==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
Write of size 8 at addr ffff8881dc4931c8 by task syz.2.888/3480
CPU: 0 PID: 3480 Comm: syz.2.888 Not tainted 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_add_head include/linux/list.h:814 [inline]
enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
__internal_add_timer kernel/time/timer.c:554 [inline]
internal_add_timer+0x208/0x3e0 kernel/time/timer.c:604
__mod_timer+0x5ab/0x1150 kernel/time/timer.c:1065
mod_timer+0x1f/0x30 kernel/time/timer.c:1117
can_stat_update+0xbab/0xc40 net/can/proc.c:186
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
do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1086
do_softirq+0xf9/0x140 kernel/softirq.c:337
__local_bh_enable_ip+0x70/0x80 kernel/softirq.c:189
local_bh_enable+0x1f/0x30 include/linux/bottom_half.h:32
get_next_corpse net/netfilter/nf_conntrack_core.c:2069 [inline]
nf_ct_iterate_cleanup+0x27c/0x310 net/netfilter/nf_conntrack_core.c:2092
nf_conntrack_cleanup_net_list+0x62/0x200 net/netfilter/nf_conntrack_core.c:2279
nf_conntrack_pernet_exit+0x146/0x160 net/netfilter/nf_conntrack_standalone.c:1153
ops_exit_list net/core/net_namespace.c:187 [inline]
setup_net+0x638/0x9b0 net/core/net_namespace.c:371
copy_net_ns+0x314/0x520 net/core/net_namespace.c:489
create_new_namespaces+0x49c/0x590 kernel/nsproxy.c:103
copy_namespaces+0x17e/0x1c0 kernel/nsproxy.c:161
copy_process+0x1194/0x2cf0 kernel/fork.c:2055
_do_fork+0x190/0x860 kernel/fork.c:2399
__do_sys_clone kernel/fork.c:2557 [inline]
__se_sys_clone kernel/fork.c:2538 [inline]
__x64_sys_clone+0x12e/0x160 kernel/fork.c:2538
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f036a510969
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:00007f0368b57fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f036a738080 RCX: 00007f036a510969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000640c7000
RBP: 00007f036a592ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f036a738080 R15: 00007ffd4e7a3b68
The buggy address belongs to the page:
page:ffffea00077124c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffffff07710101 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 0x152dc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__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]
bpf_check+0xfb/0x9cf0 kernel/bpf/verifier.c:9561
bpf_prog_load+0xa5f/0xe10 kernel/bpf/syscall.c:1724
__do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
__se_sys_bpf+0x435/0x570 kernel/bpf/syscall.c:2849
__x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
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
bpf_check+0x8371/0x9cf0 kernel/bpf/verifier.c:9731
bpf_prog_load+0xa5f/0xe10 kernel/bpf/syscall.c:1724
__do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
__se_sys_bpf+0x435/0x570 kernel/bpf/syscall.c:2849
__x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Memory state around the buggy address:
ffff8881dc493080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881dc493100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881dc493180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881dc493200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881dc493280: 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 0 P4D 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3654 Comm: syz-executor Tainted: G B 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: 00010202
RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881d7759f80
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881dc4931c0
RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffffb318
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881dc4931c0
FS: 0000555556532500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001dd639000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000200000000300 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:native_restore_fl arch/x86/include/asm/irqflags.h:41 [inline]
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:84 [inline]
RIP: 0010:console_unlock+0x9ea/0xe80 kernel/printk/printk.c:2527
Code: 64 56 86 e8 48 73 e1 02 f6 c3 01 48 8b 5c 24 28 0f 85 61 04 00 00 e8 55 f9 15 00 e8 80 5a 00 00 48 89 5c 24 70 ff 74 24 70 9d d0 f7 ff ff e8 3c f9 15 00 48 c7 05 d1 d7 0c 05 00 00 00 00 e9
RSP: 0018:ffff8881dd736760 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff8149e019 RBX: 0000000000000293 RCX: ffff8881d7759f80
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00000000ffffffff
RBP: ffff8881dd736910 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103bae6cdc R11: 1ffff1103bae6cdc R12: 0000000000000000
R13: ffffffff85eefb30 R14: ffffffff8267bbc0 R15: dffffc0000000000
vprintk_emit+0x1be/0x380 kernel/printk/printk.c:2032
vprintk_default+0x28/0x30 kernel/printk/printk.c:2059
vprintk_func+0x19a/0x1e0 kernel/printk/printk_safe.c:393
printk+0xcc/0x110 kernel/printk/printk.c:2092
br_set_state+0x123/0x190 net/bridge/br_stp.c:45
br_init_port+0x9c/0x210 net/bridge/br_stp_if.c:39
new_nbp+0x4af/0x640 net/bridge/br_if.c:430
br_add_if+0x291/0x10a0 net/bridge/br_if.c:595
br_add_slave+0x2c/0x40 net/bridge/br_device.c:375
do_set_master net/core/rtnetlink.c:2413 [inline]
do_setlink+0xd3e/0x39e0 net/core/rtnetlink.c:2549
__rtnl_newlink net/core/rtnetlink.c:3188 [inline]
rtnl_newlink+0x1136/0x15f0 net/core/rtnetlink.c:3314
rtnetlink_rcv_msg+0xa23/0xbe0 net/core/rtnetlink.c:5290
netlink_rcv_skb+0x1e6/0x430 net/netlink/af_netlink.c:2467
rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5308
netlink_unicast_kernel net/netlink/af_netlink.c:1306 [inline]
netlink_unicast+0x88b/0xa40 net/netlink/af_netlink.c:1332
netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1900
sock_sendmsg_nosec net/socket.c:638 [inline]
__sock_sendmsg net/socket.c:650 [inline]
__sys_sendto+0x414/0x570 net/socket.c:1961
__do_sys_sendto net/socket.c:1973 [inline]
__se_sys_sendto net/socket.c:1969 [inline]
__x64_sys_sendto+0xe5/0x100 net/socket.c:1969
do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f105557f7a3
Code: 64 89 02 48 c7 c0 ff ff ff ff eb b7 66 2e 0f 1f 84 00 00 00 00 00 90 80 3d a1 3d 1f 00 00 41 89 ca 74 14 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 75 c3 0f 1f 40 00 55 48 83 ec 30 44 89 4c 24
RSP: 002b:00007fff4ea960e8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f10562d3620 RCX: 00007f105557f7a3
RDX: 0000000000000028 RSI: 00007f10562d3670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff4ea96104 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f10562d3670 R15: 0000000000000000
Modules linked in:
CR2: 0000000000000000
---[ end trace 8fd3faea5ebd604a ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09cf0 EFLAGS: 00010202
RAX: ffffffff8150a590 RBX: 0000000000000101 RCX: ffff8881d7759f80
RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881dc4931c0
RBP: ffff8881f6e09d30 R08: 0000000000000004 R09: 0000000000000003
R10: ffffed103edc1398 R11: 1ffff1103edc1398 R12: 00000000ffffb318
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881dc4931c0
FS: 0000555556532500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001dd639000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
0: 64 56 fs push %rsi
2: 86 e8 xchg %ch,%al
4: 48 73 e1 rex.W jae 0xffffffe8
7: 02 f6 add %dh,%dh
9: c3 ret
a: 01 48 8b add %ecx,-0x75(%rax)
d: 5c pop %rsp
e: 24 28 and $0x28,%al
10: 0f 85 61 04 00 00 jne 0x477
16: e8 55 f9 15 00 call 0x15f970
1b: e8 80 5a 00 00 call 0x5aa0
20: 48 89 5c 24 70 mov %rbx,0x70(%rsp)
25: ff 74 24 70 push 0x70(%rsp)
29: 9d popf
* 2a: e9 d0 f7 ff ff jmp 0xfffff7ff <-- trapping instruction
2f: e8 3c f9 15 00 call 0x15f970
34: 48 c7 05 d1 d7 0c 05 movq $0x0,0x50cd7d1(%rip) # 0x50cd810
3b: 00 00 00 00
3f: e9 .byte 0xe9