Commit Graph

232 Commits

Author SHA1 Message Date
Marc-André Lureau ab4c0996f8 meson: use meson datadir instead of qemu_datadir
When cross-compiling, by default qemu_datadir is 'c:\Program
Files\QEMU', which is not recognized as being an absolute path, and
meson will end up adding the prefix again.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200826110419.528931-6-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-01 08:51:33 -04:00
Stefan Hajnoczi fd9279ec99 virtiofsd: probe unshare(CLONE_FS) and print an error
An assertion failure is raised during request processing if
unshare(CLONE_FS) fails. Implement a probe at startup so the problem can
be detected right away.

Unfortunately Docker/Moby does not include unshare in the seccomp.json
list unless CAP_SYS_ADMIN is given. Other seccomp.json lists always
include unshare (e.g. podman is unaffected):
https://raw.githubusercontent.com/seccomp/containers-golang/master/seccomp.json

Use "docker run --security-opt seccomp=path/to/seccomp.json ..." if the
default seccomp.json is missing unshare.

Cc: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200727190223.422280-4-stefanha@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-08-28 13:34:52 +01:00
Stefan Hajnoczi 1c7cb1f52e virtiofsd: drop CAP_DAC_READ_SEARCH
virtiofsd does not need CAP_DAC_READ_SEARCH because it already has
the more powerful CAP_DAC_OVERRIDE. Drop it from the list of
capabilities.

This is important because container runtimes may not include
CAP_DAC_READ_SEARCH by default. This patch allows virtiofsd to reduce
its capabilities when running inside a Docker container.

Note that CAP_DAC_READ_SEARCH may be necessary again in the future if
virtiofsd starts using open_by_handle_at(2).

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200727190223.422280-2-stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-08-28 13:34:52 +01:00
Sergio Lopez e9a78564a1 virtiofsd: Remove "norace" from cmdline help and docs
Commit 93bb3d8d4c ("virtiofsd: remove symlink fallbacks") removed
the implementation of the "norace" option, so remove it from the
cmdline help and the documentation too.

Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20200717121110.50580-1-slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-08-28 13:34:52 +01:00
Vivek Goyal 88fc107956 virtiofsd: Disable remote posix locks by default
Right now we enable remote posix locks by default. That means when guest
does a posix lock it sends request to server (virtiofsd). But currently
we only support non-blocking posix lock and return -EOPNOTSUPP for
blocking version.

This means that existing applications which are doing blocking posix
locks get -EOPNOTSUPP and fail. To avoid this, people have been
running virtiosd with option "-o no_posix_lock". For new users it
is still a surprise and trial and error takes them to this option.

Given posix lock implementation is not complete in virtiofsd, disable
it by default. This means that posix locks will work with-in applications
in a guest but not across guests. Anyway we don't support sharing
filesystem among different guests yet in virtiofs so this should
not lead to any kind of surprise or regression and will make life
little easier for virtiofs users.

Reported-by: Aa Aa <jimbothom@yandex.com>
Suggested-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-08-28 13:34:52 +01:00
Paolo Bonzini 3f99cf5710 tools/virtiofsd: convert to Meson
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:30:09 -04:00
Dr. David Alan Gilbert 3005c099ef virtiofsd: Allow addition or removal of capabilities
Allow capabilities to be added or removed from the allowed set for the
daemon; e.g.

default:
CapPrm: 00000000880000df
CapEff: 00000000880000df

-o modcaps=+sys_admin

CapPrm: 00000000882000df
CapEff: 00000000882000df

-o modcaps=+sys_admin:-chown

CapPrm: 00000000882000de
CapEff: 00000000882000de

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200629115420.98443-4-dgilbert@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-07-03 16:23:05 +01:00
Dr. David Alan Gilbert 55b22a60cc virtiofsd: Check capability calls
Check the capability calls worked.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Message-Id: <20200629115420.98443-3-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-07-03 16:23:05 +01:00
Dr. David Alan Gilbert b1288dfafb virtiofsd: Terminate capability list
capng_updatev is a varargs function that needs a -1 to terminate it,
but it was missing.

In practice what seems to have been happening is that it's added the
capabilities we asked for, then runs into junk on the stack, so if
we're unlucky it might be adding some more, but in reality it's
failing - but after adding the capabilities we asked for.

Fixes: a59feb483b ("virtiofsd: only retain file system capabilities")
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Message-Id: <20200629115420.98443-2-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-07-03 16:23:05 +01:00
Max Reitz 63659fe74e virtiofsd: Whitelist fchmod
lo_setattr() invokes fchmod() in a rarely used code path, so it should
be whitelisted or virtiofsd will crash with EBADSYS.

Said code path can be triggered for example as follows:

On the host, in the shared directory, create a file with the sticky bit
set and a security.capability xattr:
(1) # touch foo
(2) # chmod u+s foo
(3) # setcap '' foo

Then in the guest let some process truncate that file after it has
dropped all of its capabilities (at least CAP_FSETID):

int main(int argc, char *argv[])
{
    capng_setpid(getpid());
    capng_clear(CAPNG_SELECT_BOTH);
    capng_updatev(CAPNG_ADD, CAPNG_PERMITTED | CAPNG_EFFECTIVE, 0);
    capng_apply(CAPNG_SELECT_BOTH);

    ftruncate(open(argv[1], O_RDWR), 0);
}

This will cause the guest kernel to drop the sticky bit (i.e. perform a
mode change) as part of the truncate (where FATTR_FH is set), and that
will cause virtiofsd to invoke fchmod() instead of fchmodat().

(A similar configuration exists further below with futimens() vs.
utimensat(), but the former is not a syscall but just a wrapper for the
latter, so no further whitelisting is required.)

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1842667
Reported-by: Qian Cai <caiqian@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200608093111.14942-1-mreitz@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-06-17 17:48:38 +01:00
Miklos Szeredi 93bb3d8d4c virtiofsd: remove symlink fallbacks
Path lookup in the kernel has special rules for looking up magic symlinks
under /proc.  If a filesystem operation is instructed to follow symlinks
(e.g. via AT_SYMLINK_FOLLOW or lack of AT_SYMLINK_NOFOLLOW), and the final
component is such a proc symlink, then the target of the magic symlink is
used for the operation, even if the target itself is a symlink.  I.e. path
lookup is always terminated after following a final magic symlink.

I was erronously assuming that in the above case the target symlink would
also be followed, and so workarounds were added for a couple of operations
to handle the symlink case.  Since the symlink can be handled simply by
following the proc symlink, these workardouds are not needed.

Also remove the "norace" option, which disabled the workarounds.

Commit bdfd667883 ("virtiofsd: Fix xattr operations") already dealt with
the same issue for xattr operations.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Message-Id: <20200514140736.20561-1-mszeredi@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-06-01 18:44:27 +01:00
Stefan Hajnoczi 66502bbca3 virtiofsd: drop all capabilities in the wait parent process
All this process does is wait for its child.  No capabilities are
needed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-01 20:05:37 +01:00
Stefan Hajnoczi a59feb483b virtiofsd: only retain file system capabilities
virtiofsd runs as root but only needs a subset of root's Linux
capabilities(7).  As a file server its purpose is to create and access
files on behalf of a client.  It needs to be able to access files with
arbitrary uid/gid owners.  It also needs to be create device nodes.

Introduce a Linux capabilities(7) whitelist and drop all capabilities
that we don't need, making the virtiofsd process less powerful than a
regular uid root process.

  # cat /proc/PID/status
  ...
          Before           After
  CapInh: 0000000000000000 0000000000000000
  CapPrm: 0000003fffffffff 00000000880000df
  CapEff: 0000003fffffffff 00000000880000df
  CapBnd: 0000003fffffffff 0000000000000000
  CapAmb: 0000000000000000 0000000000000000

Note that file capabilities cannot be used to achieve the same effect on
the virtiofsd executable because mount is used during sandbox setup.
Therefore we drop capabilities programmatically at the right point
during startup.

This patch only affects the sandboxed child process.  The parent process
that sits in waitpid(2) still has full root capabilities and will be
addressed in the next patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200416164907.244868-2-stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-01 18:57:31 +01:00
Max Reitz ace0829c0d virtiofsd: Show submounts
Currently, setup_mounts() bind-mounts the shared directory without
MS_REC.  This makes all submounts disappear.

Pass MS_REC so that the guest can see submounts again.

Fixes: 5baa3b8e95
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200424133516.73077-1-mreitz@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Changed Fixes to point to the commit with the problem rather than
          the commit that turned it on
2020-05-01 18:52:17 +01:00
Miklos Szeredi 397ae982f4 virtiofsd: jail lo->proc_self_fd
While it's not possible to escape the proc filesystem through
lo->proc_self_fd, it is possible to escape to the root of the proc
filesystem itself through "../..".

Use a temporary mount for opening lo->proc_self_fd, that has it's root at
/proc/self/fd/, preventing access to the ancestor directories.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Message-Id: <20200429124733.22488-1-mszeredi@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-01 18:46:54 +01:00
Stefan Hajnoczi 8c1d353d10 virtiofsd: stay below fs.file-max sysctl value (CVE-2020-10717)
The system-wide fs.file-max sysctl value determines how many files can
be open.  It defaults to a value calculated based on the machine's RAM
size.  Previously virtiofsd would try to set RLIMIT_NOFILE to 1,000,000
and this allowed the FUSE client to exhaust the number of open files
system-wide on Linux hosts with less than 10 GB of RAM!

Take fs.file-max into account when choosing the default RLIMIT_NOFILE
value.

Fixes: CVE-2020-10717
Reported-by: Yuval Avrahami <yavrahami@paloaltonetworks.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200501140644.220940-3-stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-01 18:41:56 +01:00
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
Philippe Mathieu-Daudé e1cd92d95c tools/virtiofsd/passthrough_ll: Fix double close()
On success, the fdopendir() call closes fd. Later on the error
path we try to close an already-closed fd. This can lead to
use-after-free. Fix by only closing the fd if the fdopendir()
call failed.

Cc: qemu-stable@nongnu.org
Fixes: b39bce121b (add dirp_map to hide lo_dirp pointers)
Reported-by: Coverity (CID 1421933 USE_AFTER_FREE)
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200321120654.7985-1-philmd@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-25 12:31:38 +00:00
Misono Tomohiro bdfd667883 virtiofsd: Fix xattr operations
Current virtiofsd has problems about xattr operations and
they does not work properly for directory/symlink/special file.

The fundamental cause is that virtiofsd uses openat() + f...xattr()
systemcalls for xattr operation but we should not open symlink/special
file in the daemon. Therefore the function is restricted.

Fix this problem by:
 1. during setup of each thread, call unshare(CLONE_FS)
 2. in xattr operations (i.e. lo_getxattr), if inode is not a regular
    file or directory, use fchdir(proc_loot_fd) + ...xattr() +
    fchdir(root.fd) instead of openat() + f...xattr()

    (Note: for a regular file/directory openat() + f...xattr()
     is still used for performance reason)

With this patch, xfstests generic/062 passes on virtiofs.

This fix is suggested by Miklos Szeredi and Stefan Hajnoczi.
The original discussion can be found here:
  https://www.redhat.com/archives/virtio-fs/2019-October/msg00046.html

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Message-Id: <20200227055927.24566-3-misono.tomohiro@jp.fujitsu.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-03 15:13:24 +00:00
Misono Tomohiro 16e15a7308 virtiofsd: passthrough_ll: cleanup getxattr/listxattr
This is a cleanup patch to simplify the following xattr fix and
there is no functional changes.

- Move memory allocation to head of the function
- Unify fgetxattr/flistxattr call for both size == 0 and
  size != 0 case
- Remove redundant lo_inode_put call in error path
  (Note: second call is ignored now since @inode is already NULL)

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Message-Id: <20200227055927.24566-2-misono.tomohiro@jp.fujitsu.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-03 15:13:24 +00:00
Xiao Yang 285eb7a704 virtiofsd: Remove fuse.h and struct fuse_module
All code in fuse.h and struct fuse_module are not used by virtiofsd
so removing them is safe.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-02-21 12:53:17 +00:00
Philippe Mathieu-Daudé 09c086b2a1 tools/virtiofsd/fuse_lowlevel: Fix fuse_out_header::error value
Fix warning reported by Clang static code analyzer:

    CC      tools/virtiofsd/fuse_lowlevel.o
  tools/virtiofsd/fuse_lowlevel.c:195:9: warning: Value stored to 'error' is never read
          error = -ERANGE;
          ^       ~~~~~~~

Fixes: 3db2876
Reported-by: Clang Static Analyzer
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-02-21 12:53:17 +00:00
Philippe Mathieu-Daudé 4e1fb9e7bc tools/virtiofsd/passthrough_ll: Remove unneeded variable assignment
Fix warning reported by Clang static code analyzer:

    CC      tools/virtiofsd/passthrough_ll.o
  tools/virtiofsd/passthrough_ll.c:925:9: warning: Value stored to 'newfd' is never read
          newfd = -1;
          ^       ~~
  tools/virtiofsd/passthrough_ll.c:942:9: warning: Value stored to 'newfd' is never read
          newfd = -1;
          ^       ~~

Fixes: 7c6b66027
Reported-by: Clang Static Analyzer
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-02-21 12:53:17 +00:00
Philippe Mathieu-Daudé d4db6f545d tools/virtiofsd/passthrough_ll: Remove unneeded variable assignment
Fix warning reported by Clang static code analyzer:

    CC      tools/virtiofsd/passthrough_ll.o
  tools/virtiofsd/passthrough_ll.c:1083:5: warning: Value stored to 'saverr' is never read
      saverr = ENOMEM;
      ^        ~~~~~~

Fixes: 7c6b66027
Reported-by: Clang Static Analyzer
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-02-21 12:53:17 +00:00
Dr. David Alan Gilbert 82c1474e68 virtiofsd: Help message fix for 'seconds'
second should be seconds.

Reported-by: Christophe de Dinechin <dinechin@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-02-21 12:53:17 +00:00
Dr. David Alan Gilbert 99ce9a7e60 virtiofsd: do_read missing NULL check
Missing a NULL check if the argument fetch fails.

Fixes: Coverity CID 1413119
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
Dr. David Alan Gilbert 686391112f virtiofsd: load_capng missing unlock
Missing unlock in error path.

Fixes: Covertiy CID 1413123
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
Dr. David Alan Gilbert 6fa249027f virtiofsd: fv_create_listen_socket error path socket leak
If we fail when bringing up the socket we can leak the listen_fd;
in practice the daemon will exit so it's not really a problem.

Fixes: Coverity CID 1413121
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
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
Masayoshi Mizuma 1d59b1b210 virtiofsd: add some options to the help message
Add following options to the help message:
- cache
- flock|no_flock
- norace
- posix_lock|no_posix_lock
- readdirplus|no_readdirplus
- timeout
- writeback|no_writeback
- xattr|no_xattr

Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>

dgilbert: Split cache, norace, posix_lock, readdirplus off
  into our own earlier patches that added the options

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Eryu Guan 9883df8cca virtiofsd: stop all queue threads on exit in virtio_loop()
On guest graceful shutdown, virtiofsd receives VHOST_USER_GET_VRING_BASE
request from VMM and shuts down virtqueues by calling fv_set_started(),
which joins fv_queue_thread() threads. So when virtio_loop() returns,
there should be no thread is still accessing data in fuse session and/or
virtio dev.

But on abnormal exit, e.g. guest got killed for whatever reason,
vhost-user socket is closed and virtio_loop() breaks out the main loop
and returns to main(). But it's possible fv_queue_worker()s are still
working and accessing fuse session and virtio dev, which results in
crash or use-after-free.

Fix it by stopping fv_queue_thread()s before virtio_loop() returns,
to make sure there's no-one could access fuse session and virtio dev.

Reported-by: Qingming Su <qingming.su@linux.alibaba.com>
Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Xiao Yang a931b6861e virtiofsd/passthrough_ll: Pass errno to fuse_reply_err()
lo_copy_file_range() passes -errno to fuse_reply_err() and then fuse_reply_err()
changes it to errno again, so that subsequent fuse_send_reply_iov_nofree() catches
the wrong errno.(i.e. reports "fuse: bad error value: ...").

Make fuse_send_reply_iov_nofree() accept the correct -errno by passing errno
directly in lo_copy_file_range().

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Eryu Guan <eguan@linux.alibaba.com>

dgilbert: Sent upstream and now Merged as aa1185e153f774f1df65
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Dr. David Alan Gilbert fe4c15798a virtiofsd: Convert lo_destroy to take the lo->mutex lock itself
lo_destroy was relying on some implicit knowledge of the locking;
we can avoid this if we create an unref_inode that doesn't take
the lock and then grab it for the whole of the lo_destroy.

Suggested-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi 951b3120db virtiofsd: add --thread-pool-size=NUM option
Add an option to control the size of the thread pool.  Requests are now
processed in parallel by default.

Signed-off-by: Stefan Hajnoczi <stefanha@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 16:41:37 +00:00
Stefan Hajnoczi 28f7a3b026 virtiofsd: fix lo_destroy() resource leaks
Now that lo_destroy() is serialized we can call unref_inode() so that
all inode resources are freed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi cdc497c692 virtiofsd: prevent FUSE_INIT/FUSE_DESTROY races
When running with multiple threads it can be tricky to handle
FUSE_INIT/FUSE_DESTROY in parallel with other request types or in
parallel with themselves.  Serialize FUSE_INIT and FUSE_DESTROY so that
malicious clients cannot trigger race conditions.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi a3d756c5ae virtiofsd: process requests in a thread pool
Introduce a thread pool so that fv_queue_thread() just pops
VuVirtqElements and hands them to the thread pool.  For the time being
only one worker thread is allowed since passthrough_ll.c is not
thread-safe yet.  Future patches will lift this restriction so that
multiple FUSE requests can be processed in parallel.

The main new concept is struct FVRequest, which contains both
VuVirtqElement and struct fuse_chan.  We now have fv_VuDev for a device,
fv_QueueInfo for a virtqueue, and FVRequest for a request.  Some of
fv_QueueInfo's fields are moved into FVRequest because they are
per-request.  The name FVRequest conforms to QEMU coding style and I
expect the struct fv_* types will be renamed in a future refactoring.

This patch series is not optimal.  fbuf reuse is dropped so each request
does malloc(se->bufsize), but there is no clean and cheap way to keep
this with a thread pool.  The vq_lock mutex is held for longer than
necessary, especially during the eventfd_write() syscall.  Performance
can be improved in the future.

prctl(2) had to be added to the seccomp whitelist because glib invokes
it.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
piaojun c465bba2c9 virtiofsd: use fuse_buf_writev to replace fuse_buf_write for better performance
fuse_buf_writev() only handles the normal write in which src is buffer
and dest is fd. Specially if src buffer represents guest physical
address that can't be mapped by the daemon process, IO must be bounced
back to the VMM to do it by fuse_buf_copy().

Signed-off-by: Jun Piao <piaojun@huawei.com>
Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Suggested-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 16:41:37 +00:00
piaojun 9ceaaa15cf virtiofsd: add definition of fuse_buf_writev()
Define fuse_buf_writev() which use pwritev and writev to improve io
bandwidth. Especially, the src bufs with 0 size should be skipped as
their mems are not *block_size* aligned which will cause writev failed
in direct io mode.

Signed-off-by: Jun Piao <piaojun@huawei.com>
Suggested-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 16:41:37 +00:00
Misono Tomohiro 9b610b09b4 virtiofsd: passthrough_ll: Use cache_readdir for directory open
Since keep_cache(FOPEN_KEEP_CACHE) has no effect for directory as
described in fuse_common.h, use cache_readdir(FOPNE_CACHE_DIR) for
diretory open when cache=always mode.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Misono Tomohiro 8e4e41e39e virtiofsd: Fix data corruption with O_APPEND write in writeback mode
When writeback mode is enabled (-o writeback), O_APPEND handling is
done in kernel. Therefore virtiofsd clears O_APPEND flag when open.
Otherwise O_APPEND flag takes precedence over pwrite() and write
data may corrupt.

Currently clearing O_APPEND flag is done in lo_open(), but we also
need the same operation in lo_create(). So, factor out the flag
update operation in lo_open() to update_open_flags() and call it
in both lo_open() and lo_create().

This fixes the failure of xfstest generic/069 in writeback mode
(which tests O_APPEND write data integrity).

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.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
Vivek Goyal 65da453980 virtiofsd: Reset O_DIRECT flag during file open
If an application wants to do direct IO and opens a file with O_DIRECT
in guest, that does not necessarily mean that we need to bypass page
cache on host as well. So reset this flag on host.

If somebody needs to bypass page cache on host as well (and it is safe to
do so), we can add a knob in daemon later to control this behavior.

I check virtio-9p and they do reset O_DIRECT flag.

Signed-off-by: Vivek Goyal <vgoyal@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
Eryu Guan fc1aed0bf9 virtiofsd: convert more fprintf and perror to use fuse log infra
Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Peng Tao e468d4af5f virtiofsd: do not always set FUSE_FLOCK_LOCKS
Right now we always enable it regardless of given commandlines.
Fix it by setting the flag relying on the lo->flock bit.

Signed-off-by: Peng Tao <tao.peng@linux.alibaba.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi c241aa9457 virtiofsd: introduce inode refcount to prevent use-after-free
If thread A is using an inode it must not be deleted by thread B when
processing a FUSE_FORGET request.

The FUSE protocol itself already has a counter called nlookup that is
used in FUSE_FORGET messages.  We cannot trust this counter since the
untrusted client can manipulate it via FUSE_FORGET messages.

Introduce a new refcount to keep inodes alive for the required lifespan.
lo_inode_put() must be called to release a reference.  FUSE's nlookup
counter holds exactly one reference so that the inode stays alive as
long as the client still wants to remember it.

Note that the lo_inode->is_symlink field is moved to avoid creating a
hole in the struct due to struct field alignment.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Miklos Szeredi 9257e514d8 virtiofsd: passthrough_ll: fix refcounting on remove/rename
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi 1222f01555 virtiofsd: rename inode->refcount to inode->nlookup
This reference counter plays a specific role in the FUSE protocol.  It's
not a generic object reference counter and the FUSE kernel code calls it
"nlookup".

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi acefdde73b virtiofsd: prevent races with lo_dirp_put()
Introduce lo_dirp_put() so that FUSE_RELEASEDIR does not cause
use-after-free races with other threads that are accessing lo_dirp.

Also make lo_releasedir() atomic to prevent FUSE_RELEASEDIR racing with
itself.  This prevents double-frees.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi baed65c060 virtiofsd: make lo_release() atomic
Hold the lock across both lo_map_get() and lo_map_remove() to prevent
races between two FUSE_RELEASE requests.  In this case I don't see a
serious bug but it's safer to do things atomically.

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 16:41:37 +00:00
Stefan Hajnoczi e7b337326d virtiofsd: prevent fv_queue_thread() vs virtio_loop() races
We call into libvhost-user from the virtqueue handler thread and the
vhost-user message processing thread without a lock.  There is nothing
protecting the virtqueue handler thread if the vhost-user message
processing thread changes the virtqueue or memory table while it is
running.

This patch introduces a read-write lock.  Virtqueue handler threads are
readers.  The vhost-user message processing thread is a writer.  This
will allow concurrency for multiqueue in the future while protecting
against fv_queue_thread() vs virtio_loop() races.

Note that the critical sections could be made smaller but it would be
more invasive and require libvhost-user changes.  Let's start simple and
improve performance later, if necessary.  Another option would be an
RCU-style approach with lighter-weight primitives.

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 16:41:37 +00:00
Stefan Hajnoczi 620e9d8d9c virtiofsd: use fuse_lowlevel_is_virtio() in fuse_session_destroy()
vu_socket_path is NULL when --fd=FDNUM was used.  Use
fuse_lowlevel_is_virtio() instead.

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 16:41:37 +00:00
Vivek Goyal 0e81414c54 virtiofsd: Support remote posix locks
Doing posix locks with-in guest kernel are not sufficient if a file/dir
is being shared by multiple guests. So we need the notion of daemon doing
the locks which are visible to rest of the guests.

Given posix locks are per process, one can not call posix lock API on host,
otherwise bunch of basic posix locks properties are broken. For example,
If two processes (A and B) in guest open the file and take locks on different
sections of file, if one of the processes closes the fd, it will close
fd on virtiofsd and all posix locks on file will go away. This means if
process A closes the fd, then locks of process B will go away too.

Similar other problems exist too.

This patch set tries to emulate posix locks while using open file
description locks provided on Linux.

Daemon provides two options (-o posix_lock, -o no_posix_lock) to enable
or disable posix locking in daemon. By default it is enabled.

There are few issues though.

- GETLK() returns pid of process holding lock. As we are emulating locks
  using OFD, and these locks are not per process and don't return pid
  of process, so GETLK() in guest does not reuturn process pid.

- As of now only F_SETLK is supported and not F_SETLKW. We can't block
  the thread in virtiofsd for arbitrary long duration as there is only
  one thread serving the queue. That means unlock request will not make
  it to daemon and F_SETLKW will block infinitely and bring virtio-fs
  to a halt. This is a solvable problem though and will require significant
  changes in virtiofsd and kernel. Left as a TODO item for now.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Liu Bo 740b0b700a Virtiofsd: fix memory leak on fuse queueinfo
For fuse's queueinfo, both queueinfo array and queueinfos are allocated in
fv_queue_set_started() but not cleaned up when the daemon process quits.

This fixes the leak in proper places.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Eric Ren <renzhen@linux.alibaba.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Eric Ren fc3f0041b4 virtiofsd: fix incorrect error handling in lo_do_lookup
Signed-off-by: Eric Ren <renzhen@linux.alibaba.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
Liu Bo b7ed733a38 virtiofsd: enable PARALLEL_DIROPS during INIT
lookup is a RO operations, PARALLEL_DIROPS can be enabled.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.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
Masayoshi Mizuma 96814800d2 virtiofsd: Prevent multiply running with same vhost_user_socket
virtiofsd can run multiply even if the vhost_user_socket is same path.

  ]# ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu -o source=/tmp/share &
  [1] 244965
  virtio_session_mount: Waiting for vhost-user socket connection...
  ]# ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu -o source=/tmp/share &
  [2] 244966
  virtio_session_mount: Waiting for vhost-user socket connection...
  ]#

The user will get confused about the situation and maybe the cause of the
unexpected problem. So it's better to prevent the multiple running.

Create a regular file under localstatedir directory to exclude the
vhost_user_socket. To create and lock the file, use qemu_write_pidfile()
because the API has some sanity checks and file lock.

Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Applied fixes from Stefan's review and moved osdep include
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 16:41:37 +00:00
Liu Bo 18a69cbbb6 virtiofsd: add helper for lo_data cleanup
This offers an helper function for lo_data's cleanup.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.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
Liu Bo eb68a33b5f virtiofsd: fix memory leak on lo.source
valgrind reported that lo.source is leaked on quiting, but it was defined
as (const char*) as it may point to a const string "/".

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Liu Bo 61cfc44982 virtiofsd: cleanup allocated resource in se
This cleans up unfreed resources in se on quiting, including
se->virtio_dev, se->vu_socket_path, se->vu_socketfd.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.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
Liu Bo c6de804670 virtiofsd: fix error handling in main()
Neither fuse_parse_cmdline() nor fuse_opt_parse() goes to the right place
to do cleanup.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.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
Jiufei Xue 8a792b034d virtiofsd: support nanosecond resolution for file timestamp
Define HAVE_STRUCT_STAT_ST_ATIM to 1 if `st_atim' is member of `struct
stat' which means support nanosecond resolution for the file timestamp
fields.

Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.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
Dr. David Alan Gilbert 771b01eb76 virtiofsd: Clean up inodes on destroy
Clear out our inodes and fd's on a 'destroy' - so we get rid
of them if we reboot the guest.

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
Miklos Szeredi bfc50a6e06 virtiofsd: passthrough_ll: use hashtable
Improve performance of inode lookup by using a hash table.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.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
Miklos Szeredi 230e777b5e virtiofsd: passthrough_ll: clean up cache related options
- Rename "cache=never" to "cache=none" to match 9p's similar option.

 - Rename CACHE_NORMAL constant to CACHE_AUTO to match the "cache=auto"
   option.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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
Miklos Szeredi 3ca8a2b1c8 virtiofsd: extract root inode init into setup_root()
Inititialize the root inode in a single place.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
dgilbert:
with fix suggested by Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Miklos Szeredi 9de4fab599 virtiofsd: fail when parent inode isn't known in lo_do_lookup()
The Linux file handle APIs (struct export_operations) can access inodes
that are not attached to parents because path name traversal is not
performed.  Refuse if there is no parent in lo_do_lookup().

Also clean up lo_do_lookup() while we're here.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Miklos Szeredi 95d2715791 virtiofsd: rename unref_inode() to unref_inode_lolocked()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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 16:41:37 +00:00
Miklos Szeredi 59aef494be virtiofsd: passthrough_ll: control readdirplus
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Miklos Szeredi ddcbabcb0e virtiofsd: passthrough_ll: disable readdirplus on cache=never
...because the attributes sent in the READDIRPLUS reply would be discarded
anyway.

Signed-off-by: Miklos Szeredi <mszeredi@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
Miklos Szeredi f0ab7d6f78 virtiofsd: passthrough_ll: add renameat2 support
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Dr. David Alan Gilbert 10477ac47f virtiofsd: Kill threads when queues are stopped
Kill the threads we've started when the queues get stopped.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
With improvements by:
Signed-off-by: Eryu Guan <eguan@linux.alibaba.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
Dr. David Alan Gilbert e8556f4909 virtiofsd: Handle hard reboot
Handle a
  mount
  hard reboot (without unmount)
  mount

we get another 'init' which FUSE doesn't normally expect.

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
Dr. David Alan Gilbert c806d6435f virtiofsd: Handle reinit
Allow init->destroy->init  for mount->umount->mount

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
Masayoshi Mizuma 50fb955aa0 virtiofsd: Add timestamp to the log with FUSE_LOG_DEBUG level
virtiofsd has some threads, so we see a lot of logs with debug option.
It would be useful for debugging if we can see the timestamp.

Add nano second timestamp, which got by get_clock(), to the log with
FUSE_LOG_DEBUG level if the syslog option isn't set.

The log is like as:

  # ./virtiofsd -d -o vhost_user_socket=/tmp/vhostqemu0 -o source=/tmp/share0 -o cache=auto
  ...
  [5365943125463727] [ID: 00000002] fv_queue_thread: Start for queue 0 kick_fd 9
  [5365943125568644] [ID: 00000002] fv_queue_thread: Waiting for Queue 0 event
  [5365943125573561] [ID: 00000002] fv_queue_thread: Got queue event on Queue 0

Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Masayoshi Mizuma 36f3846902 virtiofsd: Add ID to the log with FUSE_LOG_DEBUG level
virtiofsd has some threads, so we see a lot of logs with debug option.
It would be useful for debugging if we can identify the specific thread
from the log.

Add ID, which is got by gettid(), to the log with FUSE_LOG_DEBUG level
so that we can grep the specific thread.

The log is like as:

  ]# ./virtiofsd -d -o vhost_user_socket=/tmp/vhostqemu0 -o source=/tmp/share0 -o cache=auto
  ...
  [ID: 00000097]    unique: 12696, success, outsize: 120
  [ID: 00000097] virtio_send_msg: elem 18: with 2 in desc of length 120
  [ID: 00000003] fv_queue_thread: Got queue event on Queue 1
  [ID: 00000003] fv_queue_thread: Queue 1 gave evalue: 1 available: in: 65552 out: 80
  [ID: 00000003] fv_queue_thread: Waiting for Queue 1 event
  [ID: 00000071] fv_queue_worker: elem 33: with 2 out desc of length 80 bad_in_num=0 bad_out_num=0
  [ID: 00000071] unique: 12694, opcode: READ (15), nodeid: 2, insize: 80, pid: 2014
  [ID: 00000071] lo_read(ino=2, size=65536, off=131072)

Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  added rework as suggested by Daniel P. Berrangé during review
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +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 3db2876a01 virtiofsd: fix libfuse information leaks
Some FUSE message replies contain padding fields that are not
initialized by libfuse.  This is fine in traditional FUSE applications
because the kernel is trusted.  virtiofsd does not trust the guest and
must not expose uninitialized memory.

Use C struct initializers to automatically zero out memory.  Not all of
these code changes are strictly necessary but they will prevent future
information leaks if the structs are extended.

Signed-off-by: Stefan Hajnoczi <stefanha@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 16:41:37 +00:00
Stefan Hajnoczi 01a6dc95ec virtiofsd: set maximum RLIMIT_NOFILE limit
virtiofsd can exceed the default open file descriptor limit easily on
most systems.  Take advantage of the fact that it runs as root to raise
the limit.

Signed-off-by: Stefan Hajnoczi <stefanha@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 16:41:37 +00:00
Vivek Goyal ee88465224 virtiofsd: Drop CAP_FSETID if client asked for it
If client requested killing setuid/setgid bits on file being written, drop
CAP_FSETID capability so that setuid/setgid bits are cleared upon write
automatically.

pjdfstest chown/12.t needs this.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
  dgilbert: reworked for libcap-ng
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Dr. David Alan Gilbert 2405f3c0d1 virtiofsd: cap-ng helpers
libcap-ng reads /proc during capng_get_caps_process, and virtiofsd's
sandboxing doesn't have /proc mounted; thus we have to do the
caps read before we sandbox it and save/restore the state.

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
Vivek Goyal f779bc5265 virtiofsd: Parse flag FUSE_WRITE_KILL_PRIV
Caller can set FUSE_WRITE_KILL_PRIV in write_flags. Parse it and pass it
to the filesystem.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi 4f8bde99c1 virtiofsd: add seccomp whitelist
Only allow system calls that are needed by virtiofsd.  All other system
calls cause SIGSYS to be directed at the thread and the process will
coredump.

Restricting system calls reduces the kernel attack surface and limits
what the process can do when compromised.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
with additional entries by:
Signed-off-by: Ganesh Maharaj Mahalingam <ganesh.mahalingam@intel.com>
Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: piaojun <piaojun@huawei.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Eric Ren <renzhen@linux.alibaba.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:37 +00:00
Stefan Hajnoczi 8e1d4ef231 virtiofsd: move to a new pid namespace
virtiofsd needs access to /proc/self/fd.  Let's move to a new pid
namespace so that a compromised process cannot see another other
processes running on the system.

One wrinkle in this approach: unshare(CLONE_NEWPID) affects *child*
processes and not the current process.  Therefore we need to fork the
pid 1 process that will actually run virtiofsd and leave a parent in
waitpid(2).  This is not the same thing as daemonization and parent
processes should not notice a difference.

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 16:41:37 +00:00
Stefan Hajnoczi d74830d12a virtiofsd: move to an empty network namespace
If the process is compromised there should be no network access.  Use an
empty network namespace to sandbox networking.

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 5baa3b8e95 virtiofsd: sandbox mount namespace
Use a mount namespace with the shared directory tree mounted at "/" and
no other mounts.

This prevents symlink escape attacks because symlink targets are
resolved only against the shared directory and cannot go outside it.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Peng Tao <tao.peng@linux.alibaba.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 9f59d175e2 virtiofsd: use /proc/self/fd/ O_PATH file descriptor
Sandboxing will remove /proc from the mount namespace so we can no
longer build string paths into "/proc/self/fd/...".

Keep an O_PATH file descriptor so we can still re-open fds via
/proc/self/fd.

Signed-off-by: Stefan Hajnoczi <stefanha@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
Stefan Hajnoczi 752272da2b virtiofsd: prevent ".." escape in lo_do_readdir()
Construct a fake dirent for the root directory's ".." entry.  This hides
the parent directory from the FUSE client.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 854684bc0b virtiofsd: prevent ".." escape in lo_do_lookup()
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 7099575441 virtiofsd: check input buffer size in fuse_lowlevel.c ops
Each FUSE operation involves parsing the input buffer.  Currently the
code assumes the input buffer is large enough for the expected
arguments.  This patch uses fuse_mbuf_iter to check the size.

Most operations are simple to convert.  Some are more complicated due to
variable-length inputs or different sizes depending on the protocol
version.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 0ba8c3c6fc virtiofsd: validate input buffer sizes in do_write_buf()
There is a small change in behavior: if fuse_write_in->size doesn't
match the input buffer size then the request is failed.  Previously
write requests with 1 fuse_buf element would truncate to
fuse_write_in->size.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi dad157e880 virtiofsd: add fuse_mbuf_iter API
Introduce an API for consuming bytes from a buffer with size checks.
All FUSE operations will be converted to use this safe API instead of
void *inarg.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert e17f7a580e virtiofsd: Pass write iov's all the way through
Pass the write iov pointing to guest RAM all the way through rather
than copying the data.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@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 469f9d2fc4 virtiofsd: Plumb fuse_bufvec through to do_write_buf
Let fuse_session_process_buf_int take a fuse_bufvec * instead of a
fuse_buf;  and then through to do_write_buf - where in the best
case it can pass that straight through to op.write_buf without copying
(other than skipping a header).

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 25dae28c58 virtiofsd: validate path components
Several FUSE requests contain single path components.  A correct FUSE
client sends well-formed path components but there is currently no input
validation in case something went wrong or the client is malicious.

Refuse ".", "..", and paths containing '/' when we expect a path
component.

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
Miklos Szeredi 5fe319a7b1 virtiofsd: passthrough_ll: add fallback for racy ops
We have two operations that cannot be done race-free on a symlink in
certain cases: utimes and link.

Add racy fallback for these if the race-free method doesn't work.  We do
our best to avoid races even in this case:

  - get absolute path by reading /proc/self/fd/NN symlink

  - lookup parent directory: after this we are safe against renames in
    ancestors

  - lookup name in parent directory, and verify that we got to the original
    inode,  if not retry the whole thing

Both utimes(2) and link(2) hold i_lock on the inode across the operation,
so a racing rename/delete by this fuse instance is not possible, only from
other entities changing the filesystem.

If the "norace" option is given, then disable the racy fallbacks.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 73b4d19dfc virtiofsd: passthrough_ll: add fd_map to hide file descriptors
Do not expose file descriptor numbers to clients.  This prevents the
abuse of internal file descriptors (like stdin/stdout).

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Fix from:
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
dgilbert:
  Added lseek
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi b39bce121b virtiofsd: passthrough_ll: add dirp_map to hide lo_dirp pointers
Do not expose lo_dirp pointers to clients.

Signed-off-by: Stefan Hajnoczi <stefanha@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
Stefan Hajnoczi 92fb57b83c virtiofsd: passthrough_ll: add ino_map to hide lo_inode pointers
Do not expose lo_inode pointers to clients.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 25c135727b virtiofsd: passthrough_ll: add lo_map for ino/fh indirection
A layer of indirection is needed because passthrough_ll cannot expose
pointers or file descriptor numbers to untrusted clients.  Malicious
clients could send invalid pointers or file descriptors in order to
crash or exploit the file system daemon.

lo_map provides an integer key->value mapping.  This will be used for
ino and fh fields in the patches that follow.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Vivek Goyal 929cfb7a9a virtiofsd: passthrough_ll: create new files in caller's context
We need to create files in the caller's context. Otherwise after
creating a file, the caller might not be able to do file operations on
that file.

Changed effective uid/gid to caller's uid/gid, create file and then
switch back to uid/gid 0.

Use syscall(setresuid, ...) otherwise glibc does some magic to change EUID
in all threads, which is not what we want.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +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
Stefan Hajnoczi 315616ed50 virtiofsd: add vhost-user.json file
Install a vhost-user.json file describing virtiofsd.  This allows
libvirt and other management tools to enumerate vhost-user backend
programs.

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 0bbd317537 virtiofsd: make -f (foreground) the default
According to vhost-user.rst "Backend program conventions", backend
programs should run in the foregound by default.  Follow the
conventions so libvirt and other management tools can control virtiofsd
in a standard way.

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 cee8e35d43 virtiofsd: add --fd=FDNUM fd passing option
Although --socket-path=PATH is useful for manual invocations, management
tools typically create the UNIX domain socket themselves and pass it to
the vhost-user device backend.  This way QEMU can be launched
immediately with a valid socket.  No waiting for the vhost-user device
backend is required when fd passing is used.

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 eb49d187ef virtiofsd: Fast path for virtio read
Readv the data straight into the guests buffer.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
With fix by:
Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
Reviewed-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert 81bfc42dcf virtiofsd: Add Makefile wiring for virtiofsd contrib
Wire up the building of the virtiofsd in tools.

virtiofsd relies on Linux-specific system calls and seccomp.  Anyone
wishing to port it to other host operating systems should do so
carefully and without reducing security.

Only allow building on Linux hosts.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.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 2f65e69a7f virtiofsd: Keep track of replies
Keep track of whether we sent a reply to a request; this is a bit
paranoid but it means:
  a) We should always recycle an element even if there was an error
     in the request
  b) Never try and send two replies on one queue element

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
Dr. David Alan Gilbert df57ba919e virtiofsd: Send replies to messages
Route fuse out messages back through the same queue elements
that had the command that triggered the request.

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
Dr. David Alan Gilbert b509e1228b virtiofsd: Start reading commands from queue
Pop queue elements off queues, copy the data from them and
pass that to fuse.

  Note: 'out' in a VuVirtqElement is from QEMU
        'in' in libfuse is into the daemon

  So we read from the out iov's to get a fuse_in_header

When we get a kick we've got to read all the elements until the queue
is empty.

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
Dr. David Alan Gilbert 5dcd1f5614 virtiofsd: Poll kick_fd for queue
In the queue thread poll the kick_fd we're passed.

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
Dr. David Alan Gilbert e4c55a3c14 virtiofsd: Start queue threads
Start a thread for each queue when we get notified it's been started.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
fix by:
Signed-off-by: Jun Piao <piaojun@huawei.com>
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 f2cef5fb9a virtiofsd: get/set features callbacks
Add the get/set features callbacks.

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
Dr. David Alan Gilbert 204d8ae57b virtiofsd: Add main virtio loop
Processes incoming requests on the vhost-user fd.

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
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
Dr. David Alan Gilbert d14bf584dd virtiofsd: Open vhost connection instead of mounting
When run with vhost-user options we conect to the QEMU instead
via a socket.  Start this off by creating the socket.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Stefan Hajnoczi 4ff075f72b virtiofsd: add -o source=PATH to help output
The -o source=PATH option will be used by most command-line invocations.
Let's document it!

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 205de006aa virtiofsd: Add options for virtio
Add options to specify parameters for virtio-fs paths, i.e.

   ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-23 16:41:36 +00:00
Vivek Goyal 1b209805f8 virtiofsd: Make fsync work even if only inode is passed in
If caller has not sent file handle in request, then using inode, retrieve
the fd opened using O_PATH and use that to open file again and issue
fsync. This will be needed when dax_flush() calls fsync. At that time
we only have inode information (and not file).

Signed-off-by: Vivek Goyal <vgoyal@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 9776457ca6 vitriofsd/passthrough_ll: fix fallocate() ifdefs
1) Use correct CONFIG_FALLOCATE macro to check if fallocate() is supported.(i.e configure
   script sets CONFIG_FALLOCATE intead of HAVE_FALLOCATE if fallocate() is supported)
2) Replace HAVE_POSIX_FALLOCATE with CONFIG_POSIX_FALLOCATE.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Merged from two of Xiao Yang's patches
2020-01-23 16:41:36 +00:00
Dr. David Alan Gilbert 72c42e2d65 virtiofsd: Trim out compatibility code
virtiofsd only supports major=7, minor>=31; trim out a lot of
old compatibility code.

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
Dr. David Alan Gilbert 09863ebc7e virtiofsd: Fix common header and define for QEMU builds
All of the fuse files include config.h and define GNU_SOURCE
where we don't have either under our build - remove them.
Fixup path to the kernel's fuse.h in the QEMUs world.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-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
Dr. David Alan Gilbert 30d8e49760 virtiofsd: Fix fuse_daemonize ignored return values
QEMU's compiler enables warnings/errors for ignored values
and the (void) trick used in the fuse code isn't enough.
Turn all the return values into a return value on the function.

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>
Tested-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
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 7c6b660272 virtiofsd: Add passthrough_ll
passthrough_ll is one of the examples in the upstream fuse project
and is the main part of our daemon here.  It passes through requests
from fuse to the underlying filesystem, using syscalls as directly
as possible.

From libfuse fuse-3.8.0

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Fixed up 'GPL' to 'GPLv2' as per Dan's comments and consistent
  with the 'LICENSE' file in libfuse;  patch sent to libfuse to fix
  it upstream.
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 2de121f01e virtiofsd: Add fuse_lowlevel.c
fuse_lowlevel is one of the largest files from the library
and does most of the work.  Add it separately to keep the diff
sizes small.
Again this is from upstream fuse-3.8.0

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
Dr. David Alan Gilbert ffcf8d9f86 virtiofsd: Add auxiliary .c's
Add most of the non-main .c files we need from upstream fuse-3.8.0

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
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