linux-cve-announce - CVE-2024-56772: kunit: string-stream: Fix a UAF bug in kunit_init

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <2025010810-CVE-2024-56772-a64d@gregkh>
Date: Wed,  8 Jan 2025 18:49:10 +0100
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: CVE-2024-56772: kunit: string-stream: Fix a UAF bug in kunit_init_suite()

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

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

kunit: string-stream: Fix a UAF bug in kunit_init_suite()

In kunit_debugfs_create_suite(), if alloc_string_stream() fails in the
kunit_suite_for_each_test_case() loop, the "suite->log = stream"
has assigned before, and the error path only free the suite->log's stream
memory but not set it to NULL, so the later string_stream_clear() of
suite->log in kunit_init_suite() will cause below UAF bug.

Set stream pointer to NULL after free to fix it.

	Unable to handle kernel paging request at virtual address 006440150000030d
	Mem abort info:
	  ESR = 0x0000000096000004
	  EC = 0x25: DABT (current EL), IL = 32 bits
	  SET = 0, FnV = 0
	  EA = 0, S1PTW = 0
	  FSC = 0x04: level 0 translation fault
	Data abort info:
	  ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
	  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
	  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
	[006440150000030d] address between user and kernel address ranges
	Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
	Dumping ftrace buffer:
	   (ftrace buffer empty)
	Modules linked in: iio_test_gts industrialio_gts_helper cfg80211 rfkill ipv6 [last unloaded: iio_test_gts]
	CPU: 5 UID: 0 PID: 6253 Comm: modprobe Tainted: G    B   W        N 6.12.0-rc4+ #458
	Tainted: [B]=BAD_PAGE, [W]=WARN, [N]=TEST
	Hardware name: linux,dummy-virt (DT)
	pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
	pc : string_stream_clear+0x54/0x1ac
	lr : string_stream_clear+0x1a8/0x1ac
	sp : ffffffc080b47410
	x29: ffffffc080b47410 x28: 006440550000030d x27: ffffff80c96b5e98
	x26: ffffff80c96b5e80 x25: ffffffe461b3f6c0 x24: 0000000000000003
	x23: ffffff80c96b5e88 x22: 1ffffff019cdf4fc x21: dfffffc000000000
	x20: ffffff80ce6fa7e0 x19: 032202a80000186d x18: 0000000000001840
	x17: 0000000000000000 x16: 0000000000000000 x15: ffffffe45c355cb4
	x14: ffffffe45c35589c x13: ffffffe45c03da78 x12: ffffffb810168e75
	x11: 1ffffff810168e74 x10: ffffffb810168e74 x9 : dfffffc000000000
	x8 : 0000000000000004 x7 : 0000000000000003 x6 : 0000000000000001
	x5 : ffffffc080b473a0 x4 : 0000000000000000 x3 : 0000000000000000
	x2 : 0000000000000001 x1 : ffffffe462fbf620 x0 : dfffffc000000000
	Call trace:
	 string_stream_clear+0x54/0x1ac
	 __kunit_test_suites_init+0x108/0x1d8
	 kunit_exec_run_tests+0xb8/0x100
	 kunit_module_notify+0x400/0x55c
	 notifier_call_chain+0xfc/0x3b4
	 blocking_notifier_call_chain+0x68/0x9c
	 do_init_module+0x24c/0x5c8
	 load_module+0x4acc/0x4e90
	 init_module_from_file+0xd4/0x128
	 idempotent_init_module+0x2d4/0x57c
	 __arm64_sys_finit_module+0xac/0x100
	 invoke_syscall+0x6c/0x258
	 el0_svc_common.constprop.0+0x160/0x22c
	 do_el0_svc+0x44/0x5c
	 el0_svc+0x48/0xb8
	 el0t_64_sync_handler+0x13c/0x158
	 el0t_64_sync+0x190/0x194
	Code: f9400753 d2dff800 f2fbffe0 d343fe7c (38e06b80)
	---[ end trace 0000000000000000 ]---
	Kernel panic - not syncing: Oops: Fatal exception

The Linux kernel CVE team has assigned CVE-2024-56772 to this issue.


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

	Issue introduced in 6.7 with commit a3fdf784780ccb0008d630e8722d1389c49c7499 and fixed in 6.12.4 with commit 3213b92754b94dec6836e8b4d6ec7d224a805b61
	Issue introduced in 6.7 with commit a3fdf784780ccb0008d630e8722d1389c49c7499 and fixed in 6.13-rc1 with commit 39e21403c978862846fa68b7f6d06f9cca235194

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-2024-56772
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:
	lib/kunit/debugfs.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/3213b92754b94dec6836e8b4d6ec7d224a805b61
	https://git.kernel.org/stable/c/39e21403c978862846fa68b7f6d06f9cca235194