The error set in the loop in createAt was being masked
by other errors declared with ":=". This allowed an
ErrResolveViaReadlink error to escape, which can cause
a sentry panic.
Added test case which repros without the fix.
PiperOrigin-RevId: 257061767
BounceToKernel will make vCPU quit from guest ring3 to guest ring0, but
vCPUWaiter is not cleared when we unlock the vCPU, when next time this vCPU
enter guest mode ring3, vCPU may enter guest mode with vCPUWaiter bit setted,
this will cause the following BounceToKernel to this vCPU hangs at
waitUntilNot.
Halt may workaroud this issue, because halt process will reset vCPU status into
vCPUUser, and notify all waiter for vCPU state change, but if there is no
exception or syscall in this period, BounceToKernel will hang at waitUntilNot.
PiperOrigin-RevId: 256299660
This renames FDMap to FDTable and drops the kernel.FD type, which had an entire
package to itself and didn't serve much use (it was freely cast between types,
and served as more of an annoyance than providing any protection.)
Based on BenchmarkFDLookupAndDecRef-12, we can expect 5-10 ns per lookup
operation, and 10-15 ns per concurrent lookup operation of savings.
This also fixes two tangential usage issues with the FDMap. Namely, non-atomic
use of NewFDFrom and associated calls to Remove (that are both racy and fail to
drop the reference on the underlying file.)
PiperOrigin-RevId: 256285890
Adds support level documentation for all syscalls. Removes the Undocumented
utility function to discourage usage while leaving SupportUndocumented as the
default support level for Syscall structs.
PiperOrigin-RevId: 256281927
fileOpAt holds references on the Dirents passed as arguments to the callback,
and drops refs when finished, so we don't need to DecRef those Dirents
ourselves
However, all Dirents that we get from FindInode/FindLink must be DecRef'd.
This CL cleans up the ref-counting logic, and fixes some refcount issues in the
process.
PiperOrigin-RevId: 256220882
Fix two leaks for connectionless Unix sockets:
* Double connect: Subsequent connects would leak a reference on the previously
connected endpoint.
* Close unconnected: Sockets which were not connected at the time of closure
would leak a reference on their receiver.
PiperOrigin-RevId: 256070451
These syscalls require filesystem support that gVisor does not provide, and is
not planning to implement. Their absense should not trigger an event.
PiperOrigin-RevId: 255692871
Right now, if we can't create a stub process, we will see this error:
panic: unable to activate mm: resource temporarily unavailable
It would be better to know the root cause of this "resource temporarily
unavailable".
PiperOrigin-RevId: 255656831
Get/Set pipe size and ioctl support were missing from
overlayfs. It required moving the pipe.Sizer interface
to fs so that overlay could get access.
Fixes#318
PiperOrigin-RevId: 255511125
Addresses obvious typos, in the documentation only.
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/gvisor/pull/443 from Pixep:fix/documentation-spelling 4d0688164eafaf0b3010e5f4824b35d1e7176d65
PiperOrigin-RevId: 255477779
Currently, the overlay dirCache is only used for a single logical use of
getdents. i.e., it is discard when the FD is closed or seeked back to
the beginning.
But the initial work of getting the directory contents can be quite
expensive (particularly sorting large directories), so we should keep it
as long as possible.
This is very similar to the readdirCache in fs/gofer.
Since the upper filesystem does not have to allow caching readdir
entries, the new CacheReaddir MountSourceOperations method controls this
behavior.
This caching should be trivially movable to all Inodes if desired,
though that adds an additional copy step for non-overlay Inodes.
(Overlay Inodes already do the extra copy).
PiperOrigin-RevId: 255477592
The code was wrongly assuming that only read access was
required from the lower overlay when checking for permissions.
This allowed non-writable files to be writable in the overlay.
Fixes#316
PiperOrigin-RevId: 255263686
If we have a symlink whose target does not exist, creating the symlink (either
via 'creat' or 'open' with O_CREAT flag) should create the target of the
symlink. Previously, gVisor would error with EEXIST in this case
PiperOrigin-RevId: 255232944
Credentials are immutable and even before these changes we could read them
without locks, but we needed to take a task lock to get a credential object
from a task object.
It is possible to avoid this lock, if we will guarantee that a credential
object will not be changed after setting it on a task.
PiperOrigin-RevId: 254989492
For files with O_APPEND, a file write operation gets a file size and uses it as
offset to call an inode write operation. This means that all other operations
which can change a file size should be blocked while the write operation doesn't
complete.
PiperOrigin-RevId: 254873771
The tracee is stopped early during process exit, when registers are still
available, allowing the tracer to see where the exit occurred, whereas the
normal exit notifi? cation is done after the process is finished exiting.
Without this option, dumpAndPanic fails to get registers.
PiperOrigin-RevId: 254852917
The previous number was for the arm architecture.
Also change the statx tests to force them to run on gVisor, which would have
caught this issue.
PiperOrigin-RevId: 254846831
We don't have the plumbing for btime yet, so that field is left off. The
returned mask indicates that btime is absent.
Fixes#343
PiperOrigin-RevId: 254575752
Otherwise every call to, say, fs.ContextCanAccessFile() in a benchmark
using contexttest allocates new auth.Credentials, a new
auth.UserNamespace, ...
PiperOrigin-RevId: 254261051
The sendfile syscall's backing doSplice contained a race with regard to
blocking. If the first attempt failed with syserror.ErrWouldBlock and then
the blocking file became ready before registering a waiter, we would just
return the ErrWouldBlock (even if we were supposed to block).
PiperOrigin-RevId: 254114432
Adin Scannell
Nicolas Lacasse
Ayush Ranjan
Andrei Vagin
Ian Lewis
Neel Natu
gVisor bot
Yong He
Ahmet Alp Balkan
Ian Gudger
Fabricio Voznika
Michael Pratt
Rahat Mahmood
Jamie Liu