==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
Write of size 8 at addr ffff8881e367b1c8 by task syz.2.824/3523
CPU: 1 PID: 3523 Comm: syz.2.824 Tainted: G W 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
do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1086
do_softirq+0xf9/0x140 kernel/softirq.c:337
__local_bh_enable_ip+0x70/0x80 kernel/softirq.c:189
local_bh_enable+0x1f/0x30 include/linux/bottom_half.h:32
rcu_read_unlock_bh include/linux/rcupdate.h:739 [inline]
__dev_queue_xmit+0x136e/0x2400 net/core/dev.c:3848
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
bpf_prog_973cd02a7a0e8181+0x1a8/0x1000
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
RIP: 0033:0x7fcea0033969
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:00007fce9e69c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fcea025afa0 RCX: 00007fcea0033969
RDX: 000000000000002c RSI: 0000200000000080 RDI: 000000000000000a
RBP: 00007fcea00b5ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcea025afa0 R15: 00007ffd17a51778
The buggy address belongs to the page:
page:ffffea00078d9ec0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 ffffea000795b008 ffffea00078d9e88 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO)
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_pages include/linux/gfp.h:503 [inline]
__alloc_pages_node include/linux/gfp.h:516 [inline]
alloc_pages_node include/linux/gfp.h:530 [inline]
__vmalloc_area_node mm/vmalloc.c:-1 [inline]
__vmalloc_node_range+0x36a/0x6e0 mm/vmalloc.c:2499
vmalloc_user+0x73/0x80 mm/vmalloc.c:2629
kcov_mmap+0x2b/0x120 kernel/kcov.c:450
call_mmap include/linux/fs.h:1996 [inline]
mmap_region+0x101b/0x15a0 mm/mmap.c:1812
do_mmap+0x826/0xd90 mm/mmap.c:1581
do_mmap_pgoff include/linux/mm.h:2480 [inline]
vm_mmap_pgoff+0x195/0x230 mm/util.c:528
ksys_mmap_pgoff+0x16f/0x1e0 mm/mmap.c:1631
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:97 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:88 [inline]
__x64_sys_mmap+0xfa/0x110 arch/x86/kernel/sys_x86_64.c:88
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
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_pcp_prepare mm/page_alloc.c:1233 [inline]
free_unref_page_prepare+0x2a9/0x3a0 mm/page_alloc.c:3085
free_unref_page mm/page_alloc.c:3134 [inline]
free_the_page mm/page_alloc.c:4954 [inline]
__free_pages+0xaa/0x110 mm/page_alloc.c:4962
__vunmap+0x76a/0x8a0 mm/vmalloc.c:2260
__vfree mm/vmalloc.c:2308 [inline]
vfree+0x61/0x90 mm/vmalloc.c:2338
kcov_mmap+0x8c/0x120 kernel/kcov.c:474
call_mmap include/linux/fs.h:1996 [inline]
mmap_region+0x101b/0x15a0 mm/mmap.c:1812
do_mmap+0x826/0xd90 mm/mmap.c:1581
do_mmap_pgoff include/linux/mm.h:2480 [inline]
vm_mmap_pgoff+0x195/0x230 mm/util.c:528
ksys_mmap_pgoff+0x16f/0x1e0 mm/mmap.c:1631
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:97 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:88 [inline]
__x64_sys_mmap+0xfa/0x110 arch/x86/kernel/sys_x86_64.c:88
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Memory state around the buggy address:
ffff8881e367b080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881e367b100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e367b180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881e367b200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881e367b280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
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: 0 Comm: swapper/1 Tainted: G B W 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: 00010202
RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881f5dc3f00
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881e367b1c0
RBP: ffff8881f6f09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103ede1398 R11: 1ffff1103ede1398 R12: 00000000ffffb698
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e367b1c0
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001de7fd000 CR4: 00000000003406a0
DR0: 0000200000000300 DR1: 0000200000000300 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:default_idle+0x23/0x40 arch/x86/kernel/process.c:578
Code: 90 90 00 00 90 90 00 55 48 89 e5 e8 87 b2 f5 fd bf 01 00 00 00 89 c6 e8 bb 1c fc fc 0f 1f 44 00 00 0f 00 2d cf c2 59 00 fb f4 68 b2 f5 fd bf ff ff ff ff 89 c6 e8 9c 1c fc fc 5d c3 66 2e 0f
RSP: 0018:ffff8881f5df7d80 EFLAGS: 000002c6 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffff8881f5dc3f00 RCX: ffff8881f5dc3f00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffff8881f5df7d80 R08: dffffc0000000000 R09: ffffed103ebb87e1
R10: ffffed103ebb87e1 R11: 1ffff1103ebb87e0 R12: 0000000000000001
R13: 1ffff1103ebb87e0 R14: 0000000000000000 R15: ffffffff862bb528
arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:568
default_idle_call kernel/sched/idle.c:94 [inline]
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x21d/0x550 kernel/sched/idle.c:264
cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:356
start_secondary+0x366/0x420 arch/x86/kernel/smpboot.c:277
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
Modules linked in:
CR2: 0000000000000000
---[ end trace 7964e0453507a112 ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09cf0 EFLAGS: 00010202
RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881f5dc3f00
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881e367b1c0
RBP: ffff8881f6f09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103ede1398 R11: 1ffff1103ede1398 R12: 00000000ffffb698
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e367b1c0
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001de7fd000 CR4: 00000000003406a0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 00 00 add %al,(%rax)
4: 90 nop
5: 90 nop
6: 00 55 48 add %dl,0x48(%rbp)
9: 89 e5 mov %esp,%ebp
b: e8 87 b2 f5 fd call 0xfdf5b297
10: bf 01 00 00 00 mov $0x1,%edi
15: 89 c6 mov %eax,%esi
17: e8 bb 1c fc fc call 0xfcfc1cd7
1c: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
21: 0f 00 2d cf c2 59 00 verw 0x59c2cf(%rip) # 0x59c2f7
28: fb sti
29: f4 hlt
* 2a: e8 68 b2 f5 fd call 0xfdf5b297 <-- trapping instruction
2f: bf ff ff ff ff mov $0xffffffff,%edi
34: 89 c6 mov %eax,%esi
36: e8 9c 1c fc fc call 0xfcfc1cd7
3b: 5d pop %rbp
3c: c3 ret
3d: 66 data16
3e: 2e cs
3f: 0f .byte 0xf