CVE-2023-53108

Published May 2, 2025

Last updated a year ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: net/iucv: Fix size of interrupt data iucv_irq_data needs to be 4 bytes larger. These bytes are not used by the iucv module, but written by the z/VM hypervisor in case a CPU is deconfigured. Reported as: BUG dma-kmalloc-64 (Not tainted): kmalloc Redzone overwritten ----------------------------------------------------------------------------- 0x0000000000400564-0x0000000000400567 @offset=1380. First byte 0x80 instead of 0xcc Allocated in iucv_cpu_prepare+0x44/0xd0 age=167839 cpu=2 pid=1 __kmem_cache_alloc_node+0x166/0x450 kmalloc_node_trace+0x3a/0x70 iucv_cpu_prepare+0x44/0xd0 cpuhp_invoke_callback+0x156/0x2f0 cpuhp_issue_call+0xf0/0x298 __cpuhp_setup_state_cpuslocked+0x136/0x338 __cpuhp_setup_state+0xf4/0x288 iucv_init+0xf4/0x280 do_one_initcall+0x78/0x390 do_initcalls+0x11a/0x140 kernel_init_freeable+0x25e/0x2a0 kernel_init+0x2e/0x170 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 Freed in iucv_init+0x92/0x280 age=167839 cpu=2 pid=1 __kmem_cache_free+0x308/0x358 iucv_init+0x92/0x280 do_one_initcall+0x78/0x390 do_initcalls+0x11a/0x140 kernel_init_freeable+0x25e/0x2a0 kernel_init+0x2e/0x170 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 Slab 0x0000037200010000 objects=32 used=30 fp=0x0000000000400640 flags=0x1ffff00000010200(slab|head|node=0|zone=0| Object 0x0000000000400540 @offset=1344 fp=0x0000000000000000 Redzone 0000000000400500: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400510: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400520: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400530: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Object 0000000000400540: 00 01 00 03 00 00 00 00 00 00 00 00 00 00 00 00 ................ Object 0000000000400550: f3 86 81 f2 f4 82 f8 82 f0 f0 f0 f0 f0 f0 f0 f2 ................ Object 0000000000400560: 00 00 00 00 80 00 00 00 cc cc cc cc cc cc cc cc ................ Object 0000000000400570: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................ Redzone 0000000000400580: cc cc cc cc cc cc cc cc ........ Padding 00000000004005d4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding 00000000004005e4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding 00000000004005f4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZ CPU: 6 PID: 121030 Comm: 116-pai-crypto. Not tainted 6.3.0-20230221.rc0.git4.99b8246b2d71.300.fc37.s390x+debug #1 Hardware name: IBM 3931 A01 704 (z/VM 7.3.0) Call Trace: [<000000032aa034ec>] dump_stack_lvl+0xac/0x100 [<0000000329f5a6cc>] check_bytes_and_report+0x104/0x140 [<0000000329f5aa78>] check_object+0x370/0x3c0 [<0000000329f5ede6>] free_debug_processing+0x15e/0x348 [<0000000329f5f06a>] free_to_partial_list+0x9a/0x2f0 [<0000000329f5f4a4>] __slab_free+0x1e4/0x3a8 [<0000000329f61768>] __kmem_cache_free+0x308/0x358 [<000000032a91465c>] iucv_cpu_dead+0x6c/0x88 [<0000000329c2fc66>] cpuhp_invoke_callback+0x156/0x2f0 [<000000032aa062da>] _cpu_down.constprop.0+0x22a/0x5e0 [<0000000329c3243e>] cpu_device_down+0x4e/0x78 [<000000032a61dee0>] device_offline+0xc8/0x118 [<000000032a61e048>] online_store+0x60/0xe0 [<000000032a08b6b0>] kernfs_fop_write_iter+0x150/0x1e8 [<0000000329fab65c>] vfs_write+0x174/0x360 [<0000000329fab9fc>] ksys_write+0x74/0x100 [<000000032aa03a5a>] __do_syscall+0x1da/0x208 [<000000032aa177b2>] system_call+0x82/0xb0 INFO: lockdep is turned off. FIX dma-kmalloc-64: Restoring kmalloc Redzone 0x0000000000400564-0x0000000000400567=0xcc FIX dma-kmalloc-64: Object at 0x0000000000400540 not freed
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
NVD-CWE-noinfo

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