diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2013-04-04 16:18:31 +0200 |
|---|---|---|
| committer | Michael Roth <mdroth@linux.vnet.ibm.com> | 2013-04-04 15:17:32 -0500 |
| commit | 27c71355fbf7f999f3fbb8ec42ec88210211b6f4 (patch) | |
| tree | 640d9047ac6a097f911511d2cfb14793d31b3226 | |
| parent | 283b7de6a57ff96db89d46874cfdb6fc590760dc (diff) | |
| download | qemu-27c71355fbf7f999f3fbb8ec42ec88210211b6f4.tar.gz | |
chardev: clear O_NONBLOCK on SCM_RIGHTS file descriptors
When we receive a file descriptor over a UNIX domain socket the
O_NONBLOCK flag is preserved. Clear the O_NONBLOCK flag and rely on
QEMU file descriptor users like migration, SPICE, VNC, block layer, and
others to set non-blocking only when necessary.
This change ensures we don't accidentally expose O_NONBLOCK in the QMP
API. QMP clients should not need to get the non-blocking state
"correct".
A recent real-world example was when libvirt passed a non-blocking TCP
socket for migration where we expected a blocking socket. The source
QEMU produced a corrupted migration stream since its code did not cope
with non-blocking sockets.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry picked from commit e374f7f816171f9783c1d9d00a041f26379f1ac6)
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
| -rw-r--r-- | qemu-char.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/qemu-char.c b/qemu-char.c index 050764b270..f4a74ac26e 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -2252,6 +2252,9 @@ static void unix_process_msgfd(CharDriverState *chr, struct msghdr *msg) if (fd < 0) continue; + /* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */ + qemu_set_block(fd); + #ifndef MSG_CMSG_CLOEXEC qemu_set_cloexec(fd); #endif |