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 1AE881C03 for ; Mon, 20 Mar 2023 15:08:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90BBAC433D2; Mon, 20 Mar 2023 15:08:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1679324900; bh=op8VpqsIfPXxl/IrtTBv+laE6kXeoZ+6lLITCFNh7Q8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PBff7GV+q1nvLLdDyRtfc0Dpj0UcM2tJZhoapjf1HQNbFtQixu9igwcQlfTCv+Ou5 W4iVoJhfGJmdl00VG1G6cT+baziWaj72K/mi76eFH6OTo19KLq2dmiUr53IHz4pk2i yMHFnDF97/6RN3z3AFML9yU8taQlWBQXk/ASPWI8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Szymon Heidrich , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 046/115] net: usb: smsc75xx: Move packet length check to prevent kernel panic in skb_pull Date: Mon, 20 Mar 2023 15:54:18 +0100 Message-Id: <20230320145451.354894215@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230320145449.336983711@linuxfoundation.org> References: <20230320145449.336983711@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: Szymon Heidrich [ Upstream commit 43ffe6caccc7a1bb9d7442fbab521efbf6c1378c ] Packet length check needs to be located after size and align_count calculation to prevent kernel panic in skb_pull() in case rx_cmd_a & RX_CMD_A_RED evaluates to true. Fixes: d8b228318935 ("net: usb: smsc75xx: Limit packet length to skb->len") Signed-off-by: Szymon Heidrich Link: https://lore.kernel.org/r/20230316110540.77531-1-szymon.heidrich@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/usb/smsc75xx.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c index 705bd31b18787..7c3e866514199 100644 --- a/drivers/net/usb/smsc75xx.c +++ b/drivers/net/usb/smsc75xx.c @@ -2199,6 +2199,13 @@ static int smsc75xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb) size = (rx_cmd_a & RX_CMD_A_LEN) - RXW_PADDING; align_count = (4 - ((size + RXW_PADDING) % 4)) % 4; + if (unlikely(size > skb->len)) { + netif_dbg(dev, rx_err, dev->net, + "size err rx_cmd_a=0x%08x\n", + rx_cmd_a); + return 0; + } + if (unlikely(rx_cmd_a & RX_CMD_A_RED)) { netif_dbg(dev, rx_err, dev->net, "Error rx_cmd_a=0x%08x\n", rx_cmd_a); @@ -2211,8 +2218,7 @@ static int smsc75xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb) dev->net->stats.rx_frame_errors++; } else { /* MAX_SINGLE_PACKET_SIZE + 4(CRC) + 2(COE) + 4(Vlan) */ - if (unlikely(size > (MAX_SINGLE_PACKET_SIZE + ETH_HLEN + 12) || - size > skb->len)) { + if (unlikely(size > (MAX_SINGLE_PACKET_SIZE + ETH_HLEN + 12))) { netif_dbg(dev, rx_err, dev->net, "size err rx_cmd_a=0x%08x\n", rx_cmd_a); -- 2.39.2