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| author | dann frazier <dannf@hp.com> | 2008-11-26 15:32:27 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-12-05 10:55:25 -0800 |
| commit | d7fc504d906a210ae3e24741e45504c1df87035f (patch) | |
| tree | 1cc76cf229b4ed278b4443bd6aaf99ede5e6c396 /net/unix/af_unix.c | |
| parent | 3d772f32ee07cf4e8af29539786153d83858f809 (diff) | |
| download | lwn-d7fc504d906a210ae3e24741e45504c1df87035f.tar.gz lwn-d7fc504d906a210ae3e24741e45504c1df87035f.zip | |
net: Fix soft lockups/OOM issues w/ unix garbage collector (CVE-2008-5300)
commit 5f23b734963ec7eaa3ebcd9050da0c9b7d143dd3 upstream.
This is an implementation of David Miller's suggested fix in:
https://bugzilla.redhat.com/show_bug.cgi?id=470201
It has been updated to use wait_event() instead of
wait_event_interruptible().
Paraphrasing the description from the above report, it makes sendmsg()
block while UNIX garbage collection is in progress. This avoids a
situation where child processes continue to queue new FDs over a
AF_UNIX socket to a parent which is in the exit path and running
garbage collection on these FDs. This contention can result in soft
lockups and oom-killing of unrelated processes.
Signed-off-by: dann frazier <dannf@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'net/unix/af_unix.c')
| -rw-r--r-- | net/unix/af_unix.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 8bde9bf88138..b0785ef0a475 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -1341,6 +1341,7 @@ static int unix_dgram_sendmsg(struct kiocb *kiocb, struct socket *sock, if (NULL == siocb->scm) siocb->scm = &tmp_scm; + wait_for_unix_gc(); err = scm_send(sock, msg, siocb->scm); if (err < 0) return err; @@ -1491,6 +1492,7 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock, if (NULL == siocb->scm) siocb->scm = &tmp_scm; + wait_for_unix_gc(); err = scm_send(sock, msg, siocb->scm); if (err < 0) return err; |