================================================================== BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:787 [inline] BUG: KASAN: use-after-free in enqueue_timer kernel/time/timer.c:541 [inline] BUG: KASAN: use-after-free in __mod_timer+0xa90/0x1c70 kernel/time/timer.c:1062 Write of size 8 at addr ffff8881ea18b1c8 by task kworker/1:13/2203 CPU: 1 PID: 2203 Comm: kworker/1:13 Tainted: G W 5.4.125-syzkaller-00030-g1e429b8f9eb9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: wg-crypt-wg0 wg_packet_decrypt_worker Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x24e lib/dump_stack.c:118 print_address_description+0x9b/0x650 mm/kasan/report.c:384 __kasan_report+0x182/0x260 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 hlist_add_head include/linux/list.h:787 [inline] enqueue_timer kernel/time/timer.c:541 [inline] __mod_timer+0xa90/0x1c70 kernel/time/timer.c:1062 mod_peer_timer drivers/net/wireguard/timers.c:37 [inline] wg_timers_any_authenticated_packet_traversal+0x129/0x190 drivers/net/wireguard/timers.c:215 wg_packet_consume_data_done drivers/net/wireguard/receive.c:360 [inline] wg_packet_rx_poll+0xc6c/0x1eb0 drivers/net/wireguard/receive.c:480 napi_poll+0x195/0x670 net/core/dev.c:6335 net_rx_action+0x41c/0xb90 net/core/dev.c:6403 __do_softirq+0x23e/0x615 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1083 do_softirq+0x121/0x160 kernel/softirq.c:337 __local_bh_enable_ip+0x63/0x70 kernel/softirq.c:189 spin_unlock_bh include/linux/spinlock.h:383 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:366 [inline] wg_packet_decrypt_worker+0xc20/0xcc0 drivers/net/wireguard/receive.c:505 process_one_work+0x679/0x1030 kernel/workqueue.c:2277 worker_thread+0xa6f/0x1400 kernel/workqueue.c:2423 kthread+0x30f/0x330 kernel/kthread.c:268 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 150: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x137/0x1e0 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2821 [inline] slab_alloc mm/slub.c:2829 [inline] kmem_cache_alloc+0x115/0x290 mm/slub.c:2834 getname_flags+0xba/0x640 fs/namei.c:141 user_path_at_empty+0x28/0x50 fs/namei.c:2683 user_path_at include/linux/namei.h:49 [inline] vfs_statx fs/stat.c:187 [inline] vfs_lstat include/linux/fs.h:3361 [inline] __do_sys_newlstat fs/stat.c:354 [inline] __se_sys_newlstat+0xde/0x860 fs/stat.c:348 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 150: 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+0x18a/0x240 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1454 [inline] slab_free_freelist_hook+0x7b/0x150 mm/slub.c:1492 slab_free mm/slub.c:3072 [inline] kmem_cache_free+0xb8/0x5f0 mm/slub.c:3088 putname fs/namei.c:262 [inline] filename_lookup+0x4bb/0x6a0 fs/namei.c:2432 user_path_at include/linux/namei.h:49 [inline] vfs_statx fs/stat.c:187 [inline] vfs_lstat include/linux/fs.h:3361 [inline] __do_sys_newlstat fs/stat.c:354 [inline] __se_sys_newlstat+0xde/0x860 fs/stat.c:348 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881ea18a200 which belongs to the cache names_cache of size 4096 The buggy address is located 4040 bytes inside of 4096-byte region [ffff8881ea18a200, ffff8881ea18b200) The buggy address belongs to the page: page:ffffea0007a86200 refcount:1 mapcount:0 mapping:ffff8881f5cfa780 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5cfa780 raw: 0000000000000000 0000000000070007 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x19a/0x380 mm/page_alloc.c:2171 get_page_from_freelist+0x550/0x8b0 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x3a2/0x880 mm/page_alloc.c:4855 alloc_slab_page+0x39/0x3e0 mm/slub.c:342 allocate_slab mm/slub.c:1675 [inline] new_slab+0x97/0x460 mm/slub.c:1741 new_slab_objects mm/slub.c:2498 [inline] ___slab_alloc+0x330/0x4c0 mm/slub.c:2659 __slab_alloc mm/slub.c:2699 [inline] slab_alloc_node mm/slub.c:2784 [inline] slab_alloc mm/slub.c:2829 [inline] kmem_cache_alloc+0x18b/0x290 mm/slub.c:2834 getname_flags+0xba/0x640 fs/namei.c:141 user_path_at_empty+0x28/0x50 fs/namei.c:2683 user_path_at include/linux/namei.h:49 [inline] vfs_statx fs/stat.c:187 [inline] vfs_lstat include/linux/fs.h:3361 [inline] __do_sys_newlstat fs/stat.c:354 [inline] __se_sys_newlstat+0xde/0x860 fs/stat.c:348 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 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+0xc60/0xd80 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4917 [inline] __free_pages+0x8f/0x250 mm/page_alloc.c:4923 kfree+0x1ee/0x660 mm/slub.c:4058 device_release+0x70/0x1a0 drivers/base/core.c:1776 kobject_cleanup+0x1de/0x3c0 lib/kobject.c:708 tun_set_iff drivers/net/tun.c:2900 [inline] __tun_chr_ioctl+0x2b91/0x4d20 drivers/net/tun.c:3143 do_vfs_ioctl+0x76a/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+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Memory state around the buggy address: ffff8881ea18b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881ea18b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881ea18b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881ea18b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881ea18b280: 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 1e7349067 P4D 1e7349067 PUD 1b7e35067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 4713 Comm: syz-executor.4 Tainted: G B W 5.4.125-syzkaller-00030-g1e429b8f9eb9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09cd0 EFLAGS: 00010206 RAX: ffffffff81562548 RBX: 0000000000000100 RCX: ffff8881e8c32f40 RDX: 0000000080000100 RSI: 0000000000000000 RDI: ffff8881ea18b1c0 RBP: ffff8881ea18b1e0 R08: ffffffff8156230d R09: 0000000000000003 R10: ffffed103ede1391 R11: 0000000000000004 R12: 00000000ffffcbb0 R13: 1ffff1103ede7ef1 R14: 0000000000000000 R15: ffff8881ea18b1c0 FS: 00007fce001f1700(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001ddcb1000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: call_timer_fn+0x30/0x330 kernel/time/timer.c:1416 expire_timers+0x214/0x410 kernel/time/timer.c:1461 __run_timers+0x603/0x740 kernel/time/timer.c:1785 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1798 __do_softirq+0x23e/0x615 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+0x113/0x420 arch/x86/kernel/apic/apic.c:1150 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:831 RIP: 0010:rw_copy_check_uvector+0x0/0x2f0 fs/read_write.c:768 Code: f1 80 e1 07 80 c1 03 38 c1 0f 8c 3c ff ff ff 4c 89 f7 e8 d3 62 fc ff e9 2f ff ff ff e8 29 1a a5 ff 66 0f 1f 84 00 00 00 00 00 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 28 4d 89 cf 4c 89 04 24 48 RSP: 0018:ffff8881ef727978 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff8881ef7279e0 RCX: 0000000000000008 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8881ef727a50 R08: ffff8881ef727c60 R09: ffff8881ef7279e0 R10: ffffed103dee4f5b R11: 0000000000000000 R12: 1ffff1103dee4f84 R13: ffff8881ef7279e0 R14: ffff8881ef727d50 R15: 0000000000000008 import_iovec+0x10d/0x380 lib/iov_iter.c:1649 copy_msghdr_from_user+0x443/0x720 net/socket.c:2230 recvmsg_copy_msghdr net/socket.c:2500 [inline] ___sys_recvmsg net/socket.c:2567 [inline] do_recvmmsg+0x430/0xb40 net/socket.c:2682 __sys_recvmmsg net/socket.c:2761 [inline] __do_sys_recvmmsg net/socket.c:2784 [inline] __se_sys_recvmmsg net/socket.c:2777 [inline] __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2777 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fce0249a8d9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fce001f1188 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fce0259f020 RCX: 00007fce0249a8d9 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007fce024f4cb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd51a0cdcf R14: 00007fce001f1300 R15: 0000000000022000 Modules linked in: CR2: 0000000000000000 ---[ end trace cacd0e152d6eeadd ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09cd0 EFLAGS: 00010206 RAX: ffffffff81562548 RBX: 0000000000000100 RCX: ffff8881e8c32f40 RDX: 0000000080000100 RSI: 0000000000000000 RDI: ffff8881ea18b1c0 RBP: ffff8881ea18b1e0 R08: ffffffff8156230d R09: 0000000000000003 R10: ffffed103ede1391 R11: 0000000000000004 R12: 00000000ffffcbb0 R13: 1ffff1103ede7ef1 R14: 0000000000000000 R15: ffff8881ea18b1c0 FS: 00007fce001f1700(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001ddcb1000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: f1 icebp 1: 80 e1 07 and $0x7,%cl 4: 80 c1 03 add $0x3,%cl 7: 38 c1 cmp %al,%cl 9: 0f 8c 3c ff ff ff jl 0xffffff4b f: 4c 89 f7 mov %r14,%rdi 12: e8 d3 62 fc ff callq 0xfffc62ea 17: e9 2f ff ff ff jmpq 0xffffff4b 1c: e8 29 1a a5 ff callq 0xffa51a4a 21: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 28: 00 00 * 2a: 55 push %rbp <-- trapping instruction 2b: 41 57 push %r15 2d: 41 56 push %r14 2f: 41 55 push %r13 31: 41 54 push %r12 33: 53 push %rbx 34: 48 83 ec 28 sub $0x28,%rsp 38: 4d 89 cf mov %r9,%r15 3b: 4c 89 04 24 mov %r8,(%rsp) 3f: 48 rex.W