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 36C102F39C2; Wed, 8 Apr 2026 18:37:24 +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=1775673444; cv=none; b=QGNny6xycA1WE455euPu01hp6mfWiTGyjeD4sm0HO4ncVdQvszUBvCXgxBiRFnBBbPC2W/8eRw0pJP/MHK/FoWdpjqD2AYCU3QxLXMylVN/ESraW//OyTOWHc9dDsBYlewknxIVYaAYSYuhA166D12iiOVg3dbKZ9TnHukPszYg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775673444; c=relaxed/simple; bh=FoWHVLifwhPWRMCDgYFQH/Yz7AwjL9Vh6cAMEBY04yk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IeR7Te/zpeo99ZXCoW4x3G7t4bRqHvTAP72fZQCIyzxaJjK+qB8bM4N4xQ7pB5dp9EeL+j2mu6Fedoyq5W5OsokyG+4q3hYWGelqlIg/qvcmMbmLLGYH51wQmBrU+Lfq91rw94VAEcyORKc1/ZpXnH4v/EdFlTvN6I3KsoM/wrM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=b2mDLYn0; 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="b2mDLYn0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C2FA7C2BC87; Wed, 8 Apr 2026 18:37:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775673444; bh=FoWHVLifwhPWRMCDgYFQH/Yz7AwjL9Vh6cAMEBY04yk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b2mDLYn0tdEhwGUM1bt9vouJ/05wqB0kTcDWk/tsi87+Ry6XThei8XGmQMMUz+A4z xx64V08aHwjtd69n4NmBiwSQq+efL2KdEIiv7uzwLWmYwWQDQpxR/X463XukAGIBNb tNDgPl3Pkp1tOrF3Q6LOGcJaDRcFa++IkfKx79xc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Sven Eckelmann (Plasma Cloud)" , Simon Horman , Jakub Kicinski Subject: [PATCH 6.18 234/277] net: ethernet: mtk_ppe: avoid NULL deref when gmac0 is disabled Date: Wed, 8 Apr 2026 20:03:39 +0200 Message-ID: <20260408175942.596244999@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175933.836769063@linuxfoundation.org> References: <20260408175933.836769063@linuxfoundation.org> User-Agent: quilt/0.69 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-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann (Plasma Cloud) commit 976ff48c2ac6e6b25b01428c9d7997bcd0fb2949 upstream. If the gmac0 is disabled, the precheck for a valid ingress device will cause a NULL pointer deref and crash the system. This happens because eth->netdev[0] will be NULL but the code will directly try to access netdev_ops. Instead of just checking for the first net_device, it must be checked if any of the mtk_eth net_devices is matching the netdev_ops of the ingress device. Cc: stable@vger.kernel.org Fixes: 73cfd947dbdb ("net: ethernet: mtk_eth_soc: ppe: prevent ppe update for non-mtk devices") Signed-off-by: Sven Eckelmann (Plasma Cloud) Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260324-wed-crash-gmac0-disabled-v1-1-3bc388aee565@simonwunderlich.de Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mediatek/mtk_ppe_offload.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c +++ b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c @@ -244,6 +244,25 @@ out: return 0; } +static bool +mtk_flow_is_valid_idev(const struct mtk_eth *eth, const struct net_device *idev) +{ + size_t i; + + if (!idev) + return false; + + for (i = 0; i < ARRAY_SIZE(eth->netdev); i++) { + if (!eth->netdev[i]) + continue; + + if (idev->netdev_ops == eth->netdev[i]->netdev_ops) + return true; + } + + return false; +} + static int mtk_flow_offload_replace(struct mtk_eth *eth, struct flow_cls_offload *f, int ppe_index) @@ -270,7 +289,7 @@ mtk_flow_offload_replace(struct mtk_eth flow_rule_match_meta(rule, &match); if (mtk_is_netsys_v2_or_greater(eth)) { idev = __dev_get_by_index(&init_net, match.key->ingress_ifindex); - if (idev && idev->netdev_ops == eth->netdev[0]->netdev_ops) { + if (mtk_flow_is_valid_idev(eth, idev)) { struct mtk_mac *mac = netdev_priv(idev); if (WARN_ON(mac->ppe_idx >= eth->soc->ppe_num))