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 99C6E4E9C14; Fri, 9 Oct 2026 14:44:38 +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=1791557079; cv=none; b=UAsnn9lijuviy01r5plp78rBJKpajC0ARGm+h4bJ6RTQiFt4xMVwC3p8tzKeaYfy6YgoPTRLPaqS7xWrZ6OIL7FvAyg+wlA74QsnmP2K0qSo0vQikcKpDxE0dEhQDcQfDnWIs+Jr+HHKD0LSN2tyZIhqbrMBQon8haKEWBWO0vA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791557079; c=relaxed/simple; bh=pQH70aXqNVgix5RSew4ELqiGz2E8KeAEKm+aUcGPcdg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dMFj7J28OIpgSl4c3no47gtceLmUh0Y0qndfUEcuPnwPWJoGLJ2BtymXeHzin/49WGx8r6PTZdo3RwyMSIqhBd6Vuj9nyDc3Fcs0xG2eb4O8NXK8ddXOPic282MZbjHKVkeHLc1+DKShtAlJNbstz/4u9nOCQwAQG0X1Pf52QQE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=fEIah/JQ; 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="fEIah/JQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF5DB1F000FF; Fri, 9 Oct 2026 14:44:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791557078; bh=0N/czZAAOFB0ZhzOUot7P6PlGiQX+0s4BhtlEDmQnMo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=fEIah/JQg9UD1Zw18pPGqDWaEGjSwYQu5zLVJn/LiJjaCn/3m6jekEvWI/CGmzgsv kYly/9siXU1quyYg+82xUjbd5ISkfUKGVjFvRA6A+InswF1fuUkGGboiEHlvKuH0db pBR1+UwpidqZQ1Bif1N2UfxjmUQuC0gAT1Az0+RA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xuanqiang Luo , Simon Horman , Paolo Abeni , Sasha Levin Subject: [PATCH 6.18 343/403] pfcp: fix socket lifetime on netdevice registration failure Date: Fri, 9 Oct 2026 16:11:44 +0200 Message-ID: <20261009141000.287134369@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261009140952.119038291@linuxfoundation.org> References: <20261009140952.119038291@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xuanqiang Luo [ Upstream commit 0f17d2e3dd9cda3ee6d94033d5e5489af168920d ] pfcp_newlink() creates the UDP socket before register_netdevice(). If registration fails after pfcp_dev_init() succeeds, the core calls pfcp_dev_uninit(), which releases the socket and clears pfcp->sk. The newlink error path then releases it again, causing a NULL pointer dereference. This was observed with failslab fault injection: FAULT_INJECTION: forcing a failure. kobject: kobject_add_internal failed for pfcp0 (error: -12 parent: net) BUG: KASAN: null-ptr-deref in udp_tunnel_sock_release+0x1c/0x50 Read of size 8 at addr 0000000000000120 by task ip/1037 Call trace: show_stack+0x18/0x24 (C) dump_stack_lvl+0x78/0x90 print_report+0x468/0x5cc kasan_report+0xa4/0xf0 __asan_load8+0x7c/0xd0 udp_tunnel_sock_release+0x1c/0x50 pfcp_newlink+0x128/0x184 rtnl_newlink+0x848/0xe44 rtnetlink_rcv_msg+0x468/0x514 netlink_rcv_skb+0xc0/0x1f0 rtnetlink_rcv+0x18/0x24 netlink_unicast+0x4b8/0x558 netlink_sendmsg+0x2b8/0x584 ... Return from pfcp_del_sock() if pfcp->sk is NULL. Fixes: 76c8764ef36a5 ("pfcp: add PFCP module") Cc: stable@vger.kernel.org Signed-off-by: Xuanqiang Luo Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260924055252.33488-1-xuanqiang.luo@linux.dev Signed-off-by: Paolo Abeni [ sashal: Changed the NULL check from pfcp->sk to pfcp->sock. ] Signed-off-by: Sasha Levin --- drivers/net/pfcp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/pfcp.c b/drivers/net/pfcp.c index a6aa30ae0af76..c1c8eaea63fc3 100644 --- a/drivers/net/pfcp.c +++ b/drivers/net/pfcp.c @@ -104,6 +104,9 @@ static int pfcp_encap_recv(struct sock *sk, struct sk_buff *skb) static void pfcp_del_sock(struct pfcp_dev *pfcp) { + if (!pfcp->sock) + return; + udp_tunnel_sock_release(pfcp->sock); pfcp->sock = NULL; } -- 2.53.0