This is a note to let you know that I've just added the patch titled tcp: fix overflow in __tcp_retransmit_skb() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tcp-fix-overflow-in-__tcp_retransmit_skb.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Nov 10 16:42:45 CET 2016 From: Eric Dumazet <edumazet@xxxxxxxxxx> Date: Thu, 15 Sep 2016 08:12:33 -0700 Subject: tcp: fix overflow in __tcp_retransmit_skb() From: Eric Dumazet <edumazet@xxxxxxxxxx> [ Upstream commit ffb4d6c8508657824bcef68a36b2a0f9d8c09d10 ] If a TCP socket gets a large write queue, an overflow can happen in a test in __tcp_retransmit_skb() preventing all retransmits. The flow then stalls and resets after timeouts. Tested: sysctl -w net.core.wmem_max=1000000000 netperf -H dest -- -s 1000000000 Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/tcp_output.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2569,7 +2569,8 @@ int __tcp_retransmit_skb(struct sock *sk * copying overhead: fragmentation, tunneling, mangling etc. */ if (atomic_read(&sk->sk_wmem_alloc) > - min(sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), sk->sk_sndbuf)) + min_t(u32, sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), + sk->sk_sndbuf)) return -EAGAIN; if (skb_still_in_host_queue(sk, skb)) Patches currently in stable-queue which might be from edumazet@xxxxxxxxxx are queue-4.4/ipv4-use-the-right-lock-for-ping_group_range.patch queue-4.4/ipv4-disable-bh-in-set_ping_group_range.patch queue-4.4/tcp-fix-a-compile-error-in-dbgundo.patch queue-4.4/net-avoid-sk_forward_alloc-overflows.patch queue-4.4/udp-fix-ip_checksum-handling.patch queue-4.4/netlink-do-not-enter-direct-reclaim-from-netlink_dump.patch queue-4.4/ipv6-tcp-restore-ip6cb-for-pktoptions-skbs.patch queue-4.4/tcp-fix-overflow-in-__tcp_retransmit_skb.patch queue-4.4/packet-on-direct_xmit-limit-tso-and-csum-to-supported-devices.patch queue-4.4/net-pktgen-remove-rcu-locking-in-pktgen_change_name.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html