==================================================================
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+0xb7/0x300 kernel/time/timer.c:541
Write of size 8 at addr ffff8881c770b1c8 by task syz.6.398/2018

CPU: 1 PID: 2018 Comm: syz.6.398 Not tainted 5.4.290-syzkaller-00002-g41adfeb3d639 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <IRQ>
 __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
 </IRQ>
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:207 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x70 kernel/kcov.c:274
Code: 77 cf 89 f8 89 f6 48 c7 44 0a 08 03 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 c3 90 4c 8b 04 24 <65> 48 8b 05 84 3f 9e 7e 65 8b 0d 89 3f 9e 7e f7 c1 00 01 1f 00 74
RSP: 0018:ffff8881cf8deed8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffffff818f15ab RCX: 0000000000000000
RDX: ffff8881dffe9f80 RSI: 0000000000000008 RDI: 0000000000000003
RBP: ffff8881cf8df020 R08: ffffffff8198ac4b R09: ffffed103edeb135
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8198a97f
R13: 0000000000000008 R14: dffffc0000000000 R15: 1ffff11039f1bde0
 check_recursive_alloc mm/page_owner.c:109 [inline]
 save_stack+0x1eb/0x880 mm/page_owner.c:132
 __reset_page_owner+0x1f/0x100 mm/page_owner.c:149
 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+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page mm/page_alloc.c:3134 [inline]
 free_the_page mm/page_alloc.c:4953 [inline]
 __free_pages+0xaf/0x140 mm/page_alloc.c:4961
 __vunmap+0x75b/0x890 mm/vmalloc.c:2260
 bpf_prog_calc_tag+0x697/0x8f0 kernel/bpf/core.c:336
 replace_map_fd_with_map_ptr kernel/bpf/verifier.c:8218 [inline]
 bpf_check+0x91a/0xb3e0 kernel/bpf/verifier.c:9608
 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
RIP: 0033:0x7fc775c04169
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:00007fc77424d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fc775e1d080 RCX: 00007fc775c04169
RDX: 0000000000000070 RSI: 0000200000000440 RDI: 0000000000000005
RBP: 00007fc775c852a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc775e1d080 R15: 00007ffeb31556d8

Allocated by task 1999:
 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
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kvmalloc_node+0x7e/0xf0 mm/util.c:596
 kvmalloc include/linux/mm.h:761 [inline]
 kvmalloc_array include/linux/mm.h:779 [inline]
 __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:470 [inline]
 ptr_ring_init include/linux/ptr_ring.h:488 [inline]
 skb_array_init include/linux/skb_array.h:182 [inline]
 pfifo_fast_init+0x377/0x760 net/sched/sch_generic.c:784
 qdisc_create_dflt+0x129/0x250 net/sched/sch_generic.c:944
 mq_init+0x2c8/0x6b0 net/sched/sch_mq.c:90
 qdisc_create_dflt+0x129/0x250 net/sched/sch_generic.c:944
 attach_default_qdiscs net/sched/sch_generic.c:1113 [inline]
 dev_activate+0x11f/0xc00 net/sched/sch_generic.c:1154
 __dev_open+0x302/0x420 net/core/dev.c:1335
 __dev_change_flags+0x1db/0x6e0 net/core/dev.c:7958
 dev_change_flags+0x87/0x190 net/core/dev.c:8029
 dev_ifsioc+0x104/0xa60 net/core/dev_ioctl.c:226
 dev_ioctl+0x505/0xb40 net/core/dev_ioctl.c:483
 sock_do_ioctl+0x295/0x3a0 net/socket.c:1081
 sock_ioctl+0x4a4/0x760 net/socket.c:1198
 do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
 ksys_ioctl fs/ioctl.c:742 [inline]
 __do_sys_ioctl fs/ioctl.c:749 [inline]
 __se_sys_ioctl fs/ioctl.c:747 [inline]
 __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8881c770a000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 456 bytes to the right of
 4096-byte region [ffff8881c770a000, ffff8881c770b000)
The buggy address belongs to the page:
page:ffffea00071dc200 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 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]
 __kmalloc+0x19b/0x2e0 mm/slub.c:3909
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kvmalloc_node+0x7e/0xf0 mm/util.c:596
 kvmalloc include/linux/mm.h:761 [inline]
 kvmalloc_array include/linux/mm.h:779 [inline]
 __ptr_ring_init_queue_alloc include/linux/ptr_ring.h:470 [inline]
 ptr_ring_init include/linux/ptr_ring.h:488 [inline]
 skb_array_init include/linux/skb_array.h:182 [inline]
 pfifo_fast_init+0x377/0x760 net/sched/sch_generic.c:784
 qdisc_create_dflt+0x129/0x250 net/sched/sch_generic.c:944
 mq_init+0x2c8/0x6b0 net/sched/sch_mq.c:90
 qdisc_create_dflt+0x129/0x250 net/sched/sch_generic.c:944
 attach_default_qdiscs net/sched/sch_generic.c:1113 [inline]
 dev_activate+0x11f/0xc00 net/sched/sch_generic.c:1154
 __dev_open+0x302/0x420 net/core/dev.c:1335
 __dev_change_flags+0x1db/0x6e0 net/core/dev.c:7958
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+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page mm/page_alloc.c:3134 [inline]
 free_the_page mm/page_alloc.c:4953 [inline]
 __free_pages+0xaf/0x140 mm/page_alloc.c:4961
 __vunmap+0x75b/0x890 mm/vmalloc.c:2260
 kcov_mmap+0x8c/0x120 kernel/kcov.c:474
 call_mmap include/linux/fs.h:1996 [inline]
 mmap_region+0x110d/0x16f0 mm/mmap.c:1812
 do_mmap+0x822/0xd30 mm/mmap.c:1581
 do_mmap_pgoff include/linux/mm.h:2480 [inline]
 vm_mmap_pgoff+0x1b5/0x260 mm/util.c:528
 ksys_mmap_pgoff+0x168/0x1e0 mm/mmap.c:1631
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881c770b080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881c770b100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881c770b180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                              ^
 ffff8881c770b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881c770b280: 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 1d1f4d067 P4D 1d1f4d067 PUD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 2018 Comm: syz.6.398 Tainted: G    B             5.4.290-syzkaller-00002-g41adfeb3d639 #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: 00010206
RAX: ffffffff8154e8ca RBX: 0000000000000100 RCX: ffff8881dffe9f80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881c770b1c0
RBP: ffff8881f6f09ec8 R08: ffffffff8154e50e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffffb180
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881c770b1c0
FS:  00007fc77424d6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001cc65d000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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
 </IRQ>
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:207 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x70 kernel/kcov.c:274
Code: 77 cf 89 f8 89 f6 48 c7 44 0a 08 03 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 49 ff c1 4c 89 09 c3 90 4c 8b 04 24 <65> 48 8b 05 84 3f 9e 7e 65 8b 0d 89 3f 9e 7e f7 c1 00 01 1f 00 74
RSP: 0018:ffff8881cf8deed8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffffff818f15ab RCX: 0000000000000000
RDX: ffff8881dffe9f80 RSI: 0000000000000008 RDI: 0000000000000003
RBP: ffff8881cf8df020 R08: ffffffff8198ac4b R09: ffffed103edeb135
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8198a97f
R13: 0000000000000008 R14: dffffc0000000000 R15: 1ffff11039f1bde0
 check_recursive_alloc mm/page_owner.c:109 [inline]
 save_stack+0x1eb/0x880 mm/page_owner.c:132
 __reset_page_owner+0x1f/0x100 mm/page_owner.c:149
 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+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page mm/page_alloc.c:3134 [inline]
 free_the_page mm/page_alloc.c:4953 [inline]
 __free_pages+0xaf/0x140 mm/page_alloc.c:4961
 __vunmap+0x75b/0x890 mm/vmalloc.c:2260
 bpf_prog_calc_tag+0x697/0x8f0 kernel/bpf/core.c:336
 replace_map_fd_with_map_ptr kernel/bpf/verifier.c:8218 [inline]
 bpf_check+0x91a/0xb3e0 kernel/bpf/verifier.c:9608
 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
RIP: 0033:0x7fc775c04169
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:00007fc77424d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fc775e1d080 RCX: 00007fc775c04169
RDX: 0000000000000070 RSI: 0000200000000440 RDI: 0000000000000005
RBP: 00007fc775c852a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fc775e1d080 R15: 00007ffeb31556d8
Modules linked in:
CR2: 0000000000000000
---[ end trace e84565d446c6d4c2 ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010206
RAX: ffffffff8154e8ca RBX: 0000000000000100 RCX: ffff8881dffe9f80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881c770b1c0
RBP: ffff8881f6f09ec8 R08: ffffffff8154e50e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffffb180
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881c770b1c0
FS:  00007fc77424d6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001cc65d000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
   0:	77 cf                	ja     0xffffffd1
   2:	89 f8                	mov    %edi,%eax
   4:	89 f6                	mov    %esi,%esi
   6:	48 c7 44 0a 08 03 00 	movq   $0x3,0x8(%rdx,%rcx,1)
   d:	00 00
   f:	48 89 44 0a 10       	mov    %rax,0x10(%rdx,%rcx,1)
  14:	48 89 74 0a 18       	mov    %rsi,0x18(%rdx,%rcx,1)
  19:	4c 89 44 0a 20       	mov    %r8,0x20(%rdx,%rcx,1)
  1e:	49 ff c1             	inc    %r9
  21:	4c 89 09             	mov    %r9,(%rcx)
  24:	c3                   	ret
  25:	90                   	nop
  26:	4c 8b 04 24          	mov    (%rsp),%r8
* 2a:	65 48 8b 05 84 3f 9e 	mov    %gs:0x7e9e3f84(%rip),%rax        # 0x7e9e3fb6 <-- trapping instruction
  31:	7e
  32:	65 8b 0d 89 3f 9e 7e 	mov    %gs:0x7e9e3f89(%rip),%ecx        # 0x7e9e3fc2
  39:	f7 c1 00 01 1f 00    	test   $0x1f0100,%ecx
  3f:	74                   	.byte 0x74