================================================================== BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:791 [inline] BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:824 [inline] BUG: KASAN: use-after-free in expire_timers kernel/time/timer.c:1482 [inline] BUG: KASAN: use-after-free in __run_timers+0x7be/0xbe0 kernel/time/timer.c:1817 Write of size 8 at addr ffff8881e5f6f1c8 by task syz-executor.1/8284 CPU: 0 PID: 8284 Comm: syz-executor.1 Tainted: G W 5.4.274-syzkaller-00002-g6f97bd951d82 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 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_del include/linux/list.h:791 [inline] detach_timer kernel/time/timer.c:824 [inline] expire_timers kernel/time/timer.c:1482 [inline] __run_timers+0x7be/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:538 [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:deref_stack_reg+0x151/0x1f0 arch/x86/kernel/unwind_orc.c:350 Code: 40 4c 89 f3 48 c1 eb 03 49 bc 00 00 00 00 00 fc ff df 42 80 3c 23 00 74 08 4c 89 f7 e8 58 41 64 00 48 c7 44 24 40 00 00 00 00 <4c> 89 ff 4c 89 f6 e8 24 09 00 00 42 80 3c 23 00 74 08 4c 89 f7 e8 RSP: 0018:ffff8881e8aaed40 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffff8881e8aaf8f8 RBX: 1ffff1103d155db0 RCX: dffffc0000000000 RDX: ffff8881e8aaf140 RSI: ffff8881e8aaf8f0 RDI: ffff8881e8aaf110 RBP: ffff8881e8aaedf0 R08: dffffc0000000000 R09: ffff8881e8aaf150 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff1103d155dac R14: ffff8881e8aaed80 R15: ffff8881e8aaf8f0 unwind_next_frame+0x1681/0x1ea0 arch/x86/kernel/unwind_orc.c:579 arch_stack_walk+0x111/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1c0 kernel/stacktrace.c:123 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 kmem_cache_zalloc include/linux/slab.h:680 [inline] __kernfs_new_node+0xdb/0x6e0 fs/kernfs/dir.c:639 kernfs_new_node+0x130/0x230 fs/kernfs/dir.c:717 __kernfs_create_file+0x45/0x260 fs/kernfs/file.c:1001 sysfs_add_file_mode_ns+0x292/0x340 fs/sysfs/file.c:306 create_files fs/sysfs/group.c:63 [inline] internal_create_group+0x573/0xf00 fs/sysfs/group.c:148 internal_create_groups fs/sysfs/group.c:188 [inline] sysfs_create_groups+0x52/0x110 fs/sysfs/group.c:214 device_add_groups drivers/base/core.c:2004 [inline] device_add_attrs+0x87/0x370 drivers/base/core.c:2152 device_add+0x4f4/0xbb0 drivers/base/core.c:2859 netdev_register_kobject+0x176/0x310 net/core/net-sysfs.c:1854 register_netdevice+0xbc5/0x12a0 net/core/dev.c:9190 tun_set_iff+0x7f7/0xdc0 drivers/net/tun.c:2917 __tun_chr_ioctl+0x8a9/0x1d00 drivers/net/tun.c:3182 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 RIP: 0033:0x7f89b4754ea9 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:00007f89b3acf0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f89b488bf80 RCX: 00007f89b4754ea9 RDX: 0000000020000080 RSI: 00000000400454ca RDI: 0000000000000008 RBP: 00007f89b47c3ff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f89b488bf80 R15: 00007fff7a4d7a18 Allocated by task 8259: 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] __kmalloc_track_caller+0x100/0x2b0 mm/slub.c:4449 __kmalloc_reserve net/core/skbuff.c:142 [inline] pskb_expand_head+0x10c/0x10b0 net/core/skbuff.c:1647 __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+0x110/0x350 net/core/filter.c:2123 0xffffffffa00a860f bpf_call_func include/linux/filter.h:627 [inline] bpf_test_run+0x2ae/0x6c0 net/bpf/test_run.c:44 bpf_prog_test_run_skb+0x73c/0xf00 net/bpf/test_run.c:311 bpf_prog_test_run kernel/bpf/syscall.c:2124 [inline] __do_sys_bpf kernel/bpf/syscall.c:2909 [inline] __se_sys_bpf+0x2e37/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 8291: 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] kfree+0x123/0x370 mm/slub.c:4071 skb_release_all net/core/skbuff.c:675 [inline] __kfree_skb net/core/skbuff.c:689 [inline] consume_skb+0xa5/0x2a0 net/core/skbuff.c:849 tun_do_read+0x1265/0x1ec0 drivers/net/tun.c:2335 tun_chr_read_iter+0x1d0/0x2d0 drivers/net/tun.c:2355 call_read_iter include/linux/fs.h:1983 [inline] new_sync_read fs/read_write.c:414 [inline] __vfs_read+0x5cd/0x730 fs/read_write.c:427 vfs_read+0x148/0x360 fs/read_write.c:461 ksys_read+0x199/0x2c0 fs/read_write.c:587 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 The buggy address belongs to the object at ffff8881e5f6f000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 456 bytes inside of 512-byte region [ffff8881e5f6f000, ffff8881e5f6f200) The buggy address belongs to the page: page:ffffea000797db00 refcount:1 mapcount:0 mapping:ffff8881f5c02500 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c02500 raw: 0000000000000000 0000000000100010 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 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+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_track_caller+0x16d/0x2b0 mm/slub.c:4449 __kmalloc_reserve net/core/skbuff.c:142 [inline] pskb_expand_head+0x10c/0x10b0 net/core/skbuff.c:1647 __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+0x110/0x350 net/core/filter.c:2123 0xffffffffa005877e bpf_call_func include/linux/filter.h:627 [inline] bpf_test_run+0x2ae/0x6c0 net/bpf/test_run.c:44 bpf_prog_test_run_skb+0x73c/0xf00 net/bpf/test_run.c:311 bpf_prog_test_run kernel/bpf/syscall.c:2124 [inline] __do_sys_bpf kernel/bpf/syscall.c:2909 [inline] __se_sys_bpf+0x2e37/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 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_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+0x8aaa/0xb340 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: ffff8881e5f6f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881e5f6f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881e5f6f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881e5f6f200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e5f6f280: 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 1e7083067 P4D 1e7083067 PUD 1dd4c1067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 8284 Comm: syz-executor.1 Tainted: G B W 5.4.274-syzkaller-00002-g6f97bd951d82 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202 RAX: ffffffff8154d7aa RBX: 0000000000000101 RCX: ffff8881e1a81f80 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881e5f6f1c0 RBP: ffff8881f6e09ec8 R08: ffffffff8154d3ee R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000100001a38 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e5f6f1c0 FS: 00007f89b3acf6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001e000d000 CR4: 00000000003406b0 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:538 [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:deref_stack_reg+0x151/0x1f0 arch/x86/kernel/unwind_orc.c:350 Code: 40 4c 89 f3 48 c1 eb 03 49 bc 00 00 00 00 00 fc ff df 42 80 3c 23 00 74 08 4c 89 f7 e8 58 41 64 00 48 c7 44 24 40 00 00 00 00 <4c> 89 ff 4c 89 f6 e8 24 09 00 00 42 80 3c 23 00 74 08 4c 89 f7 e8 RSP: 0018:ffff8881e8aaed40 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffff8881e8aaf8f8 RBX: 1ffff1103d155db0 RCX: dffffc0000000000 RDX: ffff8881e8aaf140 RSI: ffff8881e8aaf8f0 RDI: ffff8881e8aaf110 RBP: ffff8881e8aaedf0 R08: dffffc0000000000 R09: ffff8881e8aaf150 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff1103d155dac R14: ffff8881e8aaed80 R15: ffff8881e8aaf8f0 unwind_next_frame+0x1681/0x1ea0 arch/x86/kernel/unwind_orc.c:579 arch_stack_walk+0x111/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1c0 kernel/stacktrace.c:123 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 kmem_cache_zalloc include/linux/slab.h:680 [inline] __kernfs_new_node+0xdb/0x6e0 fs/kernfs/dir.c:639 kernfs_new_node+0x130/0x230 fs/kernfs/dir.c:717 __kernfs_create_file+0x45/0x260 fs/kernfs/file.c:1001 sysfs_add_file_mode_ns+0x292/0x340 fs/sysfs/file.c:306 create_files fs/sysfs/group.c:63 [inline] internal_create_group+0x573/0xf00 fs/sysfs/group.c:148 internal_create_groups fs/sysfs/group.c:188 [inline] sysfs_create_groups+0x52/0x110 fs/sysfs/group.c:214 device_add_groups drivers/base/core.c:2004 [inline] device_add_attrs+0x87/0x370 drivers/base/core.c:2152 device_add+0x4f4/0xbb0 drivers/base/core.c:2859 netdev_register_kobject+0x176/0x310 net/core/net-sysfs.c:1854 register_netdevice+0xbc5/0x12a0 net/core/dev.c:9190 tun_set_iff+0x7f7/0xdc0 drivers/net/tun.c:2917 __tun_chr_ioctl+0x8a9/0x1d00 drivers/net/tun.c:3182 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 RIP: 0033:0x7f89b4754ea9 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:00007f89b3acf0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f89b488bf80 RCX: 00007f89b4754ea9 RDX: 0000000020000080 RSI: 00000000400454ca RDI: 0000000000000008 RBP: 00007f89b47c3ff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f89b488bf80 R15: 00007fff7a4d7a18 Modules linked in: CR2: 0000000000000000 ---[ end trace 170492fc376a1be8 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202 RAX: ffffffff8154d7aa RBX: 0000000000000101 RCX: ffff8881e1a81f80 RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881e5f6f1c0 RBP: ffff8881f6e09ec8 R08: ffffffff8154d3ee R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000100001a38 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881e5f6f1c0 FS: 00007f89b3acf6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001e000d000 CR4: 00000000003406b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 40 rex 1: 4c 89 f3 mov %r14,%rbx 4: 48 c1 eb 03 shr $0x3,%rbx 8: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12 f: fc ff df 12: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1) 17: 74 08 je 0x21 19: 4c 89 f7 mov %r14,%rdi 1c: e8 58 41 64 00 call 0x644179 21: 48 c7 44 24 40 00 00 movq $0x0,0x40(%rsp) 28: 00 00 * 2a: 4c 89 ff mov %r15,%rdi <-- trapping instruction 2d: 4c 89 f6 mov %r14,%rsi 30: e8 24 09 00 00 call 0x959 35: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1) 3a: 74 08 je 0x44 3c: 4c 89 f7 mov %r14,%rdi 3f: e8 .byte 0xe8