From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E5BDC433B4 for ; Wed, 5 May 2021 16:34:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 360216141C for ; Wed, 5 May 2021 16:34:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234468AbhEEQez (ORCPT ); Wed, 5 May 2021 12:34:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:53688 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234226AbhEEQdL (ORCPT ); Wed, 5 May 2021 12:33:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 69F9B613EB; Wed, 5 May 2021 16:32:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620232333; bh=DOfZvo4CKUnUhyiFQqb2bJV2N7uJhWIYyvNwVyHWo/w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MvpL//05kkJIBJBPzzzccuxGxidp8I1JiF/6AkqfWfABfjHP7Z6oigk9zswCjXwUY 39TMX5HE4YsvStQZQvkO7pDhOVAGZ5+Pr1lNsM9EdEJPkPdnFU4OBUiV+QnhzVhewf Bfvgz5fuEOQ5oAZtkCxcetWRwyaVIPV1m2fH0oV/etzwTuAcTdoUwes68i46xyLP5q 4+uTMv+pufsb0/PAHAHyDaiUKU0kGjCWcbumP+FxaApT03rW3AJxCMyrvziuu2adyi XClBM2vJwSLkeVkZfs9hBFhoZzTCdrNrGU7RmchUkUuuqF7Pf33Q/wvBRAapBk0+Sw 39y2UP3hrm5FA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Marc Kleine-Budde , Sasha Levin , linux-can@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.12 035/116] can: dev: can_free_echo_skb(): don't crash the kernel if can_priv::echo_skb is accessed out of bounds Date: Wed, 5 May 2021 12:30:03 -0400 Message-Id: <20210505163125.3460440-35-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210505163125.3460440-1-sashal@kernel.org> References: <20210505163125.3460440-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marc Kleine-Budde [ Upstream commit 4168d079aa41498639b2c64b4583375bcdf360d9 ] A out of bounds access to "struct can_priv::echo_skb" leads to a kernel crash. Better print a sensible warning message instead and try to recover. This patch is similar to: | e7a6994d043a ("can: dev: __can_get_echo_skb(): Don't crash the kernel | if can_priv::echo_skb is accessed out of bounds") Link: https://lore.kernel.org/r/20210319142700.305648-2-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin --- drivers/net/can/dev/skb.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index 6a64fe410987..c3508109263e 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -151,7 +151,11 @@ void can_free_echo_skb(struct net_device *dev, unsigned int idx) { struct can_priv *priv = netdev_priv(dev); - BUG_ON(idx >= priv->echo_skb_max); + if (idx >= priv->echo_skb_max) { + netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", + __func__, idx, priv->echo_skb_max); + return; + } if (priv->echo_skb[idx]) { dev_kfree_skb_any(priv->echo_skb[idx]); -- 2.30.2