summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorHerbert Xu <herbert@gondor.apana.org.au>2005-11-04 09:56:56 +1100
committerArnaldo Carvalho de Melo <acme@mandriva.com>2005-11-05 21:05:20 -0200
commit6151b31c9616d71f714fc7ef8e2306f67f3b94c3 (patch)
tree59ac0ad477d80c53bbf173b5fc863ab239f0705c
parenteb229c4cdc3389682cda20adb015ba767950a220 (diff)
[NET]: Fix race condition in sk_stream_wait_connect
When sk_stream_wait_connect detects a state transition to ESTABLISHED or CLOSE_WAIT prior to it going to sleep, it will return without calling finish_wait and decrementing sk_write_pending. This may result in crashes and other unintended behaviour. The fix is to always call finish_wait and update sk_write_pending since it is safe to do so even if the wait entry is no longer on the queue. This bug was tracked down with the help of Alex Sidorenko and the fix is also based on his suggestion. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
-rw-r--r--net/core/stream.c12
1 files changed, 6 insertions, 6 deletions
diff --git a/net/core/stream.c b/net/core/stream.c
index ac9edfdf874..15bfd03e802 100644
--- a/net/core/stream.c
+++ b/net/core/stream.c
@@ -52,8 +52,9 @@ int sk_stream_wait_connect(struct sock *sk, long *timeo_p)
{
struct task_struct *tsk = current;
DEFINE_WAIT(wait);
+ int done;
- while (1) {
+ do {
if (sk->sk_err)
return sock_error(sk);
if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV))
@@ -65,13 +66,12 @@ int sk_stream_wait_connect(struct sock *sk, long *timeo_p)
prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
sk->sk_write_pending++;
- if (sk_wait_event(sk, timeo_p,
- !((1 << sk->sk_state) &
- ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT))))
- break;
+ done = sk_wait_event(sk, timeo_p,
+ !((1 << sk->sk_state) &
+ ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)));
finish_wait(sk->sk_sleep, &wait);
sk->sk_write_pending--;
- }
+ } while (!done);
return 0;
}