SO_NO_CHECK is used to skip the UDP checksum generation on a TX socket
(UDP checksum is optional on IPv4).
Test:
- TestNoChecksum
- SoNoCheckOffByDefault (UdpSocketTest)
- SoNoCheck (UdpSocketTest)
Fixes#3055
PiperOrigin-RevId: 318575215
Also, while we're here, make sure that gofer inotify events are generated when
files are created in remote revalidating mode.
Updates #1479.
PiperOrigin-RevId: 318536354
This change adds a FUSE character device backed by devtmpfs. This
device will be used to establish a connection between the FUSE
server daemon and fusefs. The FileDescriptionImpl methods will
be implemented as we flesh out fusefs some more. The tests assert
that the device can be opened and used.
For TCP sockets, SO_REUSEADDR relaxes the rules for binding addresses.
gVisor/netstack already supported a behavior similar to SO_REUSEADDR, but did
not allow disabling it. This change brings the SO_REUSEADDR behavior closer to
the behavior implemented by Linux and adds a new SO_REUSEADDR disabled
behavior. Like Linux, SO_REUSEADDR is now disabled by default.
PiperOrigin-RevId: 317984380
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
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
Despite what the man page says, linux will return EINVAL when calling
getdents() an a /proc/[tid]/net file corresponding to a zombie task. This
causes readdir() to return a null pointer AND errno=EINVAL.
See fs/proc/proc_net.c:proc_tgid_net_readdir() for where this occurs.
We have tests that recursively read /proc, and are likely to hit this when
running natively, so we must catch and handle this case.
PiperOrigin-RevId: 317674168
The test was expecting that the root mount pathname was "/", but it doesn't
need to be. Only the mount point actually should be "/" (otherwise it is not
the root).
PiperOrigin-RevId: 316968025
- 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
On UDP sockets, SO_REUSEADDR allows multiple sockets to bind to the same
address, but only delivers packets to the most recently bound socket. This
differs from the behavior of SO_REUSEADDR on TCP sockets. SO_REUSEADDR for TCP
sockets will likely need an almost completely independent implementation.
SO_REUSEADDR has some odd interactions with the similar SO_REUSEPORT. These
interactions are tested fairly extensively and all but one particularly odd
one (that honestly seems like a bug) behave the same on gVisor and Linux.
PiperOrigin-RevId: 315844832
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
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
b/36576592 calls out an edge case previously not supported
by HostFS. HostFS is currently being removed, meaning gVisor
supports this feature. Simply add the test to open_test.
PiperOrigin-RevId: 314610226
Splice, setxattr and removexattr should generate events. Note that VFS2 already
generates events for extended attributes.
Updates #1479.
PiperOrigin-RevId: 314244261
Support in other filesystem impls is still needed. Unlike in Linux and vfs1, we
need to plumb inotify down to each filesystem implementation in order to keep
track of links/inode structures properly.
IN_EXCL_UNLINK still needs to be implemented, as well as a few inotify hooks
that are not present in either vfs1 or vfs2. Those will be addressed in
subsequent changes.
Updates #1479.
PiperOrigin-RevId: 313781995