From: Paolo Abeni pabeni@redhat.com
[ Upstream commit d39ca2590d10712f412add7a88e1dd467a7246f4 ]
This reverts commit 0d4a6608f68c7532dcbfec2ea1150c9761767d03.
Willem reported that after commit 0d4a6608f68c ("udp: do rmem bulk free even if the rx sk queue is empty") the memory allocated by an almost idle system with many UDP sockets can grow a lot.
For stable kernel keep the solution as simple as possible and revert the offending commit.
Reported-by: Willem de Bruijn willemdebruijn.kernel@gmail.com Diagnosed-by: Eric Dumazet eric.dumazet@gmail.com Fixes: 0d4a6608f68c ("udp: do rmem bulk free even if the rx sk queue is empty") Signed-off-by: Paolo Abeni pabeni@redhat.com Acked-by: Willem de Bruijn willemb@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/udp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1305,7 +1305,8 @@ static void udp_rmem_release(struct sock if (likely(partial)) { up->forward_deficit += size; size = up->forward_deficit; - if (size < (sk->sk_rcvbuf >> 2)) + if (size < (sk->sk_rcvbuf >> 2) && + !skb_queue_empty(&up->reader_queue)) return; } else { size += up->forward_deficit;