==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
Write of size 8 at addr ffff8881e7a8f1c8 by task syz.2.46/547
CPU: 1 PID: 547 Comm: syz.2.46 Not tainted 5.4.290-syzkaller-00017-g6b07fcd94a6a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d8/0x241 lib/dump_stack.c:118
print_address_description+0x8c/0x600 mm/kasan/report.c:384
__kasan_report+0xf3/0x120 mm/kasan/report.c:516
kasan_report+0x30/0x60 mm/kasan/common.c:653
hlist_add_head include/linux/list.h:814 [inline]
enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
__internal_add_timer kernel/time/timer.c:554 [inline]
internal_add_timer+0x240/0x430 kernel/time/timer.c:604
__mod_timer+0x6f1/0x13e0 kernel/time/timer.c:1065
call_timer_fn+0x36/0x390 kernel/time/timer.c:1448
expire_timers kernel/time/timer.c:1493 [inline]
__run_timers+0x879/0xbe0 kernel/time/timer.c:1817
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830
__do_softirq+0x23b/0x6b7 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x195/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:539 [inline]
smp_apic_timer_interrupt+0x11a/0x490 arch/x86/kernel/apic/apic.c:1161
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
RIP: 0010:zap_pte_range mm/memory.c:1155 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1222 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1251 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1272 [inline]
RIP: 0010:unmap_page_range+0xb25/0x2620 mm/memory.c:1293
Code: 79 03 00 49 89 dd eb 43 e8 e8 71 d9 ff 4c 8b 74 24 08 4c 8b 6c 24 20 48 8b 5c 24 10 4c 39 b4 24 58 01 00 00 0f 84 c6 0b 00 00 <4c> 8b ac 24 98 00 00 00 49 83 c5 08 e8 ba 71 d9 ff 48 83 c3 08 49
RSP: 0018:ffff8881e6f9f5a0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: ffffffff818adfd0 RBX: ffff8881e82daf08 RCX: ffff8881e7568fc0
RDX: 0000000000000000 RSI: 00000000000001fe RDI: 0000000000000028
RBP: ffff8881e6f9f790 R08: ffffffff818d6489 R09: fffff94000ee173f
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881eaeed300 R14: 00007f3aa93e1000 R15: ffffea000770b9c0
unmap_single_vma mm/memory.c:1338 [inline]
unmap_vmas+0x355/0x4b0 mm/memory.c:1370
exit_mmap+0x2bc/0x520 mm/mmap.c:3191
__mmput+0x8e/0x2c0 kernel/fork.c:1101
exit_mm kernel/exit.c:538 [inline]
do_exit+0xc08/0x2bc0 kernel/exit.c:848
do_group_exit+0x138/0x300 kernel/exit.c:984
get_signal+0xdb1/0x1440 kernel/signal.c:2738
do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809
exit_to_usermode_loop+0xc0/0x1a0 arch/x86/entry/common.c:159
prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f3aaa13f169
Code: Bad RIP value.
RSP: 002b:00007f3aa87a9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffff9f RBX: 00007f3aaa357fa0 RCX: 00007f3aaa13f169
RDX: 00000000fffffffc RSI: 0000000000000000 RDI: 0000000000000021
RBP: 00007f3aaa1c02a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000400000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3aaa357fa0 R15: 00007ffd942ba528
Allocated by task 354:
save_stack mm/kasan/common.c:70 [inline]
set_track mm/kasan/common.c:78 [inline]
__kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529
slab_post_alloc_hook mm/slab.h:584 [inline]
slab_alloc_node mm/slub.c:2829 [inline]
slab_alloc mm/slub.c:2837 [inline]
kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842
shmem_alloc_inode+0x16/0x30 mm/shmem.c:3719
alloc_inode fs/inode.c:231 [inline]
new_inode_pseudo+0x60/0x210 fs/inode.c:966
new_inode+0x25/0x1d0 fs/inode.c:995
shmem_get_inode+0x10b/0x620 mm/shmem.c:2252
shmem_mknod+0x54/0x1a0 mm/shmem.c:2844
lookup_open fs/namei.c:3379 [inline]
do_last fs/namei.c:3471 [inline]
path_openat+0x184a/0x34b0 fs/namei.c:3683
do_filp_open+0x20b/0x450 fs/namei.c:3713
do_sys_open+0x39c/0x810 fs/open.c:1123
do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Freed by task 10:
save_stack mm/kasan/common.c:70 [inline]
set_track mm/kasan/common.c:78 [inline]
kasan_set_free_info mm/kasan/common.c:345 [inline]
__kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
slab_free_hook mm/slub.c:1455 [inline]
slab_free_freelist_hook mm/slub.c:1494 [inline]
slab_free mm/slub.c:3080 [inline]
kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096
__rcu_reclaim kernel/rcu/rcu.h:222 [inline]
rcu_do_batch+0x492/0xa00 kernel/rcu/tree.c:2167
rcu_core+0x4c8/0xcb0 kernel/rcu/tree.c:2387
__do_softirq+0x23b/0x6b7 kernel/softirq.c:292
The buggy address belongs to the object at ffff8881e7a8f090
which belongs to the cache shmem_inode_cache of size 760
The buggy address is located 312 bytes inside of
760-byte region [ffff8881e7a8f090, ffff8881e7a8f388)
The buggy address belongs to the page:
page:ffffea00079ea300 refcount:1 mapcount:0 mapping:ffff8881f5cfea00 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5cfea00
raw: 0000000000000000 0000000000120012 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL)
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook mm/page_alloc.c:2165 [inline]
prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
__alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893
alloc_slab_page+0x39/0x3c0 mm/slub.c:343
allocate_slab mm/slub.c:1683 [inline]
new_slab+0x97/0x440 mm/slub.c:1749
new_slab_objects mm/slub.c:2505 [inline]
___slab_alloc+0x2fe/0x490 mm/slub.c:2667
__slab_alloc+0x62/0xa0 mm/slub.c:2707
slab_alloc_node mm/slub.c:2792 [inline]
slab_alloc mm/slub.c:2837 [inline]
kmem_cache_alloc+0x109/0x250 mm/slub.c:2842
shmem_alloc_inode+0x16/0x30 mm/shmem.c:3719
alloc_inode fs/inode.c:231 [inline]
new_inode_pseudo+0x60/0x210 fs/inode.c:966
new_inode+0x25/0x1d0 fs/inode.c:995
shmem_get_inode+0x10b/0x620 mm/shmem.c:2252
shmem_symlink+0x118/0x5f0 mm/shmem.c:3068
vfs_symlink+0x36c/0x500 fs/namei.c:4276
do_symlinkat+0x19b/0x400 fs/namei.c:4303
do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1176 [inline]
__free_pages_ok+0x847/0x950 mm/page_alloc.c:1438
free_the_page mm/page_alloc.c:4955 [inline]
__free_pages+0x91/0x140 mm/page_alloc.c:4961
bpf_check+0x8aeb/0xb3e0 kernel/bpf/verifier.c:9731
bpf_prog_load kernel/bpf/syscall.c:1724 [inline]
__do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
__se_sys_bpf+0x8139/0xbcb0 kernel/bpf/syscall.c:2849
do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Memory state around the buggy address:
ffff8881e7a8f080: fc fc fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881e7a8f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881e7a8f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8881e7a8f200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881e7a8f280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 0 P4D 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 547 Comm: syz.2.46 Tainted: G B 5.4.290-syzkaller-00017-g6b07fcd94a6a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010002
RAX: ffffffff8154e8ca RBX: 0000000000000102 RCX: ffff8881e7568fc0
RDX: 0000000080000102 RSI: 0000000000000000 RDI: ffff8881e7a8f1c0
RBP: ffff8881f6f09ec8 R08: ffffffff8154e50e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff98e8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e7a8f1c0
FS: 00007f3aa87a96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001ecec8000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
call_timer_fn+0x36/0x390 kernel/time/timer.c:1448
expire_timers kernel/time/timer.c:1488 [inline]
__run_timers+0x8a5/0xbe0 kernel/time/timer.c:1817
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830
__do_softirq+0x23b/0x6b7 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x195/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:539 [inline]
smp_apic_timer_interrupt+0x11a/0x490 arch/x86/kernel/apic/apic.c:1161
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x45/0x60 kernel/locking/spinlock.c:199
Code: 08 00 74 0c 48 c7 c7 90 3c eb 85 e8 55 03 3d fd 48 83 3d ad 0a 94 01 00 74 29 48 89 df e8 a3 d5 f4 fc 66 90 fb bf 01 00 00 00 d6 bf ed fc 65 8b 05 8b 5b ab 7b 85 c0 74 02 5b c3 e8 14 22 a9
RSP: 0018:ffff8881e6f9f370 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffff8881f6f57b40 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffff8881e6f9f470 R08: dffffc0000000000 R09: ffffed103cead1f9
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881e7568fc0 R14: ffff8881e7568fc0 R15: ffff8881e7569038
rq_unlock_irq kernel/sched/sched.h:1270 [inline]
__schedule+0xcff/0x1320 kernel/sched/core.c:4310
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:4456
preempt_schedule+0xd9/0xe0 kernel/sched/core.c:4481
___preempt_schedule+0x16/0x20 arch/x86/entry/thunk_64.S:50
__raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock+0x5b/0x60 kernel/locking/spinlock.c:183
spin_unlock include/linux/spinlock.h:378 [inline]
zap_pte_range mm/memory.c:1163 [inline]
zap_pmd_range mm/memory.c:1222 [inline]
zap_pud_range mm/memory.c:1251 [inline]
zap_p4d_range mm/memory.c:1272 [inline]
unmap_page_range+0xa07/0x2620 mm/memory.c:1293
unmap_single_vma mm/memory.c:1338 [inline]
unmap_vmas+0x355/0x4b0 mm/memory.c:1370
exit_mmap+0x2bc/0x520 mm/mmap.c:3191
__mmput+0x8e/0x2c0 kernel/fork.c:1101
exit_mm kernel/exit.c:538 [inline]
do_exit+0xc08/0x2bc0 kernel/exit.c:848
do_group_exit+0x138/0x300 kernel/exit.c:984
get_signal+0xdb1/0x1440 kernel/signal.c:2738
do_signal+0xb0/0x11f0 arch/x86/kernel/signal.c:809
exit_to_usermode_loop+0xc0/0x1a0 arch/x86/entry/common.c:159
prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f3aaa13f169
Code: Bad RIP value.
RSP: 002b:00007f3aa87a9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffff9f RBX: 00007f3aaa357fa0 RCX: 00007f3aaa13f169
RDX: 00000000fffffffc RSI: 0000000000000000 RDI: 0000000000000021
RBP: 00007f3aaa1c02a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000400000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3aaa357fa0 R15: 00007ffd942ba528
Modules linked in:
CR2: 0000000000000000
---[ end trace 77cbdf1cff437e77 ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010002
RAX: ffffffff8154e8ca RBX: 0000000000000102 RCX: ffff8881e7568fc0
RDX: 0000000080000102 RSI: 0000000000000000 RDI: ffff8881e7a8f1c0
RBP: ffff8881f6f09ec8 R08: ffffffff8154e50e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff98e8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e7a8f1c0
FS: 00007f3aa87a96c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001ecec8000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 79 03 jns 0x5
2: 00 49 89 add %cl,-0x77(%rcx)
5: dd eb fucomp %st(3)
7: 43 e8 e8 71 d9 ff rex.XB call 0xffd971f5
d: 4c 8b 74 24 08 mov 0x8(%rsp),%r14
12: 4c 8b 6c 24 20 mov 0x20(%rsp),%r13
17: 48 8b 5c 24 10 mov 0x10(%rsp),%rbx
1c: 4c 39 b4 24 58 01 00 cmp %r14,0x158(%rsp)
23: 00
24: 0f 84 c6 0b 00 00 je 0xbf0
* 2a: 4c 8b ac 24 98 00 00 mov 0x98(%rsp),%r13 <-- trapping instruction
31: 00
32: 49 83 c5 08 add $0x8,%r13
36: e8 ba 71 d9 ff call 0xffd971f5
3b: 48 83 c3 08 add $0x8,%rbx
3f: 49 rex.WB