summaryrefslogtreecommitdiffhomepage
path: root/pkg/sentry/fsimpl
AgeCommit message (Collapse)Author
2020-06-24Merge release-20200608.0-117-g2189e0a66 (automated)gVisor bot
2020-06-23Clean up hostfs TODOs.Dean Deng
This CL does a handful of things: - Support O_DSYNC, O_SYNC - Support O_APPEND and document an unavoidable race condition - Ignore O_DIRECT; we probably don't want to allow applications to set O_DIRECT on the host fd itself. - Leave a TODO for supporting O_NONBLOCK, which is a simple fix once RWF_NOWAIT is supported. - Get rid of caching TODO; force_page_cache is not configurable for host fs in vfs1 or vfs2 after whitelist fs was removed. - For the remaining TODOs, link to more specific bugs. Fixes #1672. PiperOrigin-RevId: 317985269
2020-06-24Merge release-20200608.0-114-g65a587ded (automated)gVisor bot
2020-06-23Complete inotify IN_EXCL_UNLINK implementation in VFS2.Dean Deng
Events were only skipped on parent directories after their children were unlinked; events on the unlinked file itself need to be skipped as well. As a result, all Watches.Notify() calls need to know whether the dentry where the call came from was unlinked. Updates #1479. PiperOrigin-RevId: 317979476
2020-06-23Merge release-20200608.0-112-g0c628c315 (automated)gVisor bot
2020-06-23Support inotify in vfs2 gofer fs.Dean Deng
Because there is no inode structure stored in the sandbox, inotify watches must be held on the dentry. This would be an issue in the presence of hard links, where multiple dentries would need to share the same set of watches, but in VFS2, we do not support the internal creation of hard links on gofer fs. As a result, we make the assumption that every dentry corresponds to a unique inode. Furthermore, dentries can be cached and then evicted, even if the underlying file has not be deleted. We must prevent this from occurring if there are any watches that would be lost. Note that if the dentry was deleted or invalidated (d.vfsd.IsDead()), we should still destroy it along with its watches. Additionally, when a dentry’s last watch is removed, we cache it if it also has zero references. This way, the dentry can eventually be evicted from memory if it is no longer needed. This is accomplished with a new dentry method, OnZeroWatches(), which is called by Inotify.RmWatch and Inotify.Release. Note that it must be called after all inotify locks are released to avoid violating lock order. Stress tests are added to make sure that inotify operations don't deadlock with gofer.OnZeroWatches. Updates #1479. PiperOrigin-RevId: 317958034
2020-06-23Merge release-20200608.0-106-g38d7b2fe5 (automated)gVisor bot
2020-06-22Only allow regular files, sockets, pipes, and char devices to be imported.Dean Deng
PiperOrigin-RevId: 317796028
2020-06-22Merge release-20200608.0-104-g4573e7d86 (automated)gVisor bot
2020-06-22Check for invalid trailing / when traversing path in gofer OpenAt.Dean Deng
Updates #2923. PiperOrigin-RevId: 317700049
2020-06-22Merge release-20200608.0-101-g00928d142 (automated)gVisor bot
2020-06-21Fix vfs2 extended attributes.Dean Deng
Correct behavior when given zero size arguments and trying to set user.* xattrs on files other than regular files or directories. Updates #2923. PiperOrigin-RevId: 317590409
2020-06-19Merge release-20200608.0-99-gad9f46917 (automated)gVisor bot
2020-06-19Fix bugs in vfs2 to make symlink tests pass.Dean Deng
- Return ENOENT if target path is empty. - Make sure open(2) with O_CREAT|O_EXCL returns EEXIST when necessary. - Correctly update atime in tmpfs using touchATime(). Updates #2923. PiperOrigin-RevId: 317382655
2020-06-19Merge release-20200608.0-97-g8655fb724 (automated)gVisor bot
2020-06-19Fix vfs2 proc/self/fd dirent iteration.Dean Deng
Make proc/self/fd iteration work properly. Also, the comment on kernfs.Inode.IterDirents did not accurately reflect how parameters should be used/were used in kernfs.Inode impls other than fdDir. Updates #2923. PiperOrigin-RevId: 317370325
2020-06-19Merge release-20200608.0-94-ga609fff9d (automated)gVisor bot
2020-06-19Fix vfs2 handling of preadv2/pwritev2 flags.Dean Deng
Check for unsupported flags, and silently support RWF_HIPRI by doing nothing. From pkg/abi/linux/file.go: "gVisor does not implement the RWF_HIPRI feature, but the flag is accepted as a valid flag argument for preadv2/pwritev2." Updates #2923. PiperOrigin-RevId: 317330631
2020-06-19Merge release-20200608.0-93-gf40d023ad (automated)gVisor bot
2020-06-19Don't adjust parent link count if we replace a child dir with another.Dean Deng
Updates #2923. PiperOrigin-RevId: 317314460
2020-06-19Merge release-20200608.0-92-g6b69b955d (automated)gVisor bot
2020-06-19Support all seek options in gofer specialFileFD.Seek.Dean Deng
Updates #2923. PiperOrigin-RevId: 317298186
2020-06-19Merge release-20200608.0-91-g46957ed24 (automated)gVisor bot
2020-06-19Fix synthetic file bugs in gofer fs.Dean Deng
Always check if a synthetic file already exists at a location before creating a file there, and do not try to delete synthetic gofer files from the remote fs. This fixes runsc_ptrace socket tests that create/unlink synthetic, named socket files. Updates #2923. PiperOrigin-RevId: 317293648
2020-06-19Merge release-20200608.0-90-g408f3d2cd (automated)gVisor bot
2020-06-18Fix vfs2 tmpfs link permission checks.Dean Deng
Updates #2923. PiperOrigin-RevId: 317246916
2020-06-18Merge release-20200608.0-83-g3970c1274 (automated)gVisor bot
2020-06-18Remove various uses of 'whitelist'Michael Pratt
Updates #2972 PiperOrigin-RevId: 317113059
2020-06-18Merge release-20200608.0-80-g6e0c17052 (automated)gVisor bot
2020-06-17Implement Sync() to directoriesFabricio Voznika
Updates #1035, #1199 PiperOrigin-RevId: 317028108
2020-06-17Merge release-20200608.0-72-g6d806ee71 (automated)gVisor bot
2020-06-17Remove various uses of 'blacklist'Michael Pratt
Updates #2972 PiperOrigin-RevId: 316942245
2020-06-17Merge release-20200608.0-71-ge5d97cbcc (automated)gVisor bot
2020-06-17Refactor host.canMap.Dean Deng
Simplify the canMap check. We do not have plans to allow mmap for anything beyond regular files, so we can just inline canMap() as a simple file mode check. Updates #1672. PiperOrigin-RevId: 316929654
2020-06-17Merge release-20200608.0-69-g96519e2c9 (automated)gVisor bot
2020-06-17Implement POSIX locksFabricio Voznika
- Change FileDescriptionImpl Lock/UnlockPOSIX signature to take {start,length,whence}, so the correct offset can be calculated in the implementations. - Create PosixLocker interface to make it possible to share the same locking code from different implementations. Closes #1480 PiperOrigin-RevId: 316910286
2020-06-16Merge release-20200608.0-62-g3b0b1f104 (automated)gVisor bot
2020-06-16Miscellaneous VFS2 fixes.Jamie Liu
PiperOrigin-RevId: 316627764
2020-06-12Merge release-20200522.0-145-g77c206e37 (automated)gVisor bot
2020-06-11Add //pkg/sentry/fsimpl/overlay.Jamie Liu
Major differences from existing overlay filesystems: - Linux allows lower layers in an overlay to require revalidation, but not the upper layer. VFS1 allows the upper layer in an overlay to require revalidation, but not the lower layer. VFS2 does not allow any layers to require revalidation. (Now that vfs.MkdirOptions.ForSyntheticMountpoint exists, no uses of overlay in VFS1 are believed to require upper layer revalidation; in particular, the requirement that the upper layer support the creation of "trusted." extended attributes for whiteouts effectively required the upper filesystem to be tmpfs in most cases.) - Like VFS1, but unlike Linux, VFS2 overlay does not attempt to make mutations of the upper layer atomic using a working directory and features like RENAME_WHITEOUT. (This may change in the future, since not having a working directory makes error recovery for some operations, e.g. rmdir, particularly painful.) - Like Linux, but unlike VFS1, VFS2 represents whiteouts using character devices with rdev == 0; the equivalent of the whiteout attribute on directories is xattr trusted.overlay.opaque = "y"; and there is no equivalent to the whiteout attribute on non-directories since non-directories are never merged with lower layers. - Device and inode numbers work as follows: - In Linux, modulo the xino feature and a special case for when all layers are the same filesystem: - Directories use the overlay filesystem's device number and an ephemeral inode number assigned by the overlay. - Non-directories that have been copied up use the device and inode number assigned by the upper filesystem. - Non-directories that have not been copied up use a per-(overlay, layer)-pair device number and the inode number assigned by the lower filesystem. - In VFS1, device and inode numbers always come from the lower layer unless "whited out"; this has the adverse effect of requiring interaction with the lower filesystem even for non-directory files that exist on the upper layer. - In VFS2, device and inode numbers are assigned as in Linux, except that xino and the samefs special case are not supported. - Like Linux, but unlike VFS1, VFS2 does not attempt to maintain memory mapping coherence across copy-up. (This may have to change in the future, as users may be dependent on this property.) - Like Linux, but unlike VFS1, VFS2 uses the overlayfs mounter's credentials when interacting with the overlay's layers, rather than the caller's. - Like Linux, but unlike VFS1, VFS2 permits multiple lower layers in an overlay. - Like Linux, but unlike VFS1, VFS2's overlay filesystem is application-mountable. Updates #1199 PiperOrigin-RevId: 316019067
2020-06-11Don't copy structs with sync.Mutex during initializationFabricio Voznika
During inititalization inode struct was copied around, but it isn't great pratice to copy it around since it contains ref count and sync.Mutex. Updates #1480 PiperOrigin-RevId: 315983788
2020-06-10Merge release-20200522.0-112-g67565078b (automated)gVisor bot
2020-06-09Implement flock(2) in VFS2Fabricio Voznika
LockFD is the generic implementation that can be embedded in FileDescriptionImpl implementations. Unique lock ID is maintained in vfs.FileDescription and is created on demand. Updates #1480 PiperOrigin-RevId: 315604825
2020-06-08Merge release-20200522.0-95-gdc029b4b (automated)gVisor bot
2020-06-08Implement VFS2 tmpfs mount options.Jamie Liu
As in VFS1, the mode, uid, and gid options are supported. Updates #1197 PiperOrigin-RevId: 315340510
2020-06-06Merge release-20200522.0-89-g21b6bc72 (automated)gVisor bot
2020-06-05Implement mount(2) and umount2(2) for VFS2.Rahat Mahmood
This is mostly syscall plumbing, VFS2 already implements the internals of mounts. In addition to the syscall defintions, the following mount-related mechanisms are updated: - Implement MS_NOATIME for VFS2, but only for tmpfs and goferfs. The other VFS2 filesystems don't implement node-level timestamps yet. - Implement the 'mode', 'uid' and 'gid' mount options for VFS2's tmpfs. - Plumb mount namespace ownership, which is necessary for checking appropriate capabilities during mount(2). Updates #1035 PiperOrigin-RevId: 315035352
2020-06-02Merge release-20200522.0-56-g49a9b78f (automated)gVisor bot
2020-06-01Fix VFS2 gofer open(O_CREAT) reference leak.Jamie Liu
gofer.filesystem.createAndOpenChildLocked() doesn't need to take a reference on the new dentry since vfs.FileDescription.Init() will do so. PiperOrigin-RevId: 314242127
2020-06-01Merge release-20200522.0-55-g3a987160 (automated)gVisor bot