From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 EE6AD3BCD38; Fri, 7 Aug 2026 14:50:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786114222; cv=none; b=c1cGqxtHRAEppEF7t7Jz4nx9Lxg/zedLNQtw9x74qtwF1w9AkbrCCkxBB4GRY740t+CqzW9HLQjX4GqE8uBivFTJJCAutxCvymiez34oQK04djFbs/dvVf9E0iFVxecV5LSMTw1aKNQD1SzQFOzwkPBKN7qhk2Vwr43Rk+B6jOA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786114222; c=relaxed/simple; bh=Axt1L1gwpgBXHa/0k5uLm+g8KZ0k1zc170STF71Wj+c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FppEHAHNQVrQN9kpgrPef8eNGuTyHbA/53xSIeu0q7eAXrUJlksN1JtpcRnR51vb/RHrY2jXp8noKyUqSLoMej8XZx4oAallOMYHmADtQXtT/CLYFFSkjR/lr/NyIvJjBGpiSZdEzRp8uhzsG0gl8mulMktIb2/gEU4hPswoYRE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YqxcRtXh; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="YqxcRtXh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1A9C1F00A3D; Fri, 7 Aug 2026 14:50:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786114218; bh=IOpBmd7f4dsUvoOerfc1CpjnPXPrCAGZmfOzJTqVVJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=YqxcRtXhGKMSDDztIaAR1ZZZwzzUpB12wDBg26PLy8kEGisrZAi3eDozcWCPfJcL5 R4LBvmlAq5+NeFhOUcSkWaKr150HA69pr7tfo0b6pBoOBCVSosDlqiQmo8clayJzpB szTtWrUPiOhIFaW6eK2rQbmeVtVjgSZrT9sMDFEA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Vadim Fedorenko , Jakub Kicinski Subject: [PATCH 6.12 187/337] vxlan: re-fetch eth header after route_shortcircuit() Date: Fri, 7 Aug 2026 16:36:30 +0200 Message-ID: <20260807143422.611149905@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143418.516897842@linuxfoundation.org> References: <20260807143418.516897842@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet commit 1395a676ec15a0a02a2a6d86602324f2d5fd41d5 upstream. Before route_shortcircuit(), the eth header pointer is cached from eth_hdr(skb). Inside route_shortcircuit(), pskb_may_pull() can be called, which may reallocate skb->head. In this case, returning to vxlan_xmit() leaves the cached eth pointer pointing to freed memory, leading to a use-after-free when dereferencing eth->h_dest. Fix this by updating eth = eth_hdr(skb) after calling route_shortcircuit(). Fixes: ae8840825605 ("VXLAN: Allow L2 redirection with L3 switching") Cc: stable@vger.kernel.org Signed-off-by: Eric Dumazet Reviewed-by: Vadim Fedorenko Link: https://patch.msgid.link/20260723144249.759100-2-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/vxlan/vxlan_core.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/net/vxlan/vxlan_core.c +++ b/drivers/net/vxlan/vxlan_core.c @@ -2790,6 +2790,7 @@ static netdev_tx_t vxlan_xmit(struct sk_ (ntohs(eth->h_proto) == ETH_P_IP || ntohs(eth->h_proto) == ETH_P_IPV6)) { did_rsc = route_shortcircuit(dev, skb); + eth = eth_hdr(skb); if (did_rsc) f = vxlan_find_mac_tx(vxlan, eth->h_dest, vni); }