From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E865013AA4C; Tue, 27 Feb 2024 13:42:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709041375; cv=none; b=AJr7viodNnu/NQjqFxcEm4AXH+bHzFKaCbPJsuNXzSPh5dGLI9OwSwER+GbAbvB+sJvzPgo6YDXWepiQONOLxjNUi7xtaO3E9IY+RrAquI9yooQVJczByWSbN71xSWSThZCeZMKso3ohuF8mjv9ej7ZoNGXSeq+cwZxGfCLPccI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709041375; c=relaxed/simple; bh=pQ+sh3a0csUHp1ZVIw7rRam+w7apIvYu2o/jbjnvZjo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=UY2FD3DFaphTEbXnLcPos1cwzofgj1JkCLbKK3PTPx5f33pP0tESOasCTN58OKfGGG487KkqZJ5gikwxvAJbM+euTHAlqv2NLrgX8sze68V3NsaBl2TtuYLs0mwBSBfcve74kwRZHUlMbEqsFwzp6QOlf79+DtDKxcwXXYbBAdY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uyrMozSa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="uyrMozSa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 772EFC433F1; Tue, 27 Feb 2024 13:42:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709041374; bh=pQ+sh3a0csUHp1ZVIw7rRam+w7apIvYu2o/jbjnvZjo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uyrMozSaT6rfY4PWbz0Ch57XMPHBP+UagxwOxRqgykDgG6h0KA3ql+nD9geDzxLp7 el//W9oEFtcacJef+7p4/4JG5g0PJ29TCAEJUqmJr8tl862UMSkZAyH+4438LshfPz LjU8dMmvBOweOvQU6ORwYdfN6wqg9k9bSq62l6do= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= , Paolo Abeni , Sasha Levin Subject: [PATCH 6.7 318/334] phonet/pep: fix racy skb_queue_empty() use Date: Tue, 27 Feb 2024 14:22:56 +0100 Message-ID: <20240227131641.356956716@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240227131630.636392135@linuxfoundation.org> References: <20240227131630.636392135@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rémi Denis-Courmont [ Upstream commit 7d2a894d7f487dcb894df023e9d3014cf5b93fe5 ] The receive queues are protected by their respective spin-lock, not the socket lock. This could lead to skb_peek() unexpectedly returning NULL or a pointer to an already dequeued socket buffer. Fixes: 9641458d3ec4 ("Phonet: Pipe End Point for Phonet Pipes protocol") Signed-off-by: Rémi Denis-Courmont Link: https://lore.kernel.org/r/20240218081214.4806-2-remi@remlab.net Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/phonet/pep.c | 41 ++++++++++++++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 9 deletions(-) diff --git a/net/phonet/pep.c b/net/phonet/pep.c index faba31f2eff29..3dd5f52bc1b58 100644 --- a/net/phonet/pep.c +++ b/net/phonet/pep.c @@ -917,6 +917,37 @@ static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len) return 0; } +static unsigned int pep_first_packet_length(struct sock *sk) +{ + struct pep_sock *pn = pep_sk(sk); + struct sk_buff_head *q; + struct sk_buff *skb; + unsigned int len = 0; + bool found = false; + + if (sock_flag(sk, SOCK_URGINLINE)) { + q = &pn->ctrlreq_queue; + spin_lock_bh(&q->lock); + skb = skb_peek(q); + if (skb) { + len = skb->len; + found = true; + } + spin_unlock_bh(&q->lock); + } + + if (likely(!found)) { + q = &sk->sk_receive_queue; + spin_lock_bh(&q->lock); + skb = skb_peek(q); + if (skb) + len = skb->len; + spin_unlock_bh(&q->lock); + } + + return len; +} + static int pep_ioctl(struct sock *sk, int cmd, int *karg) { struct pep_sock *pn = pep_sk(sk); @@ -929,15 +960,7 @@ static int pep_ioctl(struct sock *sk, int cmd, int *karg) break; } - lock_sock(sk); - if (sock_flag(sk, SOCK_URGINLINE) && - !skb_queue_empty(&pn->ctrlreq_queue)) - *karg = skb_peek(&pn->ctrlreq_queue)->len; - else if (!skb_queue_empty(&sk->sk_receive_queue)) - *karg = skb_peek(&sk->sk_receive_queue)->len; - else - *karg = 0; - release_sock(sk); + *karg = pep_first_packet_length(sk); ret = 0; break; -- 2.43.0