cve/published/2024/CVE-2024-57834.mbox

From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: <linux-cve-announce@vger.kernel.org>
Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org>
Subject: CVE-2024-57834: media: vidtv: Fix a null-ptr-deref in vidtv_mux_stop_thread

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

media: vidtv: Fix a null-ptr-deref in vidtv_mux_stop_thread

syzbot report a null-ptr-deref in vidtv_mux_stop_thread. [1]

If dvb->mux is not initialized successfully by vidtv_mux_init() in the
vidtv_start_streaming(), it will trigger null pointer dereference about mux
in vidtv_mux_stop_thread().

Adjust the timing of streaming initialization and check it before
stopping it.

[1]
KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f]
CPU: 0 UID: 0 PID: 5842 Comm: syz-executor248 Not tainted 6.13.0-rc4-syzkaller-00012-g9b2ffa6148b1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:vidtv_mux_stop_thread+0x26/0x80 drivers/media/test-drivers/vidtv/vidtv_mux.c:471
Code: 90 90 90 90 66 0f 1f 00 55 53 48 89 fb e8 82 2e c8 f9 48 8d bb 28 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 02 7e 3b 0f b6 ab 28 01 00 00 31 ff 89 ee e8
RSP: 0018:ffffc90003f2faa8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87cfb125
RDX: 0000000000000025 RSI: ffffffff87d120ce RDI: 0000000000000128
RBP: ffff888029b8d220 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: ffff888029b8d188
R13: ffffffff8f590aa0 R14: ffffc9000581c5c8 R15: ffff888029a17710
FS:  00007f7eef5156c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7eef5e635c CR3: 0000000076ca6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 vidtv_stop_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:209 [inline]
 vidtv_stop_feed+0x151/0x250 drivers/media/test-drivers/vidtv/vidtv_bridge.c:252
 dmx_section_feed_stop_filtering+0x90/0x160 drivers/media/dvb-core/dvb_demux.c:1000
 dvb_dmxdev_feed_stop.isra.0+0x1ee/0x270 drivers/media/dvb-core/dmxdev.c:486
 dvb_dmxdev_filter_stop+0x22a/0x3a0 drivers/media/dvb-core/dmxdev.c:559
 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline]
 dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246
 __fput+0x3f8/0xb60 fs/file_table.c:450
 task_work_run+0x14e/0x250 kernel/task_work.c:239
 get_signal+0x1d3/0x2610 kernel/signal.c:2790
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The Linux kernel CVE team has assigned CVE-2024-57834 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 5.10.235 with commit 52d3512f9a7a52ef92864679b1e8e8aa16202c6a
	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 5.15.179 with commit 59a707ad952eb2ea8d59457d662b6f4138f17b08
	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 6.1.129 with commit 86307e443c5844f38e1b98e2c51a4195c55576cd
	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 6.6.79 with commit 2c5601b99d79d196fe4a37159e3dfb38e778ea18
	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 6.12.16 with commit 95432a37778c9c5dd105b7b9f19e9695c9e166cf
	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 6.13.4 with commit 904a8323cc8afa7eb9ce3e67303a2b3f2f787306
	Issue introduced in 5.10 with commit f90cf6079bf67988f8b1ad1ade70fc89d0080905 and fixed in 6.14 with commit 1221989555db711578a327a9367f1be46500cb48

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-57834
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/media/test-drivers/vidtv/vidtv_bridge.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/52d3512f9a7a52ef92864679b1e8e8aa16202c6a
	https://git.kernel.org/stable/c/59a707ad952eb2ea8d59457d662b6f4138f17b08
	https://git.kernel.org/stable/c/86307e443c5844f38e1b98e2c51a4195c55576cd
	https://git.kernel.org/stable/c/2c5601b99d79d196fe4a37159e3dfb38e778ea18
	https://git.kernel.org/stable/c/95432a37778c9c5dd105b7b9f19e9695c9e166cf
	https://git.kernel.org/stable/c/904a8323cc8afa7eb9ce3e67303a2b3f2f787306
	https://git.kernel.org/stable/c/1221989555db711578a327a9367f1be46500cb48