with additional trimming by:
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert
ee46c78901 virtiofsd: Pull in upstream headers
Pull in headers fromlibfuse's upstream fuse-3.8.0

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00