CVE-2025-37738

Published May 1, 2025

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ext4: ignore xattrs past end Once inside 'ext4_xattr_inode_dec_ref_all' we should ignore xattrs entries past the 'end' entry. This fixes the following KASAN reported issue: ================================================================== BUG: KASAN: slab-use-after-free in ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 Read of size 4 at addr ffff888012c120c4 by task repro/2065 CPU: 1 UID: 0 PID: 2065 Comm: repro Not tainted 6.13.0-rc2+ #11 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x1fd/0x300 ? tcp_gro_dev_warn+0x260/0x260 ? _printk+0xc0/0x100 ? read_lock_is_recursive+0x10/0x10 ? irq_work_queue+0x72/0xf0 ? __virt_addr_valid+0x17b/0x4b0 print_address_description+0x78/0x390 print_report+0x107/0x1f0 ? __virt_addr_valid+0x17b/0x4b0 ? __virt_addr_valid+0x3ff/0x4b0 ? __phys_addr+0xb5/0x160 ? ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 kasan_report+0xcc/0x100 ? ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 ext4_xattr_inode_dec_ref_all+0xb8c/0xe90 ? ext4_xattr_delete_inode+0xd30/0xd30 ? __ext4_journal_ensure_credits+0x5f0/0x5f0 ? __ext4_journal_ensure_credits+0x2b/0x5f0 ? inode_update_timestamps+0x410/0x410 ext4_xattr_delete_inode+0xb64/0xd30 ? ext4_truncate+0xb70/0xdc0 ? ext4_expand_extra_isize_ea+0x1d20/0x1d20 ? __ext4_mark_inode_dirty+0x670/0x670 ? ext4_journal_check_start+0x16f/0x240 ? ext4_inode_is_fast_symlink+0x2f2/0x3a0 ext4_evict_inode+0xc8c/0xff0 ? ext4_inode_is_fast_symlink+0x3a0/0x3a0 ? do_raw_spin_unlock+0x53/0x8a0 ? ext4_inode_is_fast_symlink+0x3a0/0x3a0 evict+0x4ac/0x950 ? proc_nr_inodes+0x310/0x310 ? trace_ext4_drop_inode+0xa2/0x220 ? _raw_spin_unlock+0x1a/0x30 ? iput+0x4cb/0x7e0 do_unlinkat+0x495/0x7c0 ? try_break_deleg+0x120/0x120 ? 0xffffffff81000000 ? __check_object_size+0x15a/0x210 ? strncpy_from_user+0x13e/0x250 ? getname_flags+0x1dc/0x530 __x64_sys_unlinkat+0xc8/0xf0 do_syscall_64+0x65/0x110 entry_SYSCALL_64_after_hwframe+0x67/0x6f RIP: 0033:0x434ffd Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 8 RSP: 002b:00007ffc50fa7b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 00007ffc50fa7e18 RCX: 0000000000434ffd RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000005 RBP: 00007ffc50fa7be0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc50fa7e08 R14: 00000000004bbf30 R15: 0000000000000001 </TASK> The buggy address belongs to the object at ffff888012c12000 which belongs to the cache filp of size 360 The buggy address is located 196 bytes inside of freed 360-byte region [ffff888012c12000, ffff888012c12168) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12c12 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x40(head|node=0|zone=0) page_type: f5(slab) raw: 0000000000000040 ffff888000ad7640 ffffea0000497a00 dead000000000004 raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 0000000000000040 ffff888000ad7640 ffffea0000497a00 dead000000000004 head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000 head: 0000000000000001 ffffea00004b0481 ffffffffffffffff 0000000000000000 head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888012c11f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888012c12000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888012c12080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888012c12100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff888012c12180: fc fc fc fc fc fc fc fc fc ---truncated---
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel, debian_linux

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-416

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