- 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
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
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
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
Metadata was useful for debugging and safety, but enough tests exist that we
should see failures when (de)serialization is broken. It made stack
initialization more cumbersome and it's also getting in the way of ip6tables.
PiperOrigin-RevId: 317210653
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
- 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
In order to make sure all aio goroutines have stopped during S/R, a new
WaitGroup was added to TaskSet, analagous to runningGoroutines. This WaitGroup
is incremented with each aio goroutine, and waited on during kernel.Pause.
The old VFS1 aio code was changed to use this new WaitGroup, rather than
fs.Async. The only uses of fs.Async are now inode and mount Release operations,
which do not call fs.Async recursively. This fixes a lock-ordering violation
that can cause deadlocks.
Updates #1035.
PiperOrigin-RevId: 316689380
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
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
When I do high-performance networking,
the value of wmem_max is often set very high,
specially for 10/25/50 Gigabit NIC.
I think maybe this restriction is not suitable.
Signed-off-by: Bin Lu <bin.lu@arm.com>
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
When the file closes, it attempts to write dirty cached
attributes to the file. This should not be done when the
mount is readonly.
PiperOrigin-RevId: 315585058
findAvailableLocked() may return a non-aligned FileRange.End after expansion
since it may round FileRange.Start down to a hugepage boundary.
PiperOrigin-RevId: 315520321
Run vs. exec, VFS1 vs. VFS2 were executable lookup were
slightly different from each other. Combine them all
into the same logic.
PiperOrigin-RevId: 315426443
Netstack has traditionally parsed headers on-demand as a packet moves up the
stack. This is conceptually simple and convenient, but incompatible with
iptables, where headers can be inspected and mangled before even a routing
decision is made.
This changes header parsing to happen early in the incoming packet path, as soon
as the NIC gets the packet from a link endpoint. Even if an invalid packet is
found (e.g. a TCP header of insufficient length), the packet is passed up the
stack for proper stats bookkeeping.
PiperOrigin-RevId: 315179302
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
This analysis also catches a potential bug, which is a split on mapPhysical.
This would have led to potential guest-exit during Mapping (although this
would have been handled by the now-unecessary retryInGuest loop).
PiperOrigin-RevId: 315025106
This change has multiple small components.
First, the chunk size is bumped to 1GB in order to avoid creating excessive
VMAs in the Sentry, which can lead to VMA exhaustion (and hitting limits).
Second, gap-tracking is added to the usage set in order to efficiently scan
for available regions.
Third, reclaim is moved to a simple segment set. This is done to allow the
order of reclaim to align with the Allocate order (which becomes much more
complex when trying to track a "max page" as opposed to "min page", so we
just track explicit segments instead, which should make reclaim scanning
faster anyways).
Finally, the findAvailable function attempts to scan from the top-down, in
order to maximize opportunities for VMA merging in applications (hopefully
preventing the same VMA exhaustion that can affect the Sentry).
PiperOrigin-RevId: 315009249
The current task can share its fdtable with a few other tasks,
but after exec, this should be a completely separate process.
PiperOrigin-RevId: 314999565
For TCP sockets gVisor incorrectly returns EAGAIN when no ephemeral ports are
available to bind during a connect. Linux returns EADDRNOTAVAIL. This change
fixes gVisor to return the correct code and adds a test for the same.
This change also fixes a minor bug for ping sockets where connect() would fail
with EINVAL unless the socket was bound first.
Also added tests for testing UDP Port exhaustion and Ping socket port
exhaustion.
PiperOrigin-RevId: 314988525
Dean Deng
gVisor bot
Andrei Vagin
Kevin Krakauer
Ting-Yu Wang
Michael Pratt
Bhasker Hariharan
Fabricio Voznika
Jamie Liu
Nicolas Lacasse
Bin Lu
Nayana Bidari
Gaurav Singh
Rahat Mahmood
Adin Scannell