From 9d9b578ffef37278d8c37492c6a0fe75e1f6bab8 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 5 Dec 2019 13:45:05 +0800 Subject: [PATCH] crypto: af_alg - Use bh_lock_sock in sk_destruct commit 37f96694cf73ba116993a9d2d99ad6a75fa7fdb0 upstream. As af_alg_release_parent may be called from BH context (most notably due to an async request that only completes after socket closure, or as reported here because of an RCU-delayed sk_destruct call), we must use bh_lock_sock instead of lock_sock. Reported-by: syzbot+c2f1558d49e25cc36e5e@syzkaller.appspotmail.com Reported-by: Eric Dumazet Fixes: c840ac6af3f8 ("crypto: af_alg - Disallow bind/setkey/...") Cc: Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/af_alg.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/crypto/af_alg.c b/crypto/af_alg.c index 0dceaabc6321..3d8e53010cda 100644 --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -134,11 +134,13 @@ void af_alg_release_parent(struct sock *sk) sk = ask->parent; ask = alg_sk(sk); - lock_sock(sk); + local_bh_disable(); + bh_lock_sock(sk); ask->nokey_refcnt -= nokey; if (!last) last = !--ask->refcnt; - release_sock(sk); + bh_unlock_sock(sk); + local_bh_enable(); if (last) sock_put(sk);