Description
In the Linux kernel, the following vulnerability has been resolved:

io_uring: fix use-after-free of sq->thread in __io_uring_show_fdinfo()

syzbot reports:

BUG: KASAN: slab-use-after-free in getrusage+0x1109/0x1a60
Read of size 8 at addr ffff88810de2d2c8 by task a.out/304

CPU: 0 UID: 0 PID: 304 Comm: a.out Not tainted 6.16.0-rc1 #1 PREEMPT(voluntary)
Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x53/0x70
print_report+0xd0/0x670
? __pfx__raw_spin_lock_irqsave+0x10/0x10
? getrusage+0x1109/0x1a60
kasan_report+0xce/0x100
? getrusage+0x1109/0x1a60
getrusage+0x1109/0x1a60
? __pfx_getrusage+0x10/0x10
__io_uring_show_fdinfo+0x9fe/0x1790
? ksys_read+0xf7/0x1c0
? do_syscall_64+0xa4/0x260
? vsnprintf+0x591/0x1100
? __pfx___io_uring_show_fdinfo+0x10/0x10
? __pfx_vsnprintf+0x10/0x10
? mutex_trylock+0xcf/0x130
? __pfx_mutex_trylock+0x10/0x10
? __pfx_show_fd_locks+0x10/0x10
? io_uring_show_fdinfo+0x57/0x80
io_uring_show_fdinfo+0x57/0x80
seq_show+0x38c/0x690
seq_read_iter+0x3f7/0x1180
? inode_set_ctime_current+0x160/0x4b0
seq_read+0x271/0x3e0
? __pfx_seq_read+0x10/0x10
? __pfx__raw_spin_lock+0x10/0x10
? __mark_inode_dirty+0x402/0x810
? selinux_file_permission+0x368/0x500
? file_update_time+0x10f/0x160
vfs_read+0x177/0xa40
? __pfx___handle_mm_fault+0x10/0x10
? __pfx_vfs_read+0x10/0x10
? mutex_lock+0x81/0xe0
? __pfx_mutex_lock+0x10/0x10
? fdget_pos+0x24d/0x4b0
ksys_read+0xf7/0x1c0
? __pfx_ksys_read+0x10/0x10
? do_user_addr_fault+0x43b/0x9c0
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f74170fc9
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 8
RSP: 002b:00007fffece049e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0f74170fc9
RDX: 0000000000001000 RSI: 00007fffece049f0 RDI: 0000000000000004
RBP: 00007fffece05ad0 R08: 0000000000000000 R09: 00007fffece04d90
R10: 0000000000000000 R11: 0000000000000206 R12: 00005651720a1100
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>

Allocated by task 298:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
__kasan_slab_alloc+0x6e/0x70
kmem_cache_alloc_node_noprof+0xe8/0x330
copy_process+0x376/0x5e00
create_io_thread+0xab/0xf0
io_sq_offload_create+0x9ed/0xf20
io_uring_setup+0x12b0/0x1cc0
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 22:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x37/0x50
kmem_cache_free+0xc4/0x360
rcu_core+0x5ff/0x19f0
handle_softirqs+0x18c/0x530
run_ksoftirqd+0x20/0x30
smpboot_thread_fn+0x287/0x6c0
kthread+0x30d/0x630
ret_from_fork+0xef/0x1a0
ret_from_fork_asm+0x1a/0x30

Last potentially related work creation:
kasan_save_stack+0x33/0x60
kasan_record_aux_stack+0x8c/0xa0
__call_rcu_common.constprop.0+0x68/0x940
__schedule+0xff2/0x2930
__cond_resched+0x4c/0x80
mutex_lock+0x5c/0xe0
io_uring_del_tctx_node+0xe1/0x2b0
io_uring_clean_tctx+0xb7/0x160
io_uring_cancel_generic+0x34e/0x760
do_exit+0x240/0x2350
do_group_exit+0xab/0x220
__x64_sys_exit_group+0x39/0x40
x64_sys_call+0x1243/0x1840
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88810de2cb00
which belongs to the cache task_struct of size 3712
The buggy address is located 1992 bytes inside of
freed 3712-byte region [ffff88810de2cb00, ffff88810de2d980)

which is caused by the task_struct pointed to by sq->thread being
released while it is being used in the function
__io_uring_show_fdinfo(). Holding ctx->uring_lock does not prevent ehre
relase or exit of sq->thread.

Fix this by assigning and looking up ->thread under RCU, and grabbing a
reference to the task_struct. This e
---truncated---
Published: 2025-07-03
Score: 7.8 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories
Source ID Title
EUVD EUVD EUVD-2025-19837 In the Linux kernel, the following vulnerability has been resolved: io_uring: fix use-after-free of sq->thread in __io_uring_show_fdinfo() syzbot reports: BUG: KASAN: slab-use-after-free in getrusage+0x1109/0x1a60 Read of size 8 at addr ffff88810de2d2c8 by task a.out/304 CPU: 0 UID: 0 PID: 304 Comm: a.out Not tainted 6.16.0-rc1 #1 PREEMPT(voluntary) Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xd0/0x670 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? getrusage+0x1109/0x1a60 kasan_report+0xce/0x100 ? getrusage+0x1109/0x1a60 getrusage+0x1109/0x1a60 ? __pfx_getrusage+0x10/0x10 __io_uring_show_fdinfo+0x9fe/0x1790 ? ksys_read+0xf7/0x1c0 ? do_syscall_64+0xa4/0x260 ? vsnprintf+0x591/0x1100 ? __pfx___io_uring_show_fdinfo+0x10/0x10 ? __pfx_vsnprintf+0x10/0x10 ? mutex_trylock+0xcf/0x130 ? __pfx_mutex_trylock+0x10/0x10 ? __pfx_show_fd_locks+0x10/0x10 ? io_uring_show_fdinfo+0x57/0x80 io_uring_show_fdinfo+0x57/0x80 seq_show+0x38c/0x690 seq_read_iter+0x3f7/0x1180 ? inode_set_ctime_current+0x160/0x4b0 seq_read+0x271/0x3e0 ? __pfx_seq_read+0x10/0x10 ? __pfx__raw_spin_lock+0x10/0x10 ? __mark_inode_dirty+0x402/0x810 ? selinux_file_permission+0x368/0x500 ? file_update_time+0x10f/0x160 vfs_read+0x177/0xa40 ? __pfx___handle_mm_fault+0x10/0x10 ? __pfx_vfs_read+0x10/0x10 ? mutex_lock+0x81/0xe0 ? __pfx_mutex_lock+0x10/0x10 ? fdget_pos+0x24d/0x4b0 ksys_read+0xf7/0x1c0 ? __pfx_ksys_read+0x10/0x10 ? do_user_addr_fault+0x43b/0x9c0 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0f74170fc9 Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 8 RSP: 002b:00007fffece049e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0f74170fc9 RDX: 0000000000001000 RSI: 00007fffece049f0 RDI: 0000000000000004 RBP: 00007fffece05ad0 R08: 0000000000000000 R09: 00007fffece04d90 R10: 0000000000000000 R11: 0000000000000206 R12: 00005651720a1100 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 298: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x6e/0x70 kmem_cache_alloc_node_noprof+0xe8/0x330 copy_process+0x376/0x5e00 create_io_thread+0xab/0xf0 io_sq_offload_create+0x9ed/0xf20 io_uring_setup+0x12b0/0x1cc0 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 22: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x37/0x50 kmem_cache_free+0xc4/0x360 rcu_core+0x5ff/0x19f0 handle_softirqs+0x18c/0x530 run_ksoftirqd+0x20/0x30 smpboot_thread_fn+0x287/0x6c0 kthread+0x30d/0x630 ret_from_fork+0xef/0x1a0 ret_from_fork_asm+0x1a/0x30 Last potentially related work creation: kasan_save_stack+0x33/0x60 kasan_record_aux_stack+0x8c/0xa0 __call_rcu_common.constprop.0+0x68/0x940 __schedule+0xff2/0x2930 __cond_resched+0x4c/0x80 mutex_lock+0x5c/0xe0 io_uring_del_tctx_node+0xe1/0x2b0 io_uring_clean_tctx+0xb7/0x160 io_uring_cancel_generic+0x34e/0x760 do_exit+0x240/0x2350 do_group_exit+0xab/0x220 __x64_sys_exit_group+0x39/0x40 x64_sys_call+0x1243/0x1840 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88810de2cb00 which belongs to the cache task_struct of size 3712 The buggy address is located 1992 bytes inside of freed 3712-byte region [ffff88810de2cb00, ffff88810de2d980) which is caused by the task_struct pointed to by sq->thread being released while it is being used in the function __io_uring_show_fdinfo(). Holding ctx->uring_lock does not prevent ehre relase or exit of sq->thread. Fix this by assigning and looking up ->thread under RCU, and grabbing a reference to the task_struct. This e ---truncated---
Ubuntu USN Ubuntu USN USN-7769-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7769-2 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7769-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7770-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7771-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7789-1 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7789-2 Linux kernel (Raspberry Pi) vulnerabilities
History

Thu, 20 Nov 2025 21:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}


Fri, 04 Jul 2025 00:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate


Thu, 03 Jul 2025 09:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: io_uring: fix use-after-free of sq->thread in __io_uring_show_fdinfo() syzbot reports: BUG: KASAN: slab-use-after-free in getrusage+0x1109/0x1a60 Read of size 8 at addr ffff88810de2d2c8 by task a.out/304 CPU: 0 UID: 0 PID: 304 Comm: a.out Not tainted 6.16.0-rc1 #1 PREEMPT(voluntary) Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xd0/0x670 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? getrusage+0x1109/0x1a60 kasan_report+0xce/0x100 ? getrusage+0x1109/0x1a60 getrusage+0x1109/0x1a60 ? __pfx_getrusage+0x10/0x10 __io_uring_show_fdinfo+0x9fe/0x1790 ? ksys_read+0xf7/0x1c0 ? do_syscall_64+0xa4/0x260 ? vsnprintf+0x591/0x1100 ? __pfx___io_uring_show_fdinfo+0x10/0x10 ? __pfx_vsnprintf+0x10/0x10 ? mutex_trylock+0xcf/0x130 ? __pfx_mutex_trylock+0x10/0x10 ? __pfx_show_fd_locks+0x10/0x10 ? io_uring_show_fdinfo+0x57/0x80 io_uring_show_fdinfo+0x57/0x80 seq_show+0x38c/0x690 seq_read_iter+0x3f7/0x1180 ? inode_set_ctime_current+0x160/0x4b0 seq_read+0x271/0x3e0 ? __pfx_seq_read+0x10/0x10 ? __pfx__raw_spin_lock+0x10/0x10 ? __mark_inode_dirty+0x402/0x810 ? selinux_file_permission+0x368/0x500 ? file_update_time+0x10f/0x160 vfs_read+0x177/0xa40 ? __pfx___handle_mm_fault+0x10/0x10 ? __pfx_vfs_read+0x10/0x10 ? mutex_lock+0x81/0xe0 ? __pfx_mutex_lock+0x10/0x10 ? fdget_pos+0x24d/0x4b0 ksys_read+0xf7/0x1c0 ? __pfx_ksys_read+0x10/0x10 ? do_user_addr_fault+0x43b/0x9c0 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0f74170fc9 Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 8 RSP: 002b:00007fffece049e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0f74170fc9 RDX: 0000000000001000 RSI: 00007fffece049f0 RDI: 0000000000000004 RBP: 00007fffece05ad0 R08: 0000000000000000 R09: 00007fffece04d90 R10: 0000000000000000 R11: 0000000000000206 R12: 00005651720a1100 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 298: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x6e/0x70 kmem_cache_alloc_node_noprof+0xe8/0x330 copy_process+0x376/0x5e00 create_io_thread+0xab/0xf0 io_sq_offload_create+0x9ed/0xf20 io_uring_setup+0x12b0/0x1cc0 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 22: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x37/0x50 kmem_cache_free+0xc4/0x360 rcu_core+0x5ff/0x19f0 handle_softirqs+0x18c/0x530 run_ksoftirqd+0x20/0x30 smpboot_thread_fn+0x287/0x6c0 kthread+0x30d/0x630 ret_from_fork+0xef/0x1a0 ret_from_fork_asm+0x1a/0x30 Last potentially related work creation: kasan_save_stack+0x33/0x60 kasan_record_aux_stack+0x8c/0xa0 __call_rcu_common.constprop.0+0x68/0x940 __schedule+0xff2/0x2930 __cond_resched+0x4c/0x80 mutex_lock+0x5c/0xe0 io_uring_del_tctx_node+0xe1/0x2b0 io_uring_clean_tctx+0xb7/0x160 io_uring_cancel_generic+0x34e/0x760 do_exit+0x240/0x2350 do_group_exit+0xab/0x220 __x64_sys_exit_group+0x39/0x40 x64_sys_call+0x1243/0x1840 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88810de2cb00 which belongs to the cache task_struct of size 3712 The buggy address is located 1992 bytes inside of freed 3712-byte region [ffff88810de2cb00, ffff88810de2d980) which is caused by the task_struct pointed to by sq->thread being released while it is being used in the function __io_uring_show_fdinfo(). Holding ctx->uring_lock does not prevent ehre relase or exit of sq->thread. Fix this by assigning and looking up ->thread under RCU, and grabbing a reference to the task_struct. This e ---truncated---
Title io_uring: fix use-after-free of sq->thread in __io_uring_show_fdinfo()
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-05-11T21:21:22.621Z

Reserved: 2025-04-16T04:51:23.985Z

Link: CVE-2025-38106

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-07-03T09:15:24.123

Modified: 2025-11-20T21:36:43.990

Link: CVE-2025-38106

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-07-03T00:00:00Z

Links: CVE-2025-38106 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-13T21:48:04Z

Weaknesses