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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A8333C4451C for ; Wed, 22 Jul 2026 03:34:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=UyfeTtjC2ZIxhQHTBzzT24VyhmFbnqE24bjSAL7D0M0=; b=LxP5cfEW0Py2ITy+wNHEbuxGKh ARY48L726EmJYqAu+8B6Juu6nHkQCzbSOmhqe3WZF9Bsg6tXr/p90RN0ybGxp3yak+9Jpc1rKAzBa mHGzrsOXd8Sds9vxtWnT9JO0mYhr1HUfU7v+G/QDbJgilAA7yCm0vBS5NTUd3kjEpoOgpIWrQewvR K+/QRIKfSPLuKjAXzrgtV4Yo/FvG6nMV7aJ/R8qOrmnvVWPBPjbpg5KJMgJ4tQpuv5gb1jZQi2ZXk Sr7/0RTNs12mTicZXWVVqN2/hH515i7IFUKkCy4V7b+L9iW2qE5r5MGFq9ETfNLkbK06qZ0VhI7AP RQE70bow==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmMup-0000000AmRo-3FvS; Wed, 22 Jul 2026 02:42:35 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmMum-0000000AmRJ-4AEr; Wed, 22 Jul 2026 02:42:34 +0000 X-UUID: f91418fe857611f1acbe4559397dec65-20260721 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=UyfeTtjC2ZIxhQHTBzzT24VyhmFbnqE24bjSAL7D0M0=; b=uRE3I9s73UtNQnCH1Ggdc+jPjkpYkIOObCZOurF9JQLFsUnwLBO/LFeQcJ/5O7RUW6ig6Cbq3AxjcVLAmk5FsQcfaqFOT6WK4dGuOB1/8YvQV6kH+c9sOVcukNTH8wZMqjA/ZOWw249kU2bnA5aio+a6KuA624e8WgqxorW+dIg=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.18,REQID:dd320a5b-582a-4445-988f-5bc0418c1ad2,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:8a735a6,CLOUDID:976f8d3f-46cf-453a-bd84-ad9fc7cb0e8c,B ulkID:nil,BulkQuantity:0,SF:102|123|836|865|888|898,TC:-5,Content:0|15|50| 99|100|101|123,EDM:-3,IP:nil,URL:0,File:130,RT:0,Bulk:nil,QS:nil,BEC:-1,CO L:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: f91418fe857611f1acbe4559397dec65-20260721 Received: from mtkmbs14n1.mediatek.inc [(172.21.101.75)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1565529495; Tue, 21 Jul 2026 19:42:25 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs13n1.mediatek.inc (172.21.101.193) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.29; Wed, 22 Jul 2026 10:42:23 +0800 Received: from mcddlt001.gcn.mediatek.inc (10.19.240.15) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.2562.29 via Frontend Transport; Wed, 22 Jul 2026 10:42:21 +0800 From: To: , , , , , , , , , , , , , , , , , , CC: , , , Zhaoping Shu Subject: [PATCH net v1] net: gro: avoid nesting GSO skbs in skb_gro_receive_list() Date: Wed, 22 Jul 2026 10:42:14 +0800 Message-ID: <20260722024214.24845-1-zhaoping.shu@mediatek.com> X-Mailer: git-send-email 2.17.0 MIME-Version: 1.0 Content-Type: text/plain X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260721_194233_097540_CE3C023B X-CRM114-Status: GOOD ( 15.27 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: HW He On devices that support both NETIF_F_GRO_HW and NETIF_F_GRO_FRAGLIST, the hardware or driver may deliver packets that have already been aggregated into a GSO skb, either with frags[] or frag_list. GRO may then aggregate the skb again in skb_gro_receive_list(). This can create a nested GSO skb, which is not handled correctly by the later GSO segmentation paths. When the skb is segmented by skb_segment_list(), it not be fully restored to the original packets. If the skb is marked with SKB_GSO_DODGY before segmentation, for example after a protocol change from IPv6 to IPv4, the nested GSO skb is segmented by skb_segment(), which may hit a NULL pointer dereference when the skb contains a nested frag_list. Avoid this by setting NAPI_GRO_CB(skb)->flush for GSO skbs before aggregation and by checking the flush flag in skb_gro_receive_list(), following the existing logic in skb_gro_receive(). Signed-off-by: HW He Signed-off-by: Zhaoping Shu --- net/core/gro.c | 2 +- net/ipv4/tcp_offload.c | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/net/core/gro.c b/net/core/gro.c index 35f2f708f010..27c9813495f3 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -229,7 +229,7 @@ int skb_gro_receive(struct sk_buff *p, struct sk_buff *skb) int skb_gro_receive_list(struct sk_buff *p, struct sk_buff *skb) { - if (unlikely(p->len + skb->len >= 65536)) + if (unlikely(p->len + skb->len >= 65536 || NAPI_GRO_CB(skb)->flush)) return -E2BIG; if (!pskb_may_pull(skb, skb_gro_offset(skb))) { diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index 3b1fdcd3cb29..c363434a5646 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -332,6 +332,7 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb, flush |= skb->ip_summed != p->ip_summed; flush |= skb->csum_level != p->csum_level; flush |= NAPI_GRO_CB(p)->count >= 64; + NAPI_GRO_CB(skb)->flush |= skb_is_gso(skb); skb_set_network_header(skb, skb_gro_receive_network_offset(skb)); if (flush || skb_gro_receive_list(p, skb)) -- 2.17.0