CVE-2023-53265

Published Sep 16, 2025

Last updated 9 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ubi: ensure that VID header offset + VID header size <= alloc, size Ensure that the VID header offset + VID header size does not exceed the allocated area to avoid slab OOB. BUG: KASAN: slab-out-of-bounds in crc32_body lib/crc32.c:111 [inline] BUG: KASAN: slab-out-of-bounds in crc32_le_generic lib/crc32.c:179 [inline] BUG: KASAN: slab-out-of-bounds in crc32_le_base+0x58c/0x626 lib/crc32.c:197 Read of size 4 at addr ffff88802bb36f00 by task syz-executor136/1555 CPU: 2 PID: 1555 Comm: syz-executor136 Tainted: G W 6.0.0-1868 #1 Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7860+a7792d29 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x85/0xad lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold.13+0xb6/0x6bb mm/kasan/report.c:433 kasan_report+0xa7/0x11b mm/kasan/report.c:495 crc32_body lib/crc32.c:111 [inline] crc32_le_generic lib/crc32.c:179 [inline] crc32_le_base+0x58c/0x626 lib/crc32.c:197 ubi_io_write_vid_hdr+0x1b7/0x472 drivers/mtd/ubi/io.c:1067 create_vtbl+0x4d5/0x9c4 drivers/mtd/ubi/vtbl.c:317 create_empty_lvol drivers/mtd/ubi/vtbl.c:500 [inline] ubi_read_volume_table+0x67b/0x288a drivers/mtd/ubi/vtbl.c:812 ubi_attach+0xf34/0x1603 drivers/mtd/ubi/attach.c:1601 ubi_attach_mtd_dev+0x6f3/0x185e drivers/mtd/ubi/build.c:965 ctrl_cdev_ioctl+0x2db/0x347 drivers/mtd/ubi/cdev.c:1043 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x213 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3e/0x86 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0x0 RIP: 0033:0x7f96d5cf753d Code: RSP: 002b:00007fffd72206f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f96d5cf753d RDX: 0000000020000080 RSI: 0000000040186f40 RDI: 0000000000000003 RBP: 0000000000400cd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400be0 R13: 00007fffd72207e0 R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 1555: kasan_save_stack+0x20/0x3d mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc mm/kasan/common.c:516 [inline] __kasan_kmalloc+0x88/0xa3 mm/kasan/common.c:525 kasan_kmalloc include/linux/kasan.h:234 [inline] __kmalloc+0x138/0x257 mm/slub.c:4429 kmalloc include/linux/slab.h:605 [inline] ubi_alloc_vid_buf drivers/mtd/ubi/ubi.h:1093 [inline] create_vtbl+0xcc/0x9c4 drivers/mtd/ubi/vtbl.c:295 create_empty_lvol drivers/mtd/ubi/vtbl.c:500 [inline] ubi_read_volume_table+0x67b/0x288a drivers/mtd/ubi/vtbl.c:812 ubi_attach+0xf34/0x1603 drivers/mtd/ubi/attach.c:1601 ubi_attach_mtd_dev+0x6f3/0x185e drivers/mtd/ubi/build.c:965 ctrl_cdev_ioctl+0x2db/0x347 drivers/mtd/ubi/cdev.c:1043 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x213 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3e/0x86 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0x0 The buggy address belongs to the object at ffff88802bb36e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 0 bytes to the right of 256-byte region [ffff88802bb36e00, ffff88802bb36f00) The buggy address belongs to the physical page: page:00000000ea4d1263 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bb36 head:00000000ea4d1263 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0010200 ffffea000066c300 dead000000000003 ffff888100042b40 raw: 0000000000000000 00000000001 ---truncated---
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: cgroup: Avoid iteration of dying tasks with zero refcount The commit 260fbcb92bbea ("cgroup: Move dying_tasks cleanup from cgroup_task_release() to cgroup_task_free()") extended the lifetime of tasks on the dying_tasks list. The iterators have provision to go through dying_tasks because of dying threadgroup leaders or explicit CSS_TASK_ITER_WITH_DEAD, however, it was expected that such tasks can obtain a new reference (that is possible before cgroup_task_release()/put_task_struct_rcu_user()). The tasks after cgroup_task_release() and before cgroup_task_free() are subject to race when they may or may not have ->usage count > 0. The race window is between css_task_iter_next() invocations when css_set_lock is released and we may arrive at a new ->task_pos. The iterator should not attempt to resurrect tasks whose ->usage count dropped to zero. (When that happens, __put_task_struct_rcu_cb() is already imminent and the returned task_struct would could be used after free.) As for the fix, we cannot simply check the signal->live count of a task on the dying list because that won't distinguish regular zombies waiting to be reaped from RCU remnant tasks that are going to be free'd. Therefore add an extra check to rule out ->usage==0 tasks from any iteration. The repeat: loop in css_task_iter_advance() doesn't consider ->usage count, so add a new loop to css_task_iter_next() to skip de-used tasks on the dying_list. Rough illustration of the possible race R (reader of cgroup.procs) T (thread) L (group leader) --------------------------------- -------------------------------- -------------------------------- L exits, signal->live > 0 cgroup_task_dead(L) css_set_skip_task_iters() // skips only cset->tasks list_add_tail(&L->cg_list, &cset->dying_tasks) css_task_iter_next() take css_set_lock css_task_iter_advance() leader && signal->live != 0 => it->task_pos = &L->cg_list release css_set_lock T exits --signal->live == 0 cgroup_task_dead(T) // css_set_lock release_task(T) cgroup_task_release(T) release_task(L) // zap_leader cgroup_task_release(L) put_task_struct_rcu_user(L) ...RCU... put_task_struct(L) L->usage = 0 /* L still on dying_tasks */ ...RCU... __put_task_struct(L) css_task_iter_next() // another iteration take css_set_lock it->task_pos = &L->cg_list get_task_struct(L) => addition on 0 drop css_set_lock cgroup_task_free(L) css_set_skip_task_iters() // dying skip comes too late free_task(L) cgroup_procs_show() task_pid_vnr(L)•CVE-2026-98163