================================================================== 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 ffff8881e8d4b1c8 by task syz-executor.1/573 CPU: 1 PID: 573 Comm: syz-executor.1 Not tainted 5.4.276-syzkaller-04920-g3ffe89ed1bf9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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/0x460 arch/x86/kernel/apic/apic.c:1149 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:preempt_schedule_irq+0xc2/0x140 kernel/sched/core.c:4558 Code: 4c 89 e7 e8 40 d0 43 fd f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 4d bf 01 00 00 00 e8 14 91 f4 fc fb bf 01 00 00 00 b9 e6 ff ff fa bf 01 00 00 00 e8 7e 92 f4 fc 65 48 8b 1d d6 3f RSP: 0018:ffff8881e84af280 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffff1103d14590f RBX: 1ffff1103d095e54 RCX: ffffffff84512900 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffff8881e84af308 R08: dffffc0000000000 R09: ffffed103edeaf6d R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881e84af2a0 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff1103d095e50 retint_kernel+0x1b/0x1b RIP: 0010:dump_stack+0x207/0x241 lib/dump_stack.c:124 Code: e8 85 be 04 00 00 00 e8 d1 12 44 fd c7 05 27 52 98 01 ff ff ff ff 48 b8 00 00 00 00 00 fc ff df 4c 89 64 24 10 ff 74 24 10 9d <48> c7 44 24 20 0e 36 e0 45 48 8b 4c 24 08 48 c7 04 08 00 00 00 00 RSP: 0018:ffff8881e84af3c0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 00000000ffffffff RCX: ffffffff844fde4f RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff85e83080 RBP: ffff8881e84af470 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000246 R13: ffff8881e84af400 R14: 1ffff1103d095e80 R15: 0000000000000001 fail_dump lib/fault-inject.c:52 [inline] should_fail+0x71f/0x880 lib/fault-inject.c:144 should_failslab+0x5/0x20 mm/slab_common.c:1829 slab_pre_alloc_hook mm/slab.h:567 [inline] slab_alloc_node mm/slub.c:2742 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc+0x51/0x2e0 mm/slub.c:3909 kmalloc_array include/linux/slab.h:618 [inline] kcalloc include/linux/slab.h:629 [inline] pcpu_get_vm_areas+0x454/0x24f0 mm/vmalloc.c:3268 pcpu_create_chunk+0x71f/0xb80 mm/percpu-vm.c:340 pcpu_alloc+0x63e/0x1050 mm/percpu.c:1685 prealloc_init+0x238/0x800 kernel/bpf/hashtab.c:154 htab_map_alloc+0x638/0x930 kernel/bpf/hashtab.c:382 find_and_alloc_map kernel/bpf/syscall.c:122 [inline] map_create kernel/bpf/syscall.c:573 [inline] __do_sys_bpf kernel/bpf/syscall.c:2873 [inline] __se_sys_bpf+0x3291/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f4eb42a2ae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4eb3e250c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f4eb43c1f80 RCX: 00007f4eb42a2ae9 RDX: 0000000000000048 RSI: 0000000020000840 RDI: 0000000000000000 RBP: 00007f4eb3e25120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 000000000000000b R14: 00007f4eb43c1f80 R15: 00007ffd6ab97008 Allocated by task 0: (stack is not available) Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8881e8d4b000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 456 bytes inside of 512-byte region [ffff8881e8d4b000, ffff8881e8d4b200) The buggy address belongs to the page: page:ffffea0007a35200 refcount:1 mapcount:0 mapping:ffff8881f5c02500 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c02500 raw: 0000000000000000 0000000080100010 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_trace+0x12d/0x260 mm/slub.c:2854 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] inetdev_init+0x7e/0x450 net/ipv4/devinet.c:259 inetdev_event+0x205/0x1040 net/ipv4/devinet.c:1531 notifier_call_chain kernel/notifier.c:98 [inline] __raw_notifier_call_chain kernel/notifier.c:399 [inline] raw_notifier_call_chain+0x95/0x110 kernel/notifier.c:406 call_netdevice_notifiers_info net/core/dev.c:1670 [inline] call_netdevice_notifiers_extack net/core/dev.c:1682 [inline] call_netdevice_notifiers net/core/dev.c:1696 [inline] register_netdevice+0xeef/0x12a0 net/core/dev.c:9221 tun_set_iff+0x7f7/0xdc0 drivers/net/tun.c:2919 __tun_chr_ioctl+0x8a9/0x1d00 drivers/net/tun.c:3184 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 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 mm/page_alloc.c:4961 [inline] free_pages+0xf6/0x1b0 mm/page_alloc.c:4969 stack_depot_save+0x42b/0x480 lib/stackdepot.c:300 save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x1d9/0x210 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 radix_tree_node_alloc+0x190/0x3d0 lib/radix-tree.c:262 radix_tree_extend+0x112/0x510 lib/radix-tree.c:434 idr_get_free+0x192/0x980 lib/radix-tree.c:1501 idr_alloc_u32 lib/idr.c:46 [inline] idr_alloc_cyclic+0x1dc/0x5d0 lib/idr.c:125 inotify_add_to_idr fs/notify/inotify/inotify_user.c:365 [inline] inotify_new_watch fs/notify/inotify/inotify_user.c:578 [inline] inotify_update_watch fs/notify/inotify/inotify_user.c:617 [inline] __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:767 [inline] __se_sys_inotify_add_watch+0x697/0xa70 fs/notify/inotify/inotify_user.c:698 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Memory state around the buggy address: ffff8881e8d4b080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e8d4b100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881e8d4b180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881e8d4b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e8d4b280: 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 1eca14067 P4D 1eca14067 PUD 1ea582067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 573 Comm: syz-executor.1 Tainted: G B 5.4.276-syzkaller-04920-g3ffe89ed1bf9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010202 RAX: ffffffff8154d48a RBX: 0000000000000101 RCX: ffff8881e8a2bf00 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881e8d4b1c0 RBP: ffff8881f6f09ec8 R08: ffffffff8154d0ce R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffffa2a8 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e8d4b1c0 FS: 00007f4eb3e256c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001ea207000 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: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/0x460 arch/x86/kernel/apic/apic.c:1149 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:preempt_schedule_irq+0xc2/0x140 kernel/sched/core.c:4558 Code: 4c 89 e7 e8 40 d0 43 fd f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 4d bf 01 00 00 00 e8 14 91 f4 fc fb bf 01 00 00 00 b9 e6 ff ff fa bf 01 00 00 00 e8 7e 92 f4 fc 65 48 8b 1d d6 3f RSP: 0018:ffff8881e84af280 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffff1103d14590f RBX: 1ffff1103d095e54 RCX: ffffffff84512900 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffff8881e84af308 R08: dffffc0000000000 R09: ffffed103edeaf6d R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881e84af2a0 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff1103d095e50 retint_kernel+0x1b/0x1b RIP: 0010:dump_stack+0x207/0x241 lib/dump_stack.c:124 Code: e8 85 be 04 00 00 00 e8 d1 12 44 fd c7 05 27 52 98 01 ff ff ff ff 48 b8 00 00 00 00 00 fc ff df 4c 89 64 24 10 ff 74 24 10 9d <48> c7 44 24 20 0e 36 e0 45 48 8b 4c 24 08 48 c7 04 08 00 00 00 00 RSP: 0018:ffff8881e84af3c0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 00000000ffffffff RCX: ffffffff844fde4f RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff85e83080 RBP: ffff8881e84af470 R08: dffffc0000000000 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000246 R13: ffff8881e84af400 R14: 1ffff1103d095e80 R15: 0000000000000001 fail_dump lib/fault-inject.c:52 [inline] should_fail+0x71f/0x880 lib/fault-inject.c:144 should_failslab+0x5/0x20 mm/slab_common.c:1829 slab_pre_alloc_hook mm/slab.h:567 [inline] slab_alloc_node mm/slub.c:2742 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc+0x51/0x2e0 mm/slub.c:3909 kmalloc_array include/linux/slab.h:618 [inline] kcalloc include/linux/slab.h:629 [inline] pcpu_get_vm_areas+0x454/0x24f0 mm/vmalloc.c:3268 pcpu_create_chunk+0x71f/0xb80 mm/percpu-vm.c:340 pcpu_alloc+0x63e/0x1050 mm/percpu.c:1685 prealloc_init+0x238/0x800 kernel/bpf/hashtab.c:154 htab_map_alloc+0x638/0x930 kernel/bpf/hashtab.c:382 find_and_alloc_map kernel/bpf/syscall.c:122 [inline] map_create kernel/bpf/syscall.c:573 [inline] __do_sys_bpf kernel/bpf/syscall.c:2873 [inline] __se_sys_bpf+0x3291/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f4eb42a2ae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4eb3e250c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f4eb43c1f80 RCX: 00007f4eb42a2ae9 RDX: 0000000000000048 RSI: 0000000020000840 RDI: 0000000000000000 RBP: 00007f4eb3e25120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 000000000000000b R14: 00007f4eb43c1f80 R15: 00007ffd6ab97008 Modules linked in: CR2: 0000000000000000 ---[ end trace e33ebb29e5493c66 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010202 RAX: ffffffff8154d48a RBX: 0000000000000101 RCX: ffff8881e8a2bf00 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881e8d4b1c0 RBP: ffff8881f6f09ec8 R08: ffffffff8154d0ce R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffffa2a8 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e8d4b1c0 FS: 00007f4eb3e256c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001ea207000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 4c 89 e7 mov %r12,%rdi 3: e8 40 d0 43 fd call 0xfd43d048 8: f6 44 24 21 02 testb $0x2,0x21(%rsp) d: 74 0b je 0x1a f: 0f 0b ud2 11: 48 f7 03 08 00 00 00 testq $0x8,(%rbx) 18: 74 4d je 0x67 1a: bf 01 00 00 00 mov $0x1,%edi 1f: e8 14 91 f4 fc call 0xfcf49138 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 b9 e6 ff ff call 0xffffe6e8 <-- trapping instruction 2f: fa cli 30: bf 01 00 00 00 mov $0x1,%edi 35: e8 7e 92 f4 fc call 0xfcf492b8 3a: 65 gs 3b: 48 rex.W 3c: 8b .byte 0x8b 3d: 1d .byte 0x1d 3e: d6 (bad) 3f: 3f (bad)