The commit is pushed to "branch-rh7-3.10.0-514.6.1.vz7.28.x-ovz" and will
appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-514.6.1.vz7.28.7
------>
commit b207397b05680d0d47b484ff3090194eb10f5cc8
Author: Eric Dumazet <eduma...@google.com>
Date: Fri Feb 3 14:59:38 2017 -0800
ms/tcp: avoid infinite loop in tcp_splice_read()
Splicing from TCP socket is vulnerable when a packet with URG flag is
received and stored into receive queue.
__tcp_splice_read() returns 0, and sk_wait_data() immediately
returns since there is the problematic skb in queue.
This is a nice way to burn cpu (aka infinite loop) and trigger
soft lockups.
Again, this gem was found by syzkaller tool.
Fixes: 9c55e01c0cc8 ("[TCP]: Splice receive support.")
Signed-off-by: Eric Dumazet <eduma...@google.com>
Reported-by: Dmitry Vyukov <dvyu...@google.com>
Cc: Willy Tarreau <w...@1wt.eu>
Signed-off-by: David S. Miller <da...@davemloft.net>
https://jira.sw.ru/browse/PSBM-61135
https://bugzilla.redhat.com/show_bug.cgi?id=1426542
CVE-2017-6214 kernel: ipv4/tcp: Infinite loop in tcp_splice_read()
(cherry picked from commit ccf7abb93af09ad0868ae9033d1ca8108bdaec82)
Signed-off-by: Konstantin Khorenko <khore...@virtuozzo.com>
---
net/ipv4/tcp.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 277e3d2..1f7df79 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -768,6 +768,12 @@ ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos,
ret = -EAGAIN;
break;
}
+ /* if __tcp_splice_read() got nothing while we have
+ * an skb in receive queue, we do not want to loop.
+ * This might happen with URG data.
+ */
+ if (!skb_queue_empty(&sk->sk_receive_queue))
+ break;
sk_wait_data(sk, &timeo, NULL);
if (signal_pending(current)) {
ret = sock_intr_errno(timeo);
_______________________________________________
Devel mailing list
Devel@openvz.org
https://lists.openvz.org/mailman/listinfo/devel
