From 820ed3fb2e6e986144465082d041e6a403a94135 Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Mon, 2 Apr 2018 12:50:46 -0700 Subject: [PATCH] bpf: sockmap, free memory on sock close with cork data If a socket with pending cork data is closed we do not return the memory to the socket until the garbage collector free's the psock structure. The garbage collector though can run after the sock has completed its close operation. If this ordering happens the sock code will through a WARN_ON because there is still outstanding memory accounted to the sock. To resolve this ensure we return memory to the sock when a socket is closed. Signed-off-by: John Fastabend Fixes: 91843d540a13 ("bpf: sockmap, add msg_cork_bytes() helper") Signed-off-by: Daniel Borkmann --- kernel/bpf/sockmap.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index d2bda5aa25d7..8ddf326b3ade 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -211,6 +211,12 @@ static void bpf_tcp_close(struct sock *sk, long timeout) close_fun = psock->save_close; write_lock_bh(&sk->sk_callback_lock); + if (psock->cork) { + free_start_sg(psock->sock, psock->cork); + kfree(psock->cork); + psock->cork = NULL; + } + list_for_each_entry_safe(md, mtmp, &psock->ingress, list) { list_del(&md->list); free_start_sg(psock->sock, md); -- 2.20.1