The documentation for EPOLLET (which repeatedly instructs users to read/write
until EAGAIN or short read) suggests that its intent is to only cause an epoll
notification when an FD registered with EPOLLET transitions from not-readable
to readable, or not-writable to writable. In practice, however, the actual
implementation for at least Unix domain sockets will trigger an epoll
notification on *every* send (cf. `net/unix/af_unix.c:unix_stream_sendmsg()` =>
"`other->sk_data_ready(other)`" => `net/core/sock.c:sock_def_readable()`), and
nginx (which registers Unix domain sockets with EPOLLET and - apparently
incorrectly - does *not* read from them until EAGAIN or short read) depends on
this property.
PiperOrigin-RevId: 601911295
A socket queue can contain sockets (others and this one). We have to avoid
taking locks of the same class where it is possible.
PiperOrigin-RevId: 398100744
On Linux these are meant to be equivalent to POLLIN/POLLOUT. Rather
than hack these on in sys_poll etc it felt cleaner to just cleanup
the call sites to notify for both events. This is what linux does
as well.
Fixes#5544
PiperOrigin-RevId: 364859977
The limits for snd/rcv buffers for unix domain socket is controlled by the
following sysctls on linux
- net.core.rmem_default
- net.core.rmem_max
- net.core.wmem_default
- net.core.wmem_max
Today in gVisor we do not expose these sysctls but we do support setting the
equivalent in netstack via stack.Options() method. But AF_UNIX sockets in gVisor
can be used without netstack, with hostinet or even without any networking stack
at all. Which means ideally these sysctls need to live as globals in gVisor.
But rather than make this a big change for now we hardcode the limits in the
AF_UNIX implementation itself (which in itself is better than where we were
before) where it SO_SNDBUF was hardcoded to 16KiB. Further we bump the initial
limit to a default value of 208 KiB to match linux from the paltry 16 KiB we use
today.
Updates #5132
PiperOrigin-RevId: 356665498
This uses the refs_vfs2 template in vfs2 as well as objects common to vfs1 and
vfs2. Note that vfs1-only refcounts are not replaced, since vfs1 will be deleted
soon anyway.
The following structs now use the new tool, with leak check enabled:
devpts:rootInode
fuse:inode
kernfs:Dentry
kernfs:dir
kernfs:readonlyDir
kernfs:StaticDirectory
proc:fdDirInode
proc:fdInfoDirInode
proc:subtasksInode
proc:taskInode
proc:tasksInode
vfs:FileDescription
vfs:MountNamespace
vfs:Filesystem
sys:dir
kernel:FSContext
kernel:ProcessGroup
kernel:Session
shm:Shm
mm:aioMappable
mm:SpecialMappable
transport:queue
And the following use the template, but because they currently are not leak
checked, a TODO is left instead of enabling leak check in this patch:
kernel:FDTable
tun:tunEndpoint
Updates #1486.
PiperOrigin-RevId: 328460377
Currently, Send() will copy data into a new byte slice without regard to the
original size. Size checks should be performed before the allocation takes
place.
Note that for the sake of performance, we avoid putting the buffer
allocation into the critical section. As a result, the size checks need to be
performed again within Enqueue() in case the limit has changed.
PiperOrigin-RevId: 292058147
* Rename syncutil to sync.
* Add aliases to sync types.
* Replace existing usage of standard library sync package.
This will make it easier to swap out synchronization primitives. For example,
this will allow us to use primitives from github.com/sasha-s/go-deadlock to
check for lock ordering violations.
Updates #1472
PiperOrigin-RevId: 289033387
For SOCK_STREAM type unix socket, we shall return ECONNRESET if peer is
closed with data not read.
We explictly set a flag when closing one end, to differentiate from
just shutdown (where zero shall be returned).
Fixes: #735
Signed-off-by: Jianfeng Tan <henry.tjf@antfin.com>
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
Based on the guidelines at
https://opensource.google.com/docs/releasing/authors/.
1. $ rg -l "Google LLC" | xargs sed -i 's/Google LLC.*/The gVisor Authors./'
2. Manual fixup of "Google Inc" references.
3. Add AUTHORS file. Authors may request to be added to this file.
4. Point netstack AUTHORS to gVisor AUTHORS. Drop CONTRIBUTORS.
Fixes#209
PiperOrigin-RevId: 245823212
Change-Id: I64530b24ad021a7d683137459cafc510f5ee1de9
Connectionless Unix sockets (DGRAM Unix sockets created with the socket system
call) inherently only have a read queue. They do not establish bidirectional
connections, instead, the connect system call only sets a default send
location. Writes give the data to the other endpoint which has its own read
queue.
To simplify the code, connectionless Unix sockets still get read and write
queues, but the write queue is a dummy and never waited on. The read queue is
the connectionless endpoint's queue. This change fixes a bug where the dummy
queue was incorrectly set as the read queue and the endpoint's queue was
incorrectly set as the write queue. This meant that read notifications went
to the dummy queue and were black holed.
PiperOrigin-RevId: 225921042
Change-Id: I8d9059def787a2c3c305185b92d05093fbd2be2a
Previously this code used the tcpip error space. Since it is no longer part of
netstack, it can use the sentry's error space (except for a few cases where
there is still some shared code. This reduces the number of error space
conversions required for hot Unix socket operations.
PiperOrigin-RevId: 218541611
Change-Id: I3d13047006a8245b5dfda73364d37b8a453784bb
This allows us to release messages in the queue when all users close.
PiperOrigin-RevId: 218033550
Change-Id: I2f6e87650fced87a3977e3b74c64775c7b885c1b