fuse_vnop_lookup was using a FUSE_GETATTR operation when looking up "." and
"..", even though the only information it needed was the file type and file
size. "." and ".." are obviously always going to be directories; there's no
need to double check.
Sponsored by: The FreeBSD Foundation
* Eliminate fuse_access_param. Whatever it was supposed to do, it seems
like it was never complete. The only real function it ever seems to have
had was a minor performance optimization, which I've already eliminated.
* Make extended attribute operations obey the allow_other mount option.
* Allow unprivileged access to the SYSTEM extattr namespace when
-o default_permissions is not in use.
* Disallow setextattr and deleteextattr on read-only mounts.
* Add tests for a few more error cases.
Sponsored by: The FreeBSD Foundation
Normally all permission checking is done in the fuse server. But when -o
default_permissions is used, it should be done in the kernel instead. This
commit adds appropriate permission checks through fusefs when -o
default_permissions is used. However, sticky bit checks aren't working yet.
I'll handle those in a follow-up commit.
There are no checks for file flags, because those aren't supported by our
version of the FUSE protocol. Nor is there any support for ACLs, though
that could be added if there were any demand.
PR: 216391
Reported by: hiyorin@gmail.com
Sponsored by: The FreeBSD Foundation
The FUSE protocol includes a way for a server to tell the client that a
negative lookup response is cacheable for a certain amount of time.
PR: 236226
Sponsored by: The FreeBSD Foundation
Follow-up to r346046. These two commits implement fuse cache timeouts for
both entries and attributes. They also remove the vfs.fusefs.lookup_cache
enable sysctl, which is no longer needed now that cache timeouts are
honored.
PR: 235773
Sponsored by: The FreeBSD Foundation
The FUSE protocol allows the server to specify the timeout period for the
client's attribute and entry caches. This commit implements the timeout
period for the attribute cache. The entry cache's timeout period is
currently disabled because it panics, and is guarded by the
vfs.fusefs.lookup_cache_expire sysctl.
PR: 235773
Reported by: cem
Sponsored by: The FreeBSD Foundation
FUSE_LOOKUP, FUSE_GETATTR, FUSE_SETATTR, FUSE_MKDIR, FUSE_LINK,
FUSE_SYMLINK, FUSE_MKNOD, and FUSE_CREATE all return file attributes with a
cache validity period. fusefs will now cache the attributes, if the server
returns a non-zero cache validity period.
This change does _not_ implement finite attr cache timeouts. That will
follow as part of PR 235773.
PR: 235775
Reported by: cem
Sponsored by: The FreeBSD Foundation
VOP_ACCESS was never fully implemented in fusefs. This change:
* Removes the FACCESS_DO_ACCESS flag, which pretty much disabled the whole
vop.
* Removes a quixotic special case for VEXEC on regular files. I don't know
why that was in there.
* Removes another confusing special case for VADMIN.
* Removes the FACCESS_NOCHECKSPY flag. It seemed to be a performance
optimization, but I'm unconvinced that it was a net positive.
* Updates test cases.
This change does NOT implement -o default_permissions. That will be handled
separately.
PR: 236291
Sponsored by: The FreeBSD Foundation
When -o allow_other is not in use, fusefs is supposed to prevent access to
the filesystem by any user other than the one who owns the daemon. Our
fusefs implementation was only enforcing that restriction at the mountpoint
itself. That was usually good enough because lookup usually descends from
the mountpoint. However, there are cases when it doesn't, such as when
using openat relative to a file beneath the mountpoint.
PR: 237052
Sponsored by: The FreeBSD Foundation
These tests were actually fixed by r345398, r345390 and r345392, but I
neglected to reenable them. Too bad googletest doesn't have the notion of
an Expected Failure like ATF does.
PR: 236474, 236473
Sponsored by: The FreeBSD Foundation
If a fuse file system returne FOPEN_KEEP_CACHE in the open or create
response, then the client is supposed to _not_ clear its caches for that
file. I don't know why clearing the caches would be the default given that
there's a separate flag to bypass the cache altogether, but that's the way
it is. fusefs(5) will now honor this flag.
Our behavior is slightly different than Linux's because we reuse file
handles. That means that open(2) wont't clear the cache if there's a
reusable file handle, even if the file server wouldn't have sent
FOPEN_KEEP_CACHE had we opened a new file handle like Linux does.
PR: 236560
Sponsored by: The FreeBSD Foundation
If a FUSE daemon returns FOPEN_DIRECT_IO when a file is opened, then it's
allowed to write less data than was requested during a FUSE_WRITE operation
on that file handle. fusefs should simply return a short write to userland.
The old code attempted to resend the unsent data. Not only was that
incorrect behavior, but it did it in an ineffective way, by attempting to
"rewind" the uio and uiomove the unsent data again.
This commit correctly handles short writes by returning directly to
userland if FOPEN_DIRECT_IO was set. If it wasn't set (making the short
write technically a protocol violation), then we resend the unsent data.
But instead of rewinding the uio, just resend the data that's already in the
kernel.
That necessitated a few changes to fuse_ipc.c to reduce the amount of bzero
activity. fusefs may be marginally faster as a result.
PR: 236381
Sponsored by: The FreeBSD Foundation
- init, init -R
- onetime, onetime -R
- 512 and 4k sectors
- encryption only
- encryption and authentication
- configure -r/-R for detached providers
- configure -r/-R for attached providers
- all keys allocated (10, 20 and 30MB provider sizes)
- keys allocated on demand (10, 20 and 30PB provider sizes)
- reading and writing to provider after expansion (10-30MB only)
- checking if metadata in old location is cleared.
Obtained from: Fudo Security
The original fusefs import, r238402, contained a bug in fuse_vnop_close that
could close a directory's file handle while there were still other open file
descriptors. The code looks deliberate, but there is no explanation for it.
This necessitated a workaround in fuse_vnop_readdir that would open a new
file handle if, "for some mysterious reason", that vnode didn't have any
open file handles. r345781 had the effect of causing the workaround to
panic, making the problem more visible.
This commit removes the workaround and the original bug, which also fixes
the panic.
Sponsored by: The FreeBSD Foundation
The FUSE protocol says that FUSE_FLUSH should be send every time a file
descriptor is closed. That's not quite possible in FreeBSD because multiple
file descriptors can share a single struct file, and closef doesn't call
fo_close until the last close. However, we can still send FUSE_FLUSH on
every VOP_CLOSE, which is probably good enough.
There are two purposes for FUSE_FLUSH. One is to allow file systems to
return EIO if they have an error when writing data that's cached
server-side. The other is to release POSIX file locks (which fusefs(5) does
not yet support).
PR: 236405, 236327
Sponsored by: The FreeBSD Foundation
During truncate, fusefs was discarding entire cached blocks, but it wasn't
zeroing out the unused portion of a final partial block. This resulted in
reads returning stale data.
PR: 233783
Reported by: fsx
Sponsored by: The FreeBSD Foundation
Better Makefile syntax.
Note that this commit is to the project branch, but the review concerns the
merge to head.
Sponsored by: The FreeBSD Foundation
This change takes capsicum-test from upstream and applies some local changes to make the
tests work on FreeBSD when executed via Kyua.
The local modifications are as follows:
1. Make `OpenatTest.WithFlag` pass with the new dot-dot lookup behavior in FreeBSD 12.x+.
2. capsicum-test references a set of helper binaries: `mini-me`, `mini-me.noexec`, and
`mini-me.setuid`, as part of the execve/fexecve tests, via execve, fexecve, and open.
It achieves this upstream by assuming `mini-me*` is in the current directory, however,
in order for Kyua to execute `capsicum-test`, it needs to provide a full path to
`mini-me*`. In order to achieve this, I made `capsicum-test` cache the executable's
path from argv[0] in main(..) and use the cached value to compute the path to
`mini-me*` as part of the execve/fexecve testcases.
3. The capsicum-test test suite assumes that it's always being run on CAPABILITIES enabled
kernels. However, there's a chance that the test will be run on a host without a
CAPABILITIES enabled kernel, so we must check for the support before running the tests.
The way to achieve this is to add the relevant `feature_present("security_capabilities")`
check to SetupEnvironment::SetUp() and skip the tests when the support is not available.
While here, add a check for `kern.trap_enotcap` being enabled. As noted by markj@ in
https://github.com/google/capsicum-test/issues/23, this sysctl being enabled can trigger
non-deterministic failures. Therefore, the tests should be skipped if this sysctl is
enabled.
All local changes have been submitted to the capsicum-test project
(https://github.com/google/capsicum-test) and are in various stages of review.
Please see the following pull requests for more details:
1. https://github.com/google/capsicum-test/pull/35
2. https://github.com/google/capsicum-test/pull/41
3. https://github.com/google/capsicum-test/pull/42
Reviewed by: asomers
Discussed with: emaste, markj
Approved by: emaste (mentor)
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D19758
By default, FUSE performs authorization in the server. That means that it's
insecure for the client to reuse FUSE file handles between different users,
groups, or processes. Linux handles this problem by creating a different
FUSE file handle for every file descriptor. FreeBSD can't, due to
differences in our VFS design.
This commit adds credential information to each fuse_filehandle. During
open(2), fusefs will now only reuse a file handle if it matches the exact
same access mode, pid, uid, and gid of the calling process.
PR: 236844
Sponsored by: The FreeBSD Foundation
O_EXEC is useful for fexecve(2) and fchdir(2). Treat it as another fufh
type alongside the existing RDONLY, WRONLY, and RDWR. Prior to r345742 this
would've caused a memory and performance penalty.
PR: 236329
Sponsored by: The FreeBSD Foundation
This test shows how bug 236844 can lead to a privilege escalation when used
with the -o allow_other mount option.
PR: 236844
Sponsored by: The FreeBSD Foundation
Previously fusefs would treat any file opened O_WRONLY as though the
FOPEN_DIRECT_IO flag were set, in an attempt to avoid issuing reads as part
of a RMW write operation on a cached part of the file. However, the FUSE
protocol explicitly allows reads of write-only files for precisely that
reason.
Sponsored by: The FreeBSD Foundation
VOP_GETPAGES is disabled when vfs.fusefs.data_cache_mode=0, causing mmap to
return success but accessing the mapped memory will subsequently segfault.
Sponsored by: The FreeBSD Foundation
Surprisingly, open(..., O_WRONLY | O_CREAT, 0444) should work. POSIX
requires it. But it didn't work in early FUSE implementations. Add a
regression test so that our FUSE driver doesn't make the same mistake.
Sponsored by: The FreeBSD Foundation
fuse_vnop_create must close the newly created file if it can't allocate a
vnode. When it does so, it must use the same file flags for FUSE_RELEASE as
it used for FUSE_OPEN or FUSE_CREATE.
Reported by: Coverity
Coverity CID: 1066204
Sponsored by: The FreeBSD Foundation
The test could occasionally hang if the parent's SIGUSR2 signal arrived
before the child had pause()d. Using POSIX semaphores precludes that
possibility.
Sponsored by: The FreeBSD Foundation
If a FUSE filesystem returns ENOSYS for FUSE_CREATE, then fallback to
FUSE_MKNOD/FUSE_OPEN.
Also, fix a memory leak in the error path of fuse_vnop_create. And do a
little cleanup in fuse_vnop_open.
PR: 199934
Reported by: samm@os2.kiev.ua
Sponsored by: The FreeBSD Foundation
The FUSE protocol allows for LOOKUP to return a cacheable negative response,
which means that the file doesn't exist and the kernel can cache its
nonexistence. As of this commit fusefs doesn't cache the nonexistence, but
it does correctly handle such responses. Prior to this commit attempting to
create a file, even with O_CREAT would fail with ENOENT if the daemon
returned a cacheable negative response.
PR: 236231
Sponsored by: The FreeBSD Foundation
For an unknown reason, fusefs was _always_ sending the fdatasync operation
instead of fsync. Now it correctly sends one or the other.
Also, remove the Fsync.fsync_metadata_only test, along with the recently
removed Fsync.nop. They should never have been added. The kernel shouldn't
keep track of which files have dirty data; that's the daemon's job.
PR: 236473
Sponsored by: The FreeBSD Foundation
It's sufficient to check for /dev/fuse. And due to bug 236647, the module
could be named either fuse or fusefs.
PR: 236647
Sponsored by: The FreeBSD Foundation