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 2217930BF6F; Mon, 13 Apr 2026 16:22:37 +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=1776097358; cv=none; b=Q8daWB1eMo58c1iIkkYFA/+TdVNnsSYEKIKYKYnU+CyuS36Ge8uJHkz7sykmgbiC5X/oUiRPFeG9BOUjZhMxTRM+ynS7nnwry8KrLEq10PW6h3D7oU9LeecoqUhXjJIt6T+L68ghX7ET7HEIOqbhTM6nRNjsxgc7VhIlqARzdE4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776097358; c=relaxed/simple; bh=/QEfqMsJDfxm3yiSRd1MSaC8MZPMJZ3VtqHprplqv1E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BuBu7dQIkfcRvw647R2a0lOq1qj3VMkOlxfUrgatX6MoIwKN/M/WjJ7agoJdwZFilWedr7NJzC1qNhJz9lsTuyAfYPjDoHV6uUI4jKSPjEsFFR8s/ykkWLb9PcfMEToHGT5MtrBFBAtjVep3XOE0b1MqbJuwOU7PhY1lYRJ9ylA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2T0gWdCR; 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="2T0gWdCR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68855C2BCAF; Mon, 13 Apr 2026 16:22:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776097357; bh=/QEfqMsJDfxm3yiSRd1MSaC8MZPMJZ3VtqHprplqv1E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2T0gWdCRC9WcxSSDZJ1ty0POJOg6BA705LDGtc8JkQskzFjmMI7Lkh2GWKSkQN7Sa aPob28oRcHfdM//E5o9fYvKEskjVk2IUJ41a4uz544/v4C9TBHW6qBW56UoGczb6nl MRkwhfOjlRpgGn6PV/PBVgVxcGvKrg2azspy424w= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xiang Mei , Weiming Shi , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 105/570] net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit Date: Mon, 13 Apr 2026 17:53:56 +0200 Message-ID: <20260413155834.376845478@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260413155830.386096114@linuxfoundation.org> References: <20260413155830.386096114@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Weiming Shi [ Upstream commit 0cc0c2e661af418bbf7074179ea5cfffc0a5c466 ] teql_master_xmit() calls netdev_start_xmit(skb, slave) to transmit through slave devices, but does not update skb->dev to the slave device beforehand. When a gretap tunnel is a TEQL slave, the transmit path reaches iptunnel_xmit() which saves dev = skb->dev (still pointing to teql0 master) and later calls iptunnel_xmit_stats(dev, pkt_len). This function does: get_cpu_ptr(dev->tstats) Since teql_master_setup() does not set dev->pcpu_stat_type to NETDEV_PCPU_STAT_TSTATS, the core network stack never allocates tstats for teql0, so dev->tstats is NULL. get_cpu_ptr(NULL) computes NULL + __per_cpu_offset[cpu], resulting in a page fault. BUG: unable to handle page fault for address: ffff8880e6659018 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 68bc067 P4D 68bc067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN PTI RIP: 0010:iptunnel_xmit (./include/net/ip_tunnels.h:664 net/ipv4/ip_tunnel_core.c:89) Call Trace: ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847) __gre_xmit (net/ipv4/ip_gre.c:478) gre_tap_xmit (net/ipv4/ip_gre.c:779) teql_master_xmit (net/sched/sch_teql.c:319) dev_hard_start_xmit (net/core/dev.c:3887) sch_direct_xmit (net/sched/sch_generic.c:347) __dev_queue_xmit (net/core/dev.c:4802) neigh_direct_output (net/core/neighbour.c:1660) ip_finish_output2 (net/ipv4/ip_output.c:237) __ip_finish_output.part.0 (net/ipv4/ip_output.c:315) ip_mc_output (net/ipv4/ip_output.c:369) ip_send_skb (net/ipv4/ip_output.c:1508) udp_send_skb (net/ipv4/udp.c:1195) udp_sendmsg (net/ipv4/udp.c:1485) inet_sendmsg (net/ipv4/af_inet.c:859) __sys_sendto (net/socket.c:2206) Fix this by setting skb->dev = slave before calling netdev_start_xmit(), so that tunnel xmit functions see the correct slave device with properly allocated tstats. Fixes: 039f50629b7f ("ip_tunnel: Move stats update to iptunnel_xmit()") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Link: https://patch.msgid.link/20260304044216.3517851-3-bestswngs@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_teql.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/sched/sch_teql.c b/net/sched/sch_teql.c index e9dfa140799c3..4c65b4ed5ccd3 100644 --- a/net/sched/sch_teql.c +++ b/net/sched/sch_teql.c @@ -315,6 +315,7 @@ static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev) if (__netif_tx_trylock(slave_txq)) { unsigned int length = qdisc_pkt_len(skb); + skb->dev = slave; if (!netif_xmit_frozen_or_stopped(slave_txq) && netdev_start_xmit(skb, slave, slave_txq, false) == NETDEV_TX_OK) { -- 2.51.0