CVE-2025-38558

Published Aug 19, 2025

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: Initialize frame-based format color matching descriptor Fix NULL pointer crash in uvcg_framebased_make due to uninitialized color matching descriptor for frame-based format which was added in commit f5e7bdd34aca ("usb: gadget: uvc: Allow creating new color matching descriptors") that added handling for uncompressed and mjpeg format. Crash is seen when userspace configuration (via configfs) does not explicitly define the color matching descriptor. If color_matching is not found, config_group_find_item() returns NULL. The code then jumps to out_put_cm, where it calls config_item_put(color_matching);. If color_matching is NULL, this will dereference a null pointer, leading to a crash. [ 2.746440] Unable to handle kernel NULL pointer dereference at virtual address 000000000000008c [ 2.756273] Mem abort info: [ 2.760080] ESR = 0x0000000096000005 [ 2.764872] EC = 0x25: DABT (current EL), IL = 32 bits [ 2.771068] SET = 0, FnV = 0 [ 2.771069] EA = 0, S1PTW = 0 [ 2.771070] FSC = 0x05: level 1 translation fault [ 2.771071] Data abort info: [ 2.771072] ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 [ 2.771073] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 2.771074] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 2.771075] user pgtable: 4k pages, 39-bit VAs, pgdp=00000000a3e59000 [ 2.771077] [000000000000008c] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000 [ 2.771081] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP [ 2.771084] Dumping ftrace buffer: [ 2.771085] (ftrace buffer empty) [ 2.771138] CPU: 7 PID: 486 Comm: ln Tainted: G W E 6.6.58-android15 [ 2.771139] Hardware name: Qualcomm Technologies, Inc. SunP QRD HDK (DT) [ 2.771140] pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 2.771141] pc : __uvcg_fill_strm+0x198/0x2cc [ 2.771145] lr : __uvcg_iter_strm_cls+0xc8/0x17c [ 2.771146] sp : ffffffc08140bbb0 [ 2.771146] x29: ffffffc08140bbb0 x28: ffffff803bc81380 x27: ffffff8023bbd250 [ 2.771147] x26: ffffff8023bbd250 x25: ffffff803c361348 x24: ffffff803d8e6768 [ 2.771148] x23: 0000000000000004 x22: 0000000000000003 x21: ffffffc08140bc48 [ 2.771149] x20: 0000000000000000 x19: ffffffc08140bc48 x18: ffffffe9f8cf4a00 [ 2.771150] x17: 000000001bf64ec3 x16: 000000001bf64ec3 x15: ffffff8023bbd250 [ 2.771151] x14: 000000000000000f x13: 004c4b40000f4240 x12: 000a2c2a00051615 [ 2.771152] x11: 000000000000004f x10: ffffffe9f76b40ec x9 : ffffffe9f7e389d0 [ 2.771153] x8 : ffffff803d0d31ce x7 : 000f4240000a2c2a x6 : 0005161500028b0a [ 2.771154] x5 : ffffff803d0d31ce x4 : 0000000000000003 x3 : 0000000000000000 [ 2.771155] x2 : ffffffc08140bc50 x1 : ffffffc08140bc48 x0 : 0000000000000000 [ 2.771156] Call trace: [ 2.771157] __uvcg_fill_strm+0x198/0x2cc [ 2.771157] __uvcg_iter_strm_cls+0xc8/0x17c [ 2.771158] uvcg_streaming_class_allow_link+0x240/0x290 [ 2.771159] configfs_symlink+0x1f8/0x630 [ 2.771161] vfs_symlink+0x114/0x1a0 [ 2.771163] do_symlinkat+0x94/0x28c [ 2.771164] __arm64_sys_symlinkat+0x54/0x70 [ 2.771164] invoke_syscall+0x58/0x114 [ 2.771166] el0_svc_common+0x80/0xe0 [ 2.771168] do_el0_svc+0x1c/0x28 [ 2.771169] el0_svc+0x3c/0x70 [ 2.771172] el0t_64_sync_handler+0x68/0xbc [ 2.771173] el0t_64_sync+0x1a8/0x1ac Initialize color matching descriptor for frame-based format to prevent NULL pointer crash by mirroring the handling done for uncompressed and mjpeg formats.
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