CVE-2024-46793

Published Sep 18, 2024

Last updated 2 years ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ASoC: Intel: Boards: Fix NULL pointer deref in BYT/CHT boards harder Since commit 13f58267cda3 ("ASoC: soc.h: don't create dummy Component via COMP_DUMMY()") dummy codecs declared like this: SND_SOC_DAILINK_DEF(dummy, DAILINK_COMP_ARRAY(COMP_DUMMY())); expand to: static struct snd_soc_dai_link_component dummy[] = { }; Which means that dummy is a zero sized array and thus dais[i].codecs should not be dereferenced *at all* since it points to the address of the next variable stored in the data section as the "dummy" variable has an address but no size, so even dereferencing dais[0] is already an out of bounds array reference. Which means that the if (dais[i].codecs->name) check added in commit 7d99a70b6595 ("ASoC: Intel: Boards: Fix NULL pointer deref in BYT/CHT boards") relies on that the part of the next variable which the name member maps to just happens to be NULL. Which apparently so far it usually is, except when it isn't and then it results in crashes like this one: [ 28.795659] BUG: unable to handle page fault for address: 0000000000030011 ... [ 28.795780] Call Trace: [ 28.795787] <TASK> ... [ 28.795862] ? strcmp+0x18/0x40 [ 28.795872] 0xffffffffc150c605 [ 28.795887] platform_probe+0x40/0xa0 ... [ 28.795979] ? __pfx_init_module+0x10/0x10 [snd_soc_sst_bytcr_wm5102] Really fix things this time around by checking dais.num_codecs != 0.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-476

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: coresight: tmc-etr: Fix race condition between sysfs and perf mode When trying to run perf and sysfs mode simultaneously, the WARN_ON() in tmc_etr_enable_hw() is triggered sometimes: WARNING: CPU: 42 PID: 3911571 at drivers/hwtracing/coresight/coresight-tmc-etr.c:1060 tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] [..snip..] Call trace: tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] (P) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] (L) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] coresight_enable_path+0x1c8/0x218 [coresight] coresight_enable_sysfs+0xa4/0x228 [coresight] enable_source_store+0x58/0xa8 [coresight] dev_attr_store+0x20/0x40 sysfs_kf_write+0x4c/0x68 kernfs_fop_write_iter+0x120/0x1b8 vfs_write+0x2c8/0x388 ksys_write+0x74/0x108 __arm64_sys_write+0x24/0x38 el0_svc_common.constprop.0+0x64/0x148 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x130 el0t_64_sync_handler+0xc8/0xd0 el0t_64_sync+0x1ac/0x1b0 ---[ end trace 0000000000000000 ]--- Since the enablement of sysfs mode is separeted into two critical regions, one for sysfs buffer allocation and another for hardware enablement, it's possible to race with the perf mode. Fix this by double check whether the perf mode's been used before enabling the hardware in sysfs mode. mode: [sysfs mode] [perf mode] tmc_etr_get_sysfs_buffer() spin_lock(&drvdata->spinlock) [sysfs buffer allocation] spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() drvdata->etr_buf = etr_perf->etr_buf spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() WARN_ON(drvdata->etr_buf) // WARN sicne etr_buf initialized at the perf side spin_unlock(&drvdata->spinlock) With this fix, we retain the check for CS_MODE_PERF in get_etr_sysfs_buf. This ensures we verify whether the perf mode's already running before we actually allocate the buffer. Then we can save the time of allocating/freeing the sysfs buffer if race with the perf mode.CVE-2026-46272