CVE-2025-38677

Published Aug 30, 2025

Last updated a month ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid out-of-boundary access in dnode page As Jiaming Zhang reported: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x1c1/0x2a0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x17e/0x800 mm/kasan/report.c:480 kasan_report+0x147/0x180 mm/kasan/report.c:593 data_blkaddr fs/f2fs/f2fs.h:3053 [inline] f2fs_data_blkaddr fs/f2fs/f2fs.h:3058 [inline] f2fs_get_dnode_of_data+0x1a09/0x1c40 fs/f2fs/node.c:855 f2fs_reserve_block+0x53/0x310 fs/f2fs/data.c:1195 prepare_write_begin fs/f2fs/data.c:3395 [inline] f2fs_write_begin+0xf39/0x2190 fs/f2fs/data.c:3594 generic_perform_write+0x2c7/0x910 mm/filemap.c:4112 f2fs_buffered_write_iter fs/f2fs/file.c:4988 [inline] f2fs_file_write_iter+0x1ec8/0x2410 fs/f2fs/file.c:5216 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x546/0xa90 fs/read_write.c:686 ksys_write+0x149/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x3d0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The root cause is in the corrupted image, there is a dnode has the same node id w/ its inode, so during f2fs_get_dnode_of_data(), it tries to access block address in dnode at offset 934, however it parses the dnode as inode node, so that get_dnode_addr() returns 360, then it tries to access page address from 360 + 934 * 4 = 4096 w/ 4 bytes. To fix this issue, let's add sanity check for node id of all direct nodes during f2fs_get_dnode_of_data().
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel, debian_linux

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

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