==================================================================
BUG: KASAN: slab-out-of-bounds in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: slab-out-of-bounds in enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
Write of size 8 at addr ffff8881e5d831c8 by task syz.1.624/2470
CPU: 1 PID: 2470 Comm: syz.1.624 Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack+0x1e/0x20 lib/dump_stack.c:77
dump_stack+0x15b/0x1b8 lib/dump_stack.c:118
print_address_description+0x8d/0x4c0 mm/kasan/report.c:384
__kasan_report+0xef/0x120 mm/kasan/report.c:516
kasan_report+0x30/0x60 mm/kasan/common.c:653
__asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:137
hlist_add_head include/linux/list.h:814 [inline]
enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
__internal_add_timer kernel/time/timer.c:554 [inline]
internal_add_timer+0x208/0x3e0 kernel/time/timer.c:604
__mod_timer+0x5ab/0x1150 kernel/time/timer.c:1065
mod_timer+0x1f/0x30 kernel/time/timer.c:1117
can_stat_update+0xbab/0xc40 net/can/proc.c:186
call_timer_fn+0x3c/0x380 kernel/time/timer.c:1448
expire_timers kernel/time/timer.c:1493 [inline]
__run_timers+0x81d/0xb60 kernel/time/timer.c:1817
run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1830
__do_softirq+0x236/0x660 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x197/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:539 [inline]
smp_apic_timer_interrupt+0x11d/0x490 arch/x86/kernel/apic/apic.c:1161
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:46 [inline]
RIP: 0010:unwind_next_frame+0x32/0x760 arch/x86/kernel/unwind_frame.c:265
Code: 41 55 41 54 53 48 83 ec 58 48 89 fb 65 48 8b 04 25 28 00 00 00 48 89 45 d0 49 b8 00 00 00 00 00 fc ff df 49 89 fe 49 c1 ee 03 <43> 0f b6 04 06 84 c0 0f 85 4c 06 00 00 83 3b 00 0f 84 ad 05 00 00
RSP: 0018:ffff8881e71d7278 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13
RAX: eba3117212c40000 RBX: ffff8881e71d7308 RCX: 0000000000000002
RDX: ffff8881cad46e40 RSI: 0000000000000040 RDI: ffff8881e71d7308
RBP: ffff8881e71d72f8 R08: dffffc0000000000 R09: ffff8881e71d7308
R10: ffffed103ce3ae6d R11: 1ffff1103ce3ae61 R12: ffff8881cad46e40
R13: 1ffff1103ce3ae74 R14: 1ffff1103ce3ae61 R15: ffff8881e71d7308
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0xf0 kernel/stacktrace.c:123
save_stack mm/kasan/common.c:70 [inline]
set_track mm/kasan/common.c:78 [inline]
__kasan_kmalloc+0x162/0x200 mm/kasan/common.c:529
kasan_kmalloc+0xd/0x20 mm/kasan/common.c:543
__kmalloc+0x12a/0x2f0 mm/slub.c:3913
kmalloc include/linux/slab.h:561 [inline]
simple_xattr_alloc+0x3e/0xa0 fs/xattr.c:890
shmem_initxattrs+0x8d/0x1e0 mm/shmem.c:3164
security_inode_init_security+0x252/0x370 security/security.c:1009
shmem_mknod+0xbb/0x1c0 mm/shmem.c:2849
shmem_create+0x2b/0x40 mm/shmem.c:2904
lookup_open fs/namei.c:3379 [inline]
do_last fs/namei.c:3471 [inline]
path_openat+0x1603/0x35c0 fs/namei.c:3683
do_filp_open+0x1ae/0x3f0 fs/namei.c:3713
do_sys_open+0x2bb/0x5d0 fs/open.c:1123
__do_sys_openat fs/open.c:1150 [inline]
__se_sys_openat fs/open.c:1144 [inline]
__x64_sys_openat+0xa2/0xb0 fs/open.c:1144
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fa34551d969
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:00007fa343b86038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa345744fa0 RCX: 00007fa34551d969
RDX: 000000000000275a RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007fa34559fab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa345744fa0 R15: 00007ffe9b1fede8
Allocated by task 2363:
save_stack mm/kasan/common.c:70 [inline]
set_track mm/kasan/common.c:78 [inline]
__kasan_kmalloc+0x162/0x200 mm/kasan/common.c:529
kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537
slab_post_alloc_hook mm/slab.h:584 [inline]
slab_alloc_node mm/slub.c:2829 [inline]
slab_alloc mm/slub.c:2837 [inline]
__kmalloc_track_caller+0x10d/0x2d0 mm/slub.c:4449
__kmalloc_reserve net/core/skbuff.c:142 [inline]
pskb_expand_head+0x123/0x1110 net/core/skbuff.c:1653
skb_ensure_writable+0x2e7/0x460 net/core/skbuff.c:5569
__bpf_try_make_writable net/core/filter.c:1635 [inline]
bpf_try_make_writable net/core/filter.c:1641 [inline]
bpf_try_make_head_writable net/core/filter.c:1649 [inline]
____bpf_clone_redirect net/core/filter.c:2145 [inline]
bpf_clone_redirect+0x10b/0x380 net/core/filter.c:2123
0xffffffffa00b899f
bpf_call_func include/linux/filter.h:627 [inline]
bpf_test_run+0x1ea/0x5d0 net/bpf/test_run.c:44
bpf_prog_test_run_skb+0x721/0xdc0 net/bpf/test_run.c:311
bpf_prog_test_run+0x21a/0x2a0 kernel/bpf/syscall.c:2124
__do_sys_bpf kernel/bpf/syscall.c:2909 [inline]
__se_sys_bpf+0x49a/0x570 kernel/bpf/syscall.c:2849
__x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Freed by task 2363:
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+0x1c3/0x280 mm/kasan/common.c:487
kasan_slab_free+0xe/0x10 mm/kasan/common.c:496
slab_free_hook mm/slub.c:1455 [inline]
slab_free_freelist_hook+0xb7/0x180 mm/slub.c:1494
slab_free mm/slub.c:3080 [inline]
kfree+0xbe/0x260 mm/slub.c:4071
skb_free_head net/core/skbuff.c:601 [inline]
skb_release_data+0x4ea/0x610 net/core/skbuff.c:621
skb_release_all net/core/skbuff.c:675 [inline]
__kfree_skb net/core/skbuff.c:689 [inline]
kfree_skb+0xbc/0x3a0 net/core/skbuff.c:708
vti_tunnel_xmit+0x9df/0x12b0 net/ipv4/ip_vti.c:297
__netdev_start_xmit include/linux/netdevice.h:4544 [inline]
netdev_start_xmit include/linux/netdevice.h:4558 [inline]
xmit_one net/core/dev.c:3221 [inline]
dev_hard_start_xmit+0x1ef/0x6f0 net/core/dev.c:3237
__dev_queue_xmit+0x1228/0x2400 net/core/dev.c:3821
dev_queue_xmit+0x17/0x20 net/core/dev.c:3854
__bpf_tx_skb net/core/filter.c:2063 [inline]
__bpf_redirect_no_mac net/core/filter.c:2097 [inline]
__bpf_redirect+0x699/0xe30 net/core/filter.c:2120
____bpf_clone_redirect net/core/filter.c:2151 [inline]
bpf_clone_redirect+0x242/0x380 net/core/filter.c:2123
0xffffffffa00b899f
bpf_call_func include/linux/filter.h:627 [inline]
bpf_test_run+0x1ea/0x5d0 net/bpf/test_run.c:44
bpf_prog_test_run_skb+0x721/0xdc0 net/bpf/test_run.c:311
bpf_prog_test_run+0x21a/0x2a0 kernel/bpf/syscall.c:2124
__do_sys_bpf kernel/bpf/syscall.c:2909 [inline]
__se_sys_bpf+0x49a/0x570 kernel/bpf/syscall.c:2849
__x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
The buggy address belongs to the object at ffff8881e5d82000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 456 bytes to the right of
4096-byte region [ffff8881e5d82000, ffff8881e5d83000)
The buggy address belongs to the page:
page:ffffea0007976000 refcount:1 mapcount:0 mapping:ffff8881f5c0c280 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c0c280
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__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+0x35e/0x370 mm/page_alloc.c:2171
get_page_from_freelist+0x1296/0x1310 mm/page_alloc.c:3794
__alloc_pages_nodemask+0x202/0x4b0 mm/page_alloc.c:4894
alloc_slab_page+0x3c/0x3b0 mm/slub.c:343
allocate_slab mm/slub.c:1683 [inline]
new_slab+0x93/0x420 mm/slub.c:1749
new_slab_objects mm/slub.c:2505 [inline]
___slab_alloc+0x29e/0x420 mm/slub.c:2667
__slab_alloc+0x63/0xa0 mm/slub.c:2707
slab_alloc_node mm/slub.c:2792 [inline]
slab_alloc mm/slub.c:2837 [inline]
__kmalloc_track_caller+0x17c/0x2d0 mm/slub.c:4449
__kmalloc_reserve net/core/skbuff.c:142 [inline]
pskb_expand_head+0x123/0x1110 net/core/skbuff.c:1653
skb_ensure_writable+0x2e7/0x460 net/core/skbuff.c:5569
__bpf_try_make_writable net/core/filter.c:1635 [inline]
bpf_try_make_writable net/core/filter.c:1641 [inline]
bpf_try_make_head_writable net/core/filter.c:1649 [inline]
____bpf_clone_redirect net/core/filter.c:2145 [inline]
bpf_clone_redirect+0x10b/0x380 net/core/filter.c:2123
0xffffffffa00b899f
bpf_call_func include/linux/filter.h:627 [inline]
bpf_test_run+0x1ea/0x5d0 net/bpf/test_run.c:44
bpf_prog_test_run_skb+0x721/0xdc0 net/bpf/test_run.c:311
bpf_prog_test_run+0x21a/0x2a0 kernel/bpf/syscall.c:2124
__do_sys_bpf kernel/bpf/syscall.c:2909 [inline]
__se_sys_bpf+0x49a/0x570 kernel/bpf/syscall.c:2849
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+0x7e4/0x910 mm/page_alloc.c:1438
free_the_page mm/page_alloc.c:4956 [inline]
__free_pages+0x8c/0x110 mm/page_alloc.c:4962
kfree+0x1ca/0x260 mm/slub.c:4068
kvfree+0x4c/0x50 mm/util.c:625
bpf_check+0x8371/0x9cf0 kernel/bpf/verifier.c:9731
bpf_prog_load+0xa5f/0xe10 kernel/bpf/syscall.c:1724
__do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
__se_sys_bpf+0x435/0x570 kernel/bpf/syscall.c:2849
__x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Memory state around the buggy address:
ffff8881e5d83080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881e5d83100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881e5d83180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8881e5d83200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8881e5d83280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1e8392067 P4D 1e8392067 PUD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 2470 Comm: syz.1.624 Tainted: G B 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09cf0 EFLAGS: 00010206
RAX: ffffffff8150a590 RBX: 0000000000000100 RCX: ffff8881cad46e40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881e5d831c0
RBP: ffff8881f6f09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103ede1398 R11: 1ffff1103ede1398 R12: 00000000ffffa758
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e5d831c0
FS: 00007fa343b866c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001e8180000 CR4: 00000000003406a0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
call_timer_fn+0x3c/0x380 kernel/time/timer.c:1448
expire_timers kernel/time/timer.c:1493 [inline]
__run_timers+0x81d/0xb60 kernel/time/timer.c:1817
run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1830
__do_softirq+0x236/0x660 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x197/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:539 [inline]
smp_apic_timer_interrupt+0x11d/0x490 arch/x86/kernel/apic/apic.c:1161
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:46 [inline]
RIP: 0010:unwind_next_frame+0x32/0x760 arch/x86/kernel/unwind_frame.c:265
Code: 41 55 41 54 53 48 83 ec 58 48 89 fb 65 48 8b 04 25 28 00 00 00 48 89 45 d0 49 b8 00 00 00 00 00 fc ff df 49 89 fe 49 c1 ee 03 <43> 0f b6 04 06 84 c0 0f 85 4c 06 00 00 83 3b 00 0f 84 ad 05 00 00
RSP: 0018:ffff8881e71d7278 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13
RAX: eba3117212c40000 RBX: ffff8881e71d7308 RCX: 0000000000000002
RDX: ffff8881cad46e40 RSI: 0000000000000040 RDI: ffff8881e71d7308
RBP: ffff8881e71d72f8 R08: dffffc0000000000 R09: ffff8881e71d7308
R10: ffffed103ce3ae6d R11: 1ffff1103ce3ae61 R12: ffff8881cad46e40
R13: 1ffff1103ce3ae74 R14: 1ffff1103ce3ae61 R15: ffff8881e71d7308
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0xf0 kernel/stacktrace.c:123
save_stack mm/kasan/common.c:70 [inline]
set_track mm/kasan/common.c:78 [inline]
__kasan_kmalloc+0x162/0x200 mm/kasan/common.c:529
kasan_kmalloc+0xd/0x20 mm/kasan/common.c:543
__kmalloc+0x12a/0x2f0 mm/slub.c:3913
kmalloc include/linux/slab.h:561 [inline]
simple_xattr_alloc+0x3e/0xa0 fs/xattr.c:890
shmem_initxattrs+0x8d/0x1e0 mm/shmem.c:3164
security_inode_init_security+0x252/0x370 security/security.c:1009
shmem_mknod+0xbb/0x1c0 mm/shmem.c:2849
shmem_create+0x2b/0x40 mm/shmem.c:2904
lookup_open fs/namei.c:3379 [inline]
do_last fs/namei.c:3471 [inline]
path_openat+0x1603/0x35c0 fs/namei.c:3683
do_filp_open+0x1ae/0x3f0 fs/namei.c:3713
do_sys_open+0x2bb/0x5d0 fs/open.c:1123
__do_sys_openat fs/open.c:1150 [inline]
__se_sys_openat fs/open.c:1144 [inline]
__x64_sys_openat+0xa2/0xb0 fs/open.c:1144
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fa34551d969
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:00007fa343b86038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa345744fa0 RCX: 00007fa34551d969
RDX: 000000000000275a RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007fa34559fab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa345744fa0 R15: 00007ffe9b1fede8
Modules linked in:
CR2: 0000000000000000
---[ end trace b553735991ac98bd ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09cf0 EFLAGS: 00010206
RAX: ffffffff8150a590 RBX: 0000000000000100 RCX: ffff8881cad46e40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881e5d831c0
RBP: ffff8881f6f09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103ede1398 R11: 1ffff1103ede1398 R12: 00000000ffffa758
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e5d831c0
FS: 00007fa343b866c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001e8180000 CR4: 00000000003406a0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
0: 41 55 push %r13
2: 41 54 push %r12
4: 53 push %rbx
5: 48 83 ec 58 sub $0x58,%rsp
9: 48 89 fb mov %rdi,%rbx
c: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax
13: 00 00
15: 48 89 45 d0 mov %rax,-0x30(%rbp)
19: 49 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%r8
20: fc ff df
23: 49 89 fe mov %rdi,%r14
26: 49 c1 ee 03 shr $0x3,%r14
* 2a: 43 0f b6 04 06 movzbl (%r14,%r8,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 0f 85 4c 06 00 00 jne 0x683
37: 83 3b 00 cmpl $0x0,(%rbx)
3a: 0f 84 ad 05 00 00 je 0x5ed