From: Eric Dumazet edumazet@google.com
commit c4ee118561a0f74442439b7b5b486db1ac1ddfeb upstream.
sk_forced_mem_schedule() has a bug similar to ones fixed in commit 7c80b038d23e ("net: fix sk_wmem_schedule() and sk_rmem_schedule() errors")
While this bug has little chance to trigger in old kernels, we need to fix it before the following patch.
Fixes: d83769a580f1 ("tcp: fix possible deadlock in tcp_send_fin()") Signed-off-by: Eric Dumazet edumazet@google.com Acked-by: Soheil Hassas Yeganeh soheil@google.com Reviewed-by: Shakeel Butt shakeelb@google.com Reviewed-by: Wei Wang weiwan@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/tcp_output.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
--- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3086,11 +3086,12 @@ void tcp_xmit_retransmit_queue(struct so */ void sk_forced_mem_schedule(struct sock *sk, int size) { - int amt; + int delta, amt;
- if (size <= sk->sk_forward_alloc) + delta = size - sk->sk_forward_alloc; + if (delta <= 0) return; - amt = sk_mem_pages(size); + amt = sk_mem_pages(delta); sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; sk_memory_allocated_add(sk, amt);