CVE-2022-49395

Published Feb 26, 2025

Last updated 8 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: um: Fix out-of-bounds read in LDT setup syscall_stub_data() expects the data_count parameter to be the number of longs, not bytes. ================================================================== BUG: KASAN: stack-out-of-bounds in syscall_stub_data+0x70/0xe0 Read of size 128 at addr 000000006411f6f0 by task swapper/1 CPU: 0 PID: 1 Comm: swapper Not tainted 5.18.0+ #18 Call Trace: show_stack.cold+0x166/0x2a7 __dump_stack+0x3a/0x43 dump_stack_lvl+0x1f/0x27 print_report.cold+0xdb/0xf81 kasan_report+0x119/0x1f0 kasan_check_range+0x3a3/0x440 memcpy+0x52/0x140 syscall_stub_data+0x70/0xe0 write_ldt_entry+0xac/0x190 init_new_ldt+0x515/0x960 init_new_context+0x2c4/0x4d0 mm_init.constprop.0+0x5ed/0x760 mm_alloc+0x118/0x170 0x60033f48 do_one_initcall+0x1d7/0x860 0x60003e7b kernel_init+0x6e/0x3d4 new_thread_handler+0x1e7/0x2c0 The buggy address belongs to stack of task swapper/1 and is located at offset 64 in frame: init_new_ldt+0x0/0x960 This frame has 2 objects: [32, 40) 'addr' [64, 80) 'desc' ==================================================================
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.1
Impact score
5.2
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-125
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-125

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