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 8B04317592; Tue, 30 Apr 2024 11:27:22 +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=1714476442; cv=none; b=e0tNyeglg6jcZz6AXQo1QXeppNknDtfadFnXLrxwywvqZK/IcDaehFLVvlaKd+6m1dwoxGb0JMe+0q5tbIE//Lx15c39zZQ45RLhaTHT96hAh/kA47Ff1iNrZBcX4GsUgO59h2Wn3E440jttao/tLfYM4c9tW/FsNAsNpJEl/7o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714476442; c=relaxed/simple; bh=iEEIfj/U5hYqidZh5uFCop7GLy23uzXFpOYTFaZP6rs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=krjWmca8P5UEESmtrqb870EZGZI8W8fWA9Wa75J3KHnO8vcMuXNDZNLrFhkoA3QBrWcInlWNj2tdyGixfGVBYJXWFv1/B114pPFsYvYEe3PpS13HyLl0UBeazLqM8wOlmjWTHqNVhUX3CxJT4R5WkrcQa0JnGnlAUuHSLNJZ0bs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0aviCfnL; 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="0aviCfnL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF26FC2BBFC; Tue, 30 Apr 2024 11:27:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1714476442; bh=iEEIfj/U5hYqidZh5uFCop7GLy23uzXFpOYTFaZP6rs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0aviCfnLQRSc7aXhBKqH/GqTf0xs2fA/LqXWP4ckajwdqDpUj6NSk/D/vyZ3YUcaR VdTq0AfMg+vojZviSkkNjoLWOmUFW9Fzt8NnkTPrLLa/P+DpQY5U6n8y31s8QZV5Nd 9k31gFSWcv3Pxvid+rFw6uFTcgy/kCVtergmbN3k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Duoming Zhou , Paolo Abeni , Sasha Levin Subject: [PATCH 6.1 033/110] ax25: Fix netdev refcount issue Date: Tue, 30 Apr 2024 12:40:02 +0200 Message-ID: <20240430103048.546745310@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240430103047.561802595@linuxfoundation.org> References: <20240430103047.561802595@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Duoming Zhou [ Upstream commit 467324bcfe1a31ec65d0cf4aa59421d6b7a7d52b ] The dev_tracker is added to ax25_cb in ax25_bind(). When the ax25 device is detaching, the dev_tracker of ax25_cb should be deallocated in ax25_kill_by_device() instead of the dev_tracker of ax25_dev. The log reported by ref_tracker is shown below: [ 80.884935] ref_tracker: reference already released. [ 80.885150] ref_tracker: allocated in: [ 80.885349] ax25_dev_device_up+0x105/0x540 [ 80.885730] ax25_device_event+0xa4/0x420 [ 80.885730] notifier_call_chain+0xc9/0x1e0 [ 80.885730] __dev_notify_flags+0x138/0x280 [ 80.885730] dev_change_flags+0xd7/0x180 [ 80.885730] dev_ifsioc+0x6a9/0xa30 [ 80.885730] dev_ioctl+0x4d8/0xd90 [ 80.885730] sock_do_ioctl+0x1c2/0x2d0 [ 80.885730] sock_ioctl+0x38b/0x4f0 [ 80.885730] __se_sys_ioctl+0xad/0xf0 [ 80.885730] do_syscall_64+0xc4/0x1b0 [ 80.885730] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 80.885730] ref_tracker: freed in: [ 80.885730] ax25_device_event+0x272/0x420 [ 80.885730] notifier_call_chain+0xc9/0x1e0 [ 80.885730] dev_close_many+0x272/0x370 [ 80.885730] unregister_netdevice_many_notify+0x3b5/0x1180 [ 80.885730] unregister_netdev+0xcf/0x120 [ 80.885730] sixpack_close+0x11f/0x1b0 [ 80.885730] tty_ldisc_kill+0xcb/0x190 [ 80.885730] tty_ldisc_hangup+0x338/0x3d0 [ 80.885730] __tty_hangup+0x504/0x740 [ 80.885730] tty_release+0x46e/0xd80 [ 80.885730] __fput+0x37f/0x770 [ 80.885730] __x64_sys_close+0x7b/0xb0 [ 80.885730] do_syscall_64+0xc4/0x1b0 [ 80.885730] entry_SYSCALL_64_after_hwframe+0x67/0x6f [ 80.893739] ------------[ cut here ]------------ [ 80.894030] WARNING: CPU: 2 PID: 140 at lib/ref_tracker.c:255 ref_tracker_free+0x47b/0x6b0 [ 80.894297] Modules linked in: [ 80.894929] CPU: 2 PID: 140 Comm: ax25_conn_rel_6 Not tainted 6.9.0-rc4-g8cd26fd90c1a #11 [ 80.895190] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qem4 [ 80.895514] RIP: 0010:ref_tracker_free+0x47b/0x6b0 [ 80.895808] Code: 83 c5 18 4c 89 eb 48 c1 eb 03 8a 04 13 84 c0 0f 85 df 01 00 00 41 83 7d 00 00 75 4b 4c 89 ff 9 [ 80.896171] RSP: 0018:ffff888009edf8c0 EFLAGS: 00000286 [ 80.896339] RAX: 1ffff1100141ac00 RBX: 1ffff1100149463b RCX: dffffc0000000000 [ 80.896502] RDX: 0000000000000001 RSI: 0000000000000246 RDI: ffff88800a0d6518 [ 80.896925] RBP: ffff888009edf9b0 R08: ffff88806d3288d3 R09: 1ffff1100da6511a [ 80.897212] R10: dffffc0000000000 R11: ffffed100da6511b R12: ffff88800a4a31d4 [ 80.897859] R13: ffff88800a4a31d8 R14: dffffc0000000000 R15: ffff88800a0d6518 [ 80.898279] FS: 00007fd88b7fe700(0000) GS:ffff88806d300000(0000) knlGS:0000000000000000 [ 80.899436] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 80.900181] CR2: 00007fd88c001d48 CR3: 000000000993e000 CR4: 00000000000006f0 ... [ 80.935774] ref_tracker: sp%d@000000000bb9df3d has 1/1 users at [ 80.935774] ax25_bind+0x424/0x4e0 [ 80.935774] __sys_bind+0x1d9/0x270 [ 80.935774] __x64_sys_bind+0x75/0x80 [ 80.935774] do_syscall_64+0xc4/0x1b0 [ 80.935774] entry_SYSCALL_64_after_hwframe+0x67/0x6f Change ax25_dev->dev_tracker to the dev_tracker of ax25_cb in order to mitigate the bug. Fixes: feef318c855a ("ax25: fix UAF bugs of net_device caused by rebinding operation") Signed-off-by: Duoming Zhou Link: https://lore.kernel.org/r/20240419020456.29826-1-duoming@zju.edu.cn Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/ax25/af_ax25.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 6b4c25a923774..0bffac238b615 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -103,7 +103,7 @@ static void ax25_kill_by_device(struct net_device *dev) s->ax25_dev = NULL; if (sk->sk_socket) { netdev_put(ax25_dev->dev, - &ax25_dev->dev_tracker); + &s->dev_tracker); ax25_dev_put(ax25_dev); } ax25_cb_del(s); -- 2.43.0