Previously, recvmsg() on a unix stream socket with its peer closed will
never return, with goroutine call trace like this:
...
2 in gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).block
at pkg/sentry/kernel/task_block.go:124
3 in gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).BlockWithDeadline
at pkg/sentry/kernel/task_block.go:69
4 in gvisor.dev/gvisor/pkg/sentry/socket/unix.(*SocketOperations).RecvMsg
at pkg/sentry/socket/unix/unix.go:612
5 in gvisor.dev/gvisor/pkg/sentry/syscalls/linux.recvFrom
at pkg/sentry/syscalls/linux/sys_socket.go:885
6 in gvisor.dev/gvisor/pkg/sentry/syscalls/linux.RecvFrom
at pkg/sentry/syscalls/linux/sys_socket.go:910
...
The issue is caused by that ErrClosedForReceive returned by
unix/transport.queue is turned into nil in
unix.(*EndpointReader).ReadToBlocks():
err.ToError()
As a result, in unix.(*SocketOperations).RecvMsg():
n == 0 and err == nil
We shall differentiate it from another case - no data to read where
ErrWouldBlock shall be returned; and return 0 immediately.
Fixes: #734
Reported-by: chenglang.hy <chenglang.hy@antfin.com>
Signed-off-by: Jianfeng Tan <henry.tjf@antfin.com>
Document limitation of no reasonable implementation for RWF_HIPRI
flag (High Priority Read/Write for block-based file systems).
PiperOrigin-RevId: 264237589
We wrongly parses output interface as gateway address.
The fix is straightforward.
Fixes#638
Signed-off-by: Jianfeng Tan <henry.tjf@antfin.com>
Change-Id: Ia4bab31f3c238b0278ea57ab22590fad00eaf061
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/gvisor/pull/684 from tanjianfeng:fix-638 b940e810367ad1273519bfa594f4371bdd293e83
PiperOrigin-RevId: 264211336
Migrates all (except 3) seqfile implementations to the vfs.DynamicBytesSource
interface. There should not be any change in functionality due to this migration
itself.
Please note that the following seqfile implementations have not been migrated:
- /proc/filesystems in proc/filesystems.go
- /proc/[pid]/mountinfo in proc/mounts.go
- /proc/[pid]/mounts in proc/mounts.go
This is because these depend on pending changes in /pkg/senty/vfs.
PiperOrigin-RevId: 263880719
This fixes the implementation ambiguity issues when a filesystem
implementation embeds vfs.DefaultDirectoryFD to its directory FD along
with an internal common fileDescription utility.
For similar reasons also removes FileDescriptionDefaultImpl from
DynamicBytesFileDescriptionImpl.
PiperOrigin-RevId: 263795513
SendMsg before this change would copy all the data over into a
new slice even if the underlying socket could only accept a
small amount of data. This is really inefficient with non-blocking
sockets and under high throughput where large writes could get
ErrWouldBlock or if there was say a timeout associated with the sendmsg()
syscall.
With this change we delay copying bytes in till they are needed and only
copy what can be potentially sent/held in the socket buffer. Reducing
the need to repeatedly copy data over.
Also a minor fix to change state FIN-WAIT-1 when shutdown(..., SHUT_WR) is called
instead of when we transmit the actual FIN. Otherwise the socket could remain in
CONNECTED state even though the user has called shutdown() on the socket.
Updates #627
PiperOrigin-RevId: 263430505
Similar to the EPIPE case, we can return the number of bytes written before
ENOSPC was encountered. If the app tries to write more, we can return ENOSPC on
the next write.
PiperOrigin-RevId: 263041648
Now if a process sends an unsupported netlink requests,
an error is returned from the send system call.
The linux kernel works differently in this case. It returns errors in the
nlmsgerr netlink message.
Reported-by: syzbot+571d99510c6f935202da@syzkaller.appspotmail.com
PiperOrigin-RevId: 262690453
Previously we were representing socket addresses as an interface{},
which allowed any type which could be binary.Marshal()ed to be used as
a socket address. This is fine when the address is passed to userspace
via the linux ABI, but is problematic when used from within the sentry
such as by networking procfs files.
PiperOrigin-RevId: 262460640
Endpoint protocol goroutines were previously started as part of
loading the endpoint. This is potentially too soon, as resources used
by these goroutine may not have been loaded. Protocol goroutines may
perform meaningful work as soon as they're started (ex: incoming
connect) which can cause them to indirectly access resources that
haven't been loaded yet.
This CL defers resuming all protocol goroutines until the end of
restore.
PiperOrigin-RevId: 262409429
- Unexport Filesystem/Dentry/Inode.
- Support SEEK_CUR in directoryFD.Seek().
- Hold Filesystem.mu before touching directoryFD.off in
directoryFD.Seek().
- Remove deleted Dentries from their parent directory.childLists.
- Remove invalid FIXMEs.
PiperOrigin-RevId: 262400633
- This also gets rid of pipes for now because pipe does not have vfs2 specific
support yet.
- Added file path resolution logic.
- Fixes testing infrastructure.
- Does not include unit tests yet.
PiperOrigin-RevId: 262213950
syscall.EPOLLET has been defined with different values on amd64 and
arm64(-0x80000000 on amd64, and 0x80000000 on arm64), while unix.EPOLLET
has been unified this value to 0x80000000(golang/go#5328). ref #63
Signed-off-by: Haibo Xu <haibo.xu@arm.com>
Change-Id: Id97d075c4e79d86a2ea3227ffbef02d8b00ffbb8
(Don't worry, this is mostly tests.)
Implemented the following ioctls:
- TIOCSCTTY - set controlling TTY
- TIOCNOTTY - remove controlling tty, maybe signal some other processes
- TIOCGPGRP - get foreground process group. Also enables tcgetpgrp().
- TIOCSPGRP - set foreground process group. Also enabled tcsetpgrp().
Next steps are to actually turn terminal-generated control characters (e.g. C^c)
into signals to the proper process groups, and to send SIGTTOU and SIGTTIN when
appropriate.
PiperOrigin-RevId: 261387276
We can get the mount namespace from the CreateProcessArgs in all cases where we
need it. This also gets rid of kernel.Destroy method, since the only thing it
was doing was DecRefing the mounts.
Removing the need to call kernel.SetRootMountNamespace also allowed for some
more simplifications in the container fs setup code.
PiperOrigin-RevId: 261357060
This is the source of many warnings like:
AtomicRefCount 0x7f5ff84e3500 owned by "fs.Inode" garbage collected with ref count of 1 (want 0)
PiperOrigin-RevId: 261197093
It gets rid of holding state of the io.Reader offset (which is anyways held by
the vfs.FileDescriptor struct. It is also odd using a io.Reader becuase we
using io.ReaderAt to interact with the device. So making a io.ReaderAt wrapper
makes more sense.
Most importantly, it gets rid of the complexity of extracting the file reader
from a regular file implementation and then using it. Now we can just use the
regular file implementation as a reader which is more intuitive.
PiperOrigin-RevId: 260846927
Adds feature to launch from an open host FD instead of a binary_path.
The FD should point to a valid executable and most likely be statically
compiled. If the executable is not statically compiled, the loader will
search along the interpreter paths, which must be able to be resolved in
the Sandbox's file system or start will fail.
PiperOrigin-RevId: 260756825
This provides the following benefits:
- We can now use pkg/fd package which does not take ownership
of the file descriptor. So it does not close the fd when garbage collected.
This reduces scope of errors from unexpected garbage collection of io.File.
- It enforces the offset parameter in every read call.
It does not affect the fd offset nor is it affected by it. Hence reducing
scope of error of using stale offsets when reading.
- We do not need to serialize the usage of any global file descriptor anymore.
So this drops the mutual exclusion req hence reducing complexity and
congestion.
PiperOrigin-RevId: 260635174
Allocate a larger memory buffer and combine multiple copies into one copy,
to reduce the number of copies from kernel memory to user memory.
Signed-off-by: Hang Su <darcy.sh@antfin.com>
This introduces two new types of Emitters:
1. MultiEmitter, which will forward events to other registered Emitters, and
2. RateLimitedEmitter, which will forward events to a wrapped Emitter, subject
to given rate limits.
The methods in the eventchannel package itself act like a multiEmitter, but is
not actually an Emitter. Now we have a DefaultEmitter, and the methods in
eventchannel simply forward calls to the DefaultEmitter.
The unimplemented syscall handler now uses a RateLimetedEmitter that wraps the
DefaultEmitter.
PiperOrigin-RevId: 260612770
Jianfeng Tan
Tamir Duberstein
Zach Koopmans
Jianfeng Tan
Kevin Krakauer
Andrei Vagin
Ayush Ranjan
Bhasker Hariharan
Jamie Liu
Fabricio Voznika
Nicolas Lacasse
Haibo Xu
Rahat Mahmood
gVisor bot
Michael Pratt
Ian Lewis
Hang Su