crypto: algif_hash - Remove bogus SGL free on zero-length error path

commit 24c890dd71 upstream.

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 <syoshida@redhat.com>
Reported-by: xingwei lee <xrivendell7@gmail.com>
Fixes: b6d972f689 ("crypto: af_alg/hash: Fix recvmsg() after sendmsg(MSG_MORE)")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: syzbot+3266db0c26d1fbbe3abb@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Herbert Xu 2024-02-01 13:49:09 +08:00 committed by Greg Kroah-Hartman
parent b5909f197f
commit 775f3c1882

View file

@ -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 @@ static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
unlock_free:
af_alg_free_sg(&ctx->sgl);
unlock_free_result:
hash_free_result(sk, ctx);
ctx->more = false;
goto unlock;