diff options
| author | Andrei Vagin <avagin@google.com> | 2021-09-01 11:46:02 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-09-01 11:48:23 -0700 |
| commit | 927ea16dd384f675a2ce1456be457a371109c488 (patch) | |
| tree | d4131e5e5b84e0d6629259fd27793693656e8f1d | |
| parent | 5e3a5189152e682f94c745a544993c26e18eb9a2 (diff) | |
unix: handle a case when a buffer is overflowed
Reported-by: syzbot+1aab6800bd14829609b8@syzkaller.appspotmail.com
PiperOrigin-RevId: 394279838
| -rw-r--r-- | pkg/sentry/socket/unix/transport/queue.go | 2 | ||||
| -rw-r--r-- | test/syscalls/linux/socket_unix_stream.cc | 15 |
2 files changed, 16 insertions, 1 deletions
diff --git a/pkg/sentry/socket/unix/transport/queue.go b/pkg/sentry/socket/unix/transport/queue.go index e4de44498..a9cedcf5f 100644 --- a/pkg/sentry/socket/unix/transport/queue.go +++ b/pkg/sentry/socket/unix/transport/queue.go @@ -133,7 +133,7 @@ func (q *queue) Enqueue(ctx context.Context, data [][]byte, c ControlMessages, f free := q.limit - q.used if l > free && truncate { - if free == 0 { + if free <= 0 { // Message can't fit right now. q.mu.Unlock() return 0, false, syserr.ErrWouldBlock diff --git a/test/syscalls/linux/socket_unix_stream.cc b/test/syscalls/linux/socket_unix_stream.cc index 6e9f70f8c..2f3cfc3f3 100644 --- a/test/syscalls/linux/socket_unix_stream.cc +++ b/test/syscalls/linux/socket_unix_stream.cc @@ -181,6 +181,21 @@ TEST_P(StreamUnixSocketPairTest, SetSocketSendBuf) { ASSERT_EQ(quarter_sz, val); } +TEST_P(StreamUnixSocketPairTest, SendBufferOverflow) { + auto sockets = ASSERT_NO_ERRNO_AND_VALUE(NewSocketPair()); + auto s = sockets->first_fd(); + + constexpr int kBufSz = 4096; + std::vector<char> buf(kBufSz * 4); + ASSERT_THAT(RetryEINTR(send)(s, buf.data(), buf.size(), MSG_DONTWAIT), + SyscallSucceeds()); + // The new buffer size should be smaller that the amount of data in the queue. + ASSERT_THAT(setsockopt(s, SOL_SOCKET, SO_SNDBUF, &kBufSz, sizeof(kBufSz)), + SyscallSucceeds()); + ASSERT_THAT(RetryEINTR(send)(s, buf.data(), buf.size(), MSG_DONTWAIT), + SyscallFailsWithErrno(EAGAIN)); +} + TEST_P(StreamUnixSocketPairTest, IncreasedSocketSendBufUnblocksWrites) { auto sockets = ASSERT_NO_ERRNO_AND_VALUE(NewSocketPair()); int sock = sockets->first_fd(); |