From 24c890dd712f6345e382256cae8c97abb0406b70 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 1 Feb 2024 13:49:09 +0800 Subject: [PATCH] crypto: algif_hash - Remove bogus SGL free on zero-length error path When a zero-length message is hashed by algif_hash, and an error is triggered, it tries to free an SG list that was never allocated in the first place. Fix this by not freeing the SG list on the zero-length error path. Reported-by: Shigeru Yoshida Reported-by: xingwei lee Fixes: b6d972f68983 ("crypto: af_alg/hash: Fix recvmsg() after sendmsg(MSG_MORE)") Cc: Signed-off-by: Herbert Xu Reported-by: syzbot+3266db0c26d1fbbe3abb@syzkaller.appspotmail.com Signed-off-by: Herbert Xu --- crypto/algif_hash.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c index 82c44d4899b9..e24c829d7a01 100644 --- a/crypto/algif_hash.c +++ b/crypto/algif_hash.c @@ -91,13 +91,13 @@ static int hash_sendmsg(struct socket *sock, struct msghdr *msg, if (!(msg->msg_flags & MSG_MORE)) { err = hash_alloc_result(sk, ctx); if (err) - goto unlock_free; + goto unlock_free_result; ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0); err = crypto_wait_req(crypto_ahash_final(&ctx->req), &ctx->wait); if (err) - goto unlock_free; + goto unlock_free_result; } goto done_more; } @@ -170,6 +170,7 @@ unlock: unlock_free: af_alg_free_sg(&ctx->sgl); +unlock_free_result: hash_free_result(sk, ctx); ctx->more = false; goto unlock;