From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Wed, 30 Dec 2015 12:24:17 +0000 (+0800)
Subject: crypto: af_alg - Fix socket double-free when accept fails
X-Git-Tag: v3.2.77~28
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=542b4ad3c5f4cf151306c62ebf4296d4c6bf0fc8

crypto: af_alg - Fix socket double-free when accept fails

commit a383292c86663bbc31ac62cc0c04fc77504636a6 upstream.

When we fail an accept(2) call we will end up freeing the socket
twice, once due to the direct sk_free call and once again through
newsock.

This patch fixes this by removing the sk_free call.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 6ef6e2ad344e..1aaa555fab56 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -247,10 +247,8 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
 	security_sk_clone(sk, sk2);
 
 	err = type->accept(ask->private, sk2);
-	if (err) {
-		sk_free(sk2);
+	if (err)
 		goto unlock;
-	}
 
 	sk2->sk_family = PF_ALG;