[moderation] [fs?] KASAN: slab-use-after-free Read in clone_mnt
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syzbot
Jan 19, 2026, 2:39:30 AM (yesterday) Jan 19
to syzkaller-upst...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: 9b7977f9e39b Add linux-next specific files for 20260115
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11555052580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9c0b39f55c418575
dashboard link: https://syzkaller.appspot.com/bug?extid=b88d8faf100c16b5a67f
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/32edced7b806/disk-9b7977f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dec5450e284a/vmlinux-9b7977f9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/65783c99fb65/bzImage-9b7977f9.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b88d8f...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x4e/0x130 lib/list_debug.c:29
Read of size 8 at addr ffff8880747f4440 by task syz.5.9489/1211
CPU: 0 UID: 0 PID: 1211 Comm: syz.5.9489 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
__list_add_valid_or_report+0x4e/0x130 lib/list_debug.c:29
__list_add_valid include/linux/list.h:96 [inline]
__list_add include/linux/list.h:158 [inline]
list_add include/linux/list.h:177 [inline]
clone_mnt+0x447/0x9a0 fs/namespace.c:1286
copy_tree+0xde/0x930 fs/namespace.c:2170
copy_mnt_ns+0x11f/0x7c0 fs/namespace.c:4249
create_new_namespaces+0xcf/0x6a0 kernel/nsproxy.c:98
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3168
__do_sys_unshare kernel/fork.c:3239 [inline]
__se_sys_unshare kernel/fork.c:3237 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3237
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9df0f8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9def1f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f9df11e5fa0 RCX: 00007f9df0f8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002a060600
RBP: 00007f9df1013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9df11e6038 R14: 00007f9df11e5fa0 R15: 00007ffcc574ada8
</TASK>
Allocated by task 30875:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:5187 [inline]
slab_alloc_node mm/slub.c:5500 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5507
alloc_vfsmnt+0x23/0x420 fs/namespace.c:298
clone_mnt+0x4b/0x9a0 fs/namespace.c:1257
open_new_namespace fs/namespace.c:3110 [inline]
vfs_open_tree+0x4e8/0xf50 fs/namespace.c:3220
__do_sys_open_tree fs/namespace.c:3230 [inline]
__se_sys_open_tree fs/namespace.c:3228 [inline]
__x64_sys_open_tree+0x96/0x110 fs/namespace.c:3228
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 0:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2768 [inline]
slab_free mm/slub.c:6911 [inline]
kmem_cache_free+0x195/0x630 mm/slub.c:7022
rcu_do_batch kernel/rcu/tree.c:2617 [inline]
rcu_core+0x7bd/0x1060 kernel/rcu/tree.c:2869
handle_softirqs+0x22b/0x7c0 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x60/0x150 kernel/softirq.c:727
irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
Last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
__call_rcu_common kernel/rcu/tree.c:3131 [inline]
call_rcu+0xee/0x890 kernel/rcu/tree.c:3251
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Second to last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
task_work_add+0xb1/0x440 kernel/task_work.c:70
mntput_no_expire_slowpath+0x710/0xbe0 fs/namespace.c:1390
open_new_namespace fs/namespace.c:3175 [inline]
vfs_open_tree+0xd76/0xf50 fs/namespace.c:3220
__do_sys_open_tree fs/namespace.c:3230 [inline]
__se_sys_open_tree fs/namespace.c:3228 [inline]
__x64_sys_open_tree+0x96/0x110 fs/namespace.c:3228
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880747f4380
which belongs to the cache mnt_cache of size 352
The buggy address is located 192 bytes inside of
freed 352-byte region [ffff8880747f4380, ffff8880747f44e0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880747f4700 pfn:0x747f4
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880603d6f01
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801c2c1c80 ffffea0000e92100 dead000000000004
raw: ffff8880747f4700 0000000880120006 00000000f5000000 ffff8880603d6f01
head: 00fff00000000040 ffff88801c2c1c80 ffffea0000e92100 dead000000000004
head: ffff8880747f4700 0000000880120006 00000000f5000000 ffff8880603d6f01
head: 00fff00000000001 ffffea0001d1fd01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5822, tgid 5822 (syz-executor), ts 86866752041, free_ts 31783688525
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x23d/0x2a0 mm/page_alloc.c:1887
prep_new_page mm/page_alloc.c:1895 [inline]
get_page_from_freelist+0x23a5/0x2440 mm/page_alloc.c:3948
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5236
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
alloc_slab_page mm/slub.c:3303 [inline]
allocate_slab+0x87/0x670 mm/slub.c:3478
new_slab mm/slub.c:3536 [inline]
___slab_alloc+0xdb6/0x17b0 mm/slub.c:4890
__slab_alloc+0x65/0x100 mm/slub.c:5013
__slab_alloc_node mm/slub.c:5089 [inline]
slab_alloc_node mm/slub.c:5488 [inline]
kmem_cache_alloc_noprof+0x40f/0x710 mm/slub.c:5507
alloc_vfsmnt+0x23/0x420 fs/namespace.c:298
clone_mnt+0x4b/0x9a0 fs/namespace.c:1257
copy_tree+0x3d4/0x930 fs/namespace.c:2205
copy_mnt_ns+0x11f/0x7c0 fs/namespace.c:4249
create_new_namespaces+0xcf/0x6a0 kernel/nsproxy.c:98
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3168
__do_sys_unshare kernel/fork.c:3239 [inline]
__se_sys_unshare kernel/fork.c:3237 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3237
page last free pid 1 tgid 1 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1436 [inline]
__free_frozen_pages+0xb99/0xd10 mm/page_alloc.c:2976
__free_pages mm/page_alloc.c:5355 [inline]
free_contig_range+0x1bd/0x490 mm/page_alloc.c:7283
destroy_args+0x69/0x660 mm/debug_vm_pgtable.c:983
debug_vm_pgtable+0x38f/0x3a0 mm/debug_vm_pgtable.c:1372
do_one_initcall+0x1f1/0x800 init/main.c:1382
do_initcall_level+0x104/0x190 init/main.c:1444
do_initcalls+0x59/0xa0 init/main.c:1460
kernel_init_freeable+0x2a7/0x3e0 init/main.c:1692
kernel_init+0x1d/0x1d0 init/main.c:1582
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffff8880747f4300: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880747f4380: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880747f4400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880747f4480: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff8880747f4500: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
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(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup
syzbot found the following issue on:
HEAD commit: 9b7977f9e39b Add linux-next specific files for 20260115
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11555052580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9c0b39f55c418575
dashboard link: https://syzkaller.appspot.com/bug?extid=b88d8faf100c16b5a67f
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
CC: [bra...@kernel.org ja...@suse.cz linux-...@vger.kernel.org linux-...@vger.kernel.org vi...@zeniv.linux.org.uk]
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/32edced7b806/disk-9b7977f9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dec5450e284a/vmlinux-9b7977f9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/65783c99fb65/bzImage-9b7977f9.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b88d8f...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x4e/0x130 lib/list_debug.c:29
Read of size 8 at addr ffff8880747f4440 by task syz.5.9489/1211
CPU: 0 UID: 0 PID: 1211 Comm: syz.5.9489 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
__list_add_valid_or_report+0x4e/0x130 lib/list_debug.c:29
__list_add_valid include/linux/list.h:96 [inline]
__list_add include/linux/list.h:158 [inline]
list_add include/linux/list.h:177 [inline]
clone_mnt+0x447/0x9a0 fs/namespace.c:1286
copy_tree+0xde/0x930 fs/namespace.c:2170
copy_mnt_ns+0x11f/0x7c0 fs/namespace.c:4249
create_new_namespaces+0xcf/0x6a0 kernel/nsproxy.c:98
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3168
__do_sys_unshare kernel/fork.c:3239 [inline]
__se_sys_unshare kernel/fork.c:3237 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3237
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9df0f8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9def1f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f9df11e5fa0 RCX: 00007f9df0f8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002a060600
RBP: 00007f9df1013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9df11e6038 R14: 00007f9df11e5fa0 R15: 00007ffcc574ada8
</TASK>
Allocated by task 30875:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:5187 [inline]
slab_alloc_node mm/slub.c:5500 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5507
alloc_vfsmnt+0x23/0x420 fs/namespace.c:298
clone_mnt+0x4b/0x9a0 fs/namespace.c:1257
open_new_namespace fs/namespace.c:3110 [inline]
vfs_open_tree+0x4e8/0xf50 fs/namespace.c:3220
__do_sys_open_tree fs/namespace.c:3230 [inline]
__se_sys_open_tree fs/namespace.c:3228 [inline]
__x64_sys_open_tree+0x96/0x110 fs/namespace.c:3228
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 0:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2768 [inline]
slab_free mm/slub.c:6911 [inline]
kmem_cache_free+0x195/0x630 mm/slub.c:7022
rcu_do_batch kernel/rcu/tree.c:2617 [inline]
rcu_core+0x7bd/0x1060 kernel/rcu/tree.c:2869
handle_softirqs+0x22b/0x7c0 kernel/softirq.c:626
__do_softirq kernel/softirq.c:660 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x60/0x150 kernel/softirq.c:727
irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
Last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
__call_rcu_common kernel/rcu/tree.c:3131 [inline]
call_rcu+0xee/0x890 kernel/rcu/tree.c:3251
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Second to last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
task_work_add+0xb1/0x440 kernel/task_work.c:70
mntput_no_expire_slowpath+0x710/0xbe0 fs/namespace.c:1390
open_new_namespace fs/namespace.c:3175 [inline]
vfs_open_tree+0xd76/0xf50 fs/namespace.c:3220
__do_sys_open_tree fs/namespace.c:3230 [inline]
__se_sys_open_tree fs/namespace.c:3228 [inline]
__x64_sys_open_tree+0x96/0x110 fs/namespace.c:3228
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880747f4380
which belongs to the cache mnt_cache of size 352
The buggy address is located 192 bytes inside of
freed 352-byte region [ffff8880747f4380, ffff8880747f44e0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880747f4700 pfn:0x747f4
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880603d6f01
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801c2c1c80 ffffea0000e92100 dead000000000004
raw: ffff8880747f4700 0000000880120006 00000000f5000000 ffff8880603d6f01
head: 00fff00000000040 ffff88801c2c1c80 ffffea0000e92100 dead000000000004
head: ffff8880747f4700 0000000880120006 00000000f5000000 ffff8880603d6f01
head: 00fff00000000001 ffffea0001d1fd01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5822, tgid 5822 (syz-executor), ts 86866752041, free_ts 31783688525
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x23d/0x2a0 mm/page_alloc.c:1887
prep_new_page mm/page_alloc.c:1895 [inline]
get_page_from_freelist+0x23a5/0x2440 mm/page_alloc.c:3948
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5236
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
alloc_slab_page mm/slub.c:3303 [inline]
allocate_slab+0x87/0x670 mm/slub.c:3478
new_slab mm/slub.c:3536 [inline]
___slab_alloc+0xdb6/0x17b0 mm/slub.c:4890
__slab_alloc+0x65/0x100 mm/slub.c:5013
__slab_alloc_node mm/slub.c:5089 [inline]
slab_alloc_node mm/slub.c:5488 [inline]
kmem_cache_alloc_noprof+0x40f/0x710 mm/slub.c:5507
alloc_vfsmnt+0x23/0x420 fs/namespace.c:298
clone_mnt+0x4b/0x9a0 fs/namespace.c:1257
copy_tree+0x3d4/0x930 fs/namespace.c:2205
copy_mnt_ns+0x11f/0x7c0 fs/namespace.c:4249
create_new_namespaces+0xcf/0x6a0 kernel/nsproxy.c:98
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3168
__do_sys_unshare kernel/fork.c:3239 [inline]
__se_sys_unshare kernel/fork.c:3237 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3237
page last free pid 1 tgid 1 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1436 [inline]
__free_frozen_pages+0xb99/0xd10 mm/page_alloc.c:2976
__free_pages mm/page_alloc.c:5355 [inline]
free_contig_range+0x1bd/0x490 mm/page_alloc.c:7283
destroy_args+0x69/0x660 mm/debug_vm_pgtable.c:983
debug_vm_pgtable+0x38f/0x3a0 mm/debug_vm_pgtable.c:1372
do_one_initcall+0x1f1/0x800 init/main.c:1382
do_initcall_level+0x104/0x190 init/main.c:1444
do_initcalls+0x59/0xa0 init/main.c:1460
kernel_init_freeable+0x2a7/0x3e0 init/main.c:1692
kernel_init+0x1d/0x1d0 init/main.c:1582
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffff8880747f4300: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880747f4380: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880747f4400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880747f4480: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff8880747f4500: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================
---
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