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 EB3E611C86 for ; Thu, 24 Aug 2023 14:52:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B8ECC433CD; Thu, 24 Aug 2023 14:52:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1692888749; bh=9BgpmCh2TK37oz++8FSQEYQRTmmRj4XvsahykOaevLg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RoaVIMVcaNTXMTo11ngGE9tBsMKV+sQ2Fm9GI+KIhwN/Km6TC1YyIj4Zifxszyj9Z LvOhwCLsxW0xPuBCrYKK10fxQDAsoOHIGSa1FKe6jN90owR6yfhr08meoYHTNLX4Sa wADSW6jXj9U8Y+61KjuLDCc+/Ez6sowjnX3kl4Dk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhang Shurong , Takashi Sakamoto , Sasha Levin Subject: [PATCH 5.15 028/139] firewire: net: fix use after free in fwnet_finish_incoming_packet() Date: Thu, 24 Aug 2023 16:49:11 +0200 Message-ID: <20230824145024.809784960@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230824145023.559380953@linuxfoundation.org> References: <20230824145023.559380953@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Zhang Shurong [ Upstream commit 3ff256751a2853e1ffaa36958ff933ccc98c6cb5 ] The netif_rx() function frees the skb so we can't dereference it to save the skb->len. Signed-off-by: Zhang Shurong Link: https://lore.kernel.org/r/tencent_3B3D24B66ED66A6BB73CC0E63C6A14E45109@qq.com Signed-off-by: Takashi Sakamoto Signed-off-by: Sasha Levin --- drivers/firewire/net.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/firewire/net.c b/drivers/firewire/net.c index 4c3fd2eed1da4..beba0a56bb9ae 100644 --- a/drivers/firewire/net.c +++ b/drivers/firewire/net.c @@ -488,7 +488,7 @@ static int fwnet_finish_incoming_packet(struct net_device *net, struct sk_buff *skb, u16 source_node_id, bool is_broadcast, u16 ether_type) { - int status; + int status, len; switch (ether_type) { case ETH_P_ARP: @@ -542,13 +542,15 @@ static int fwnet_finish_incoming_packet(struct net_device *net, } skb->protocol = protocol; } + + len = skb->len; status = netif_rx(skb); if (status == NET_RX_DROP) { net->stats.rx_errors++; net->stats.rx_dropped++; } else { net->stats.rx_packets++; - net->stats.rx_bytes += skb->len; + net->stats.rx_bytes += len; } return 0; -- 2.40.1