==================================================================
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+0x759/0xb60 kernel/time/timer.c:1817
Write of size 8 at addr ffff8881cf9c71c8 by task syz.5.235/1249
CPU: 0 PID: 1249 Comm: syz.5.235 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_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+0x759/0xb60 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:__fib6_clean_all net/ipv6/ip6_fib.c:2150 [inline]
RIP: 0010:fib6_clean_all+0x1b5/0x230 net/ipv6/ip6_fib.c:2165
Code: ff df 80 3c 08 00 74 08 4c 89 ef e8 a5 d0 d8 fd 4d 8b 6d 00 4d 85 ed 0f 85 6a ff ff ff e8 63 d6 aa fd 4c 8b 74 24 28 49 ff c6 <49> 81 fe 00 01 00 00 48 8b 5c 24 20 74 0a e8 48 d6 aa fd e9 dc fe
RSP: 0018:ffff8881e3b675e0 EFLAGS: 00000203 ORIG_RAX: ffffffffffffff13
RAX: ffffffff83b4a7dd RBX: ffff8881d69f0720 RCX: 0000000000080000
RDX: ffffc90007d5c000 RSI: 000000000000183e RDI: 000000000000183f
RBP: ffff8881e3b67730 R08: dffffc0000000000 R09: ffff8881e3b67769
R10: ffffed103c76ceee R11: 1ffff1103c76ceed R12: ffff8881e3b67640
R13: 0000000000000000 R14: 00000000000000a8 R15: ffff8881d69f0000
rt6_sync_up+0x11d/0x150 net/ipv6/route.c:4670
addrconf_notify+0x864/0xeb0 net/ipv6/addrconf.c:3632
notifier_call_chain kernel/notifier.c:98 [inline]
__raw_notifier_call_chain kernel/notifier.c:399 [inline]
raw_notifier_call_chain+0xa0/0x120 kernel/notifier.c:406
call_netdevice_notifiers_info net/core/dev.c:1670 [inline]
netdev_state_change+0x102/0x1a0 net/core/dev.c:1273
old_dev_ioctl net/bridge/br_ioctl.c:294 [inline]
br_dev_ioctl+0x10ed/0x13b0 net/bridge/br_ioctl.c:388
dev_ifsioc+0x6a1/0xa40 net/core/dev_ioctl.c:311
dev_ioctl+0x5ea/0xb80 net/core/dev_ioctl.c:508
sock_ioctl+0x6a1/0x710 net/socket.c:1112
do_vfs_ioctl+0x753/0x13f0 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+0xe1/0x120 fs/ioctl.c:747
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f05ba9dd969
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:00007f05b9046038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f05bac04fa0 RCX: 00007f05ba9dd969
RDX: 0000200000000080 RSI: 00000000000089f0 RDI: 0000000000000006
RBP: 00007f05baa5fab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f05bac04fa0 R15: 00007ffe10451948
The buggy address belongs to the page:
page:ffffea00073e71c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea00073e7188 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 2, migratetype Unmovable, gfp_mask 0x146dc0(GFP_USER|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP|__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]
kmalloc_order mm/slab_common.c:1342 [inline]
kmalloc_order_trace+0x31/0x100 mm/slab_common.c:1358
kmalloc_large include/linux/slab.h:485 [inline]
__kmalloc+0x162/0x2f0 mm/slub.c:3902
__kmalloc_node include/linux/slab.h:422 [inline]
kmalloc_node include/linux/slab.h:599 [inline]
kvmalloc_node+0x88/0xf0 mm/util.c:596
kvmalloc include/linux/mm.h:761 [inline]
kvzalloc include/linux/mm.h:769 [inline]
alloc_netdev_mqs+0x88/0xc50 net/core/dev.c:9629
tun_set_iff+0x535/0xe00 drivers/net/tun.c:2893
__tun_chr_ioctl+0x771/0x18a0 drivers/net/tun.c:3187
tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3470
do_vfs_ioctl+0x753/0x13f0 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+0xe1/0x120 fs/ioctl.c:747
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_pages_ok+0x7e4/0x910 mm/page_alloc.c:1438
free_the_page mm/page_alloc.c:4956 [inline]
__free_pages+0x8c/0x110 mm/page_alloc.c:4962
kfree+0x1ca/0x260 mm/slub.c:4068
kvfree+0x4c/0x50 mm/util.c:625
netdev_freemem net/core/dev.c:9583 [inline]
alloc_netdev_mqs+0x18d/0xc50 net/core/dev.c:9701
tun_set_iff+0x535/0xe00 drivers/net/tun.c:2893
__tun_chr_ioctl+0x771/0x18a0 drivers/net/tun.c:3187
tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3470
do_vfs_ioctl+0x753/0x13f0 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+0xe1/0x120 fs/ioctl.c:747
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Memory state around the buggy address:
ffff8881cf9c7080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881cf9c7100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881cf9c7180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881cf9c7200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881cf9c7280: 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 1eacb3067 P4D 1eacb3067 PUD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 1249 Comm: syz.5.235 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:ffff8881f6e09cf0 EFLAGS: 00010206
RAX: ffffffff8150a590 RBX: 0000000000000100 RCX: ffff8881e4292f40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881cf9c71c0
RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffffaff8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881cf9c71c0
FS: 00007f05b90466c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001d39cf000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 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:__fib6_clean_all net/ipv6/ip6_fib.c:2150 [inline]
RIP: 0010:fib6_clean_all+0x1b5/0x230 net/ipv6/ip6_fib.c:2165
Code: ff df 80 3c 08 00 74 08 4c 89 ef e8 a5 d0 d8 fd 4d 8b 6d 00 4d 85 ed 0f 85 6a ff ff ff e8 63 d6 aa fd 4c 8b 74 24 28 49 ff c6 <49> 81 fe 00 01 00 00 48 8b 5c 24 20 74 0a e8 48 d6 aa fd e9 dc fe
RSP: 0018:ffff8881e3b675e0 EFLAGS: 00000203 ORIG_RAX: ffffffffffffff13
RAX: ffffffff83b4a7dd RBX: ffff8881d69f0720 RCX: 0000000000080000
RDX: ffffc90007d5c000 RSI: 000000000000183e RDI: 000000000000183f
RBP: ffff8881e3b67730 R08: dffffc0000000000 R09: ffff8881e3b67769
R10: ffffed103c76ceee R11: 1ffff1103c76ceed R12: ffff8881e3b67640
R13: 0000000000000000 R14: 00000000000000a8 R15: ffff8881d69f0000
rt6_sync_up+0x11d/0x150 net/ipv6/route.c:4670
addrconf_notify+0x864/0xeb0 net/ipv6/addrconf.c:3632
notifier_call_chain kernel/notifier.c:98 [inline]
__raw_notifier_call_chain kernel/notifier.c:399 [inline]
raw_notifier_call_chain+0xa0/0x120 kernel/notifier.c:406
call_netdevice_notifiers_info net/core/dev.c:1670 [inline]
netdev_state_change+0x102/0x1a0 net/core/dev.c:1273
old_dev_ioctl net/bridge/br_ioctl.c:294 [inline]
br_dev_ioctl+0x10ed/0x13b0 net/bridge/br_ioctl.c:388
dev_ifsioc+0x6a1/0xa40 net/core/dev_ioctl.c:311
dev_ioctl+0x5ea/0xb80 net/core/dev_ioctl.c:508
sock_ioctl+0x6a1/0x710 net/socket.c:1112
do_vfs_ioctl+0x753/0x13f0 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+0xe1/0x120 fs/ioctl.c:747
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f05ba9dd969
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:00007f05b9046038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f05bac04fa0 RCX: 00007f05ba9dd969
RDX: 0000200000000080 RSI: 00000000000089f0 RDI: 0000000000000006
RBP: 00007f05baa5fab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f05bac04fa0 R15: 00007ffe10451948
Modules linked in:
CR2: 0000000000000000
---[ end trace 67725c4deed59fc0 ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09cf0 EFLAGS: 00010206
RAX: ffffffff8150a590 RBX: 0000000000000100 RCX: ffff8881e4292f40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881cf9c71c0
RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffffaff8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881cf9c71c0
FS: 00007f05b90466c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001d39cf000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess), 1 bytes skipped:
0: df 80 3c 08 00 74 filds 0x7400083c(%rax)
6: 08 4c 89 ef or %cl,-0x11(%rcx,%rcx,4)
a: e8 a5 d0 d8 fd call 0xfdd8d0b4
f: 4d 8b 6d 00 mov 0x0(%r13),%r13
13: 4d 85 ed test %r13,%r13
16: 0f 85 6a ff ff ff jne 0xffffff86
1c: e8 63 d6 aa fd call 0xfdaad684
21: 4c 8b 74 24 28 mov 0x28(%rsp),%r14
26: 49 ff c6 inc %r14
* 29: 49 81 fe 00 01 00 00 cmp $0x100,%r14 <-- trapping instruction
30: 48 8b 5c 24 20 mov 0x20(%rsp),%rbx
35: 74 0a je 0x41
37: e8 48 d6 aa fd call 0xfdaad684
3c: e9 .byte 0xe9
3d: dc fe fdivr %st,%st(6)