From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-vs2-f43.google.com (mail-vs2-f43.google.com [74.125.227.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6172F326D4A for ; Mon, 28 Sep 2026 03:58:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.227.43 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790567884; cv=none; b=d/AyBntSm8LzY5KHRWQZGlvRqdFJe7Xrr9oJOGheHdR6vk9DmVg0WfarVahs1D/8lSboSFkcWAUlTZdb0cFESpxmn6r5io1VPTmgczqH51KgQOHnkuk0XipL2LRyHqJR6W1qJ1XoRIVcsE63rRajqB3w3mq2YL4lCi8v+xFd8jU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790567884; c=relaxed/simple; bh=RCb84R1Ilbqk/brMo0ozsD4weTDX3UUsJYqs8fer/vM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mOT50B+VZsg5tiXCdlJ7R1Rjj4Ag9W0vstl5ndjFeTNRtuic0Vcw7mffkGm5yaK1g1tlG9LORaMeADIbssa7/fAT3goFyML+U6ocQ83ku3efR/MMRCxNRyrB9ierAOl58QjSUjsU+iYqxOl+YvEqTkkBSpPe4PoKubdqYB5pb/s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=CE+5RxAk; arc=none smtp.client-ip=74.125.227.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="CE+5RxAk" Received: by mail-vs2-f43.google.com with SMTP id ada2fe7eead31-790b4aeb66bso1318026137.0 for ; Sun, 27 Sep 2026 20:58:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790567882; x=1791172682; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=8PRQtLnkGcQLLad/iSnwkqrL/4wKHSNHecCDuETOGrQ=; b=CE+5RxAkoZPF2ZDyvTb4nIJQXt18JC74S5W5fHZRCroLzNEnPs11sUoEz23V/sT3Z8 SVhKP+SJOvXap51n1nPCYIk92nSJ52oJMKqJPcKWpK2GQwxguKxijjjHd6/azrnwnmkM Q2hOTulTf7+QyEUR2CGdNKcbuKfSBh6c0A+X3X/NPcY6h0zP1fWMe7h23OFZIl2gymI/ ayxf4a8x9I09g9E1PEv4xgQAVbQryQ6Rk9/r0/SlbaMcqe/D1Wrr+nfcrZrT6ih/oGMB 8dskjENNoAK3R9kQUmjMBNV9e+GBQYXGDdYuK7XUj63GnU+U0oou6DIakZPLGORJOKcR py4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790567882; x=1791172682; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=8PRQtLnkGcQLLad/iSnwkqrL/4wKHSNHecCDuETOGrQ=; b=mgeqc0GZGs6SU/Ioo43yLrE8/EqqRuyOR89L9+PaPrYSjBXLH9vKllGOLHt8jlHgMx aOyGBLIjBhmUv5T4ZjHZR/JxC2Lip9iuL529XQ24VEKhgUD3n25ShhSkt2ppx5lZmITY OvPGCIbe5BJI6K2k6ezXchjDf+z/InRH2iVnTSjGxx//Ued08n5tJNePR8PDOoxghOFm 5SJKNUfXUUZNW8aPtxRLT07TLcjzsb+aU9IySs6ADGEqWP5lJZ5hvIisgh+zksDGKQYR u5Sduop9UNkKs+XkG68bcGL2nZ/1JS5aXBkf+yQZ/pVXvnopIk1UbM3ZNAR6culMq+Br peIQ== X-Forwarded-Encrypted: i=1; AKwUvByLGSOt+AfOl/YiRooebn76xCQSJaVRDqld+ndrAh6fp2hoQyr/EKW3Muu+qxrEE6D4t9UHPhATWB7rGkE=@vger.kernel.org X-Gm-Message-State: AFq9FYJjrCsOFLbkXLxoO+EtEMInnGu1uxYqXU+0caj9HCb5wWDLaXu7 AIp3rGeVrlOgQjxeFtj5awj80lXhK7ySo5U7vOd9ao9q/TUXETADdHVH X-Gm-Gg: AYBFou0WJtz97YlDFNsirnFSp8v7dlfaoVewdn+axWuJu061HwWUFQBnmlpb/FLy2bK RhSFrLqoZhSZiStXhHVOBhBhMWcgd53tMXebI3MmzCU2aH27OwyKCFRnEzbS118OFYQ22gPjBkk z/YCNqPS7XqzrqcF5jnnk71kGFUNGS1N27jU3sK0odB1m7bwDjz3tmxNZhwpIskVc1PRVJ3EXql 9OVGFSlOoMQfyjNSYnTdGwUcud1K25VwujKBzvfZjdiexOmdmsWq5d2D5fnYXlO4gpaJkohUr5m MlTcuwEee7iQdWjcwj7w/AKeUxZVw+tVpjcq4aWMOj76xfvZfzZYRsHUyyZDrA30Y7Q600vlldx r/+t4Ue3qpFDrJ3mj0CtojwROquoR60RyDiXhnywq48TQ/HAgYIeBZt68UF9FhWX1KgWO0EltEh qM9zj540YN7ixYLG+v9wd3b8hHNntb/fpcXsTmH4+JhERr8kvt42kq9Vs3nk9f59M= X-Received: by 2002:a05:6102:358d:b0:79e:2b00:b4da with SMTP id ada2fe7eead31-7af1c692c06mr4663990137.6.1790567882180; Sun, 27 Sep 2026 20:58:02 -0700 (PDT) Received: from beelink.. ([187.13.30.172]) by smtp.gmail.com with ESMTPSA id ada2fe7eead31-7b39b15808esm8107452137.5.2026.09.27.20.57.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 27 Sep 2026 20:58:01 -0700 (PDT) From: Aldo Ariel Panzardo To: david@ixit.cz, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: horms@kernel.org, oe-linux-nfc@lists.linux.dev, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, syzbot+ci3c472c63e196fe9e@syzkaller.appspotmail.com, Aldo Ariel Panzardo , Sashiko Subject: [PATCH net v3] nfc: llcp: prevent resource leak on repeated connect after DM Date: Mon, 28 Sep 2026 00:57:49 -0300 Message-ID: <20260928035749.2305913-1-qwe.aldo@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260925184857.357926-1-qwe.aldo@gmail.com> References: <20260925184857.357926-1-qwe.aldo@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit A rejected asynchronous connect leaves a local reference, SAP allocation, service name and device reference on a closed socket. Release them before retrying connect. The device pointer alone does not prove ownership: bind() puts its temporary device reference while retaining the pointer. When device teardown closes a bound socket, the retry cleanup would put that device again. Clear the pointer when a bound or listening socket becomes closed, and after a connected socket's device reference is put. Do the same when DM closes a bound or listening socket. A DM rejected connect keeps its device reference until the retry cleanup, so retain that put there. Fixes: d646960f7986 ("NFC: Initial LLCP support") Reported-by: Sashiko Link: https://ci.syzbot.org/findings/64002827-5231-4183-bfca-0d91bded8543/syz_repro Cc: stable@vger.kernel.org Signed-off-by: Aldo Ariel Panzardo --- v3: Clear non-owning or already released device pointers on close, while preserving the device put for rejected asynchronous connects. net/nfc/llcp_core.c | 12 +++++++++++- net/nfc/llcp_sock.c | 17 +++++++++++++++++ 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c index 199543c47eef..6382aacca69a 100644 --- a/net/nfc/llcp_core.c +++ b/net/nfc/llcp_core.c @@ -95,8 +95,14 @@ nfc_llcp_socket_purge(llcp_sock); - if (sk->sk_state == LLCP_CONNECTED) + if (sk->sk_state == LLCP_CONNECTED) { nfc_put_device(llcp_sock->dev); + llcp_sock->dev = NULL; + } else if (sk->sk_state == LLCP_BOUND || + sk->sk_state == LLCP_LISTEN) { + /* bind() already dropped its temporary device reference. */ + llcp_sock->dev = NULL; + } if (sk->sk_state == LLCP_LISTEN) { struct nfc_llcp_sock *lsk, *n; @@ -1330,6 +1336,10 @@ if (connecting) nfc_llcp_sock_unlink(&local->connecting_sockets, sk); + /* Bound and listening sockets do not own a device reference. */ + if (sk->sk_state == LLCP_BOUND || sk->sk_state == LLCP_LISTEN) + llcp_sock->dev = NULL; + sk->sk_err = ENXIO; sk->sk_state = LLCP_CLOSED; sk->sk_state_change(sk); diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c index 1e5ee4bcde68..9d76c12aee01 100644 --- a/net/nfc/llcp_sock.c +++ b/net/nfc/llcp_sock.c @@ -713,6 +713,23 @@ if (sk->sk_state == LLCP_CONNECTING) { ret = -EINPROGRESS; goto error; + } + + if (sk->sk_state == LLCP_CLOSED) { + /* Release resources retained by a previous failed connection. */ + if (llcp_sock->local) { + if (llcp_sock->reserved_ssap < LLCP_SAP_MAX) + nfc_llcp_put_ssap(llcp_sock->local, llcp_sock->ssap); + nfc_llcp_local_put(llcp_sock->local); + } + if (llcp_sock->dev) + nfc_put_device(llcp_sock->dev); + kfree(llcp_sock->service_name); + llcp_sock->local = NULL; + llcp_sock->dev = NULL; + llcp_sock->service_name = NULL; + llcp_sock->service_name_len = 0; + llcp_sock->reserved_ssap = LLCP_SAP_MAX; } dev = nfc_get_device(addr->dev_idx); -- 2.43.0