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>
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>
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>
- 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>
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>
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>
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>
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>
...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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
