==================================================================
BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274
Write of size 32 at addr ffff88804fb86e10 by task syz.4.11757/13391
CPU: 0 PID: 13391 Comm: syz.4.11757 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:420
kasan_report+0x10b/0x140 mm/kasan/report.c:524
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x235/0x290 mm/kasan/generic.c:189
memcpy+0x3c/0x60 mm/kasan/shadow.c:66
__bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274
____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline]
bpf_get_stackid_pe+0x33f/0x400 kernel/bpf/stackmap.c:334
bpf_prog_43b50326510579ba+0x21/0x36
bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline]
__bpf_prog_run include/linux/filter.h:607 [inline]
bpf_prog_run include/linux/filter.h:614 [inline]
bpf_overflow_handler+0x522/0x7c0 kernel/events/core.c:10321
__perf_event_overflow+0x448/0x610 kernel/events/core.c:9496
perf_event_overflow kernel/events/core.c:9517 [inline]
perf_swevent_hrtimer+0x472/0x630 kernel/events/core.c:10967
__run_hrtimer kernel/time/hrtimer.c:1747 [inline]
__hrtimer_run_queues+0x50b/0xd50 kernel/time/hrtimer.c:1811
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:319 [inline]
RIP: 0010:handle_softirqs+0x1c8/0x930 kernel/softirq.c:584
Code: 89 7c 24 44 0f b7 db 48 c7 c7 00 07 8b 8a e8 bf 90 de 08 65 66 c7 05 a5 35 b4 7e 00 00 e8 80 73 39 00 fb 49 c7 c6 c0 a0 80 8c <89> 5c 24 4c b8 ff ff ff ff 0f bc 44 24 4c 41 89 c5 41 ff c5 0f 84
RSP: 0000:ffffc9000403fd60 EFLAGS: 00000286
RAX: da0031a96c3edf00 RBX: 0000000000000082 RCX: da0031a96c3edf00
RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: ffffffff8adf1320
RBP: ffffc9000403fe90 R08: ffffffff8fa0e008 R09: ffffffff8fa0e018
R10: ffffffff8fa0e010 R11: ffffffff8fa0e003 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff8c80a0c0 R15: 000000000000000a
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0033:0x7fe451f9cdc3
Code: 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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
RSP: 002b:00007fe452f290e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fe452215fa8 RCX: 00000000000f4240
RDX: 0000000000000081 RSI: 00007fe452215fac RDI: 00000000000000ca
RBP: 00007fe452215fa0 R08: 0000000000000000 R09: 0019dba3d6c9207e
R10: 0000054c65fdfc6b R11: 000000000007d3e4 R12: 0000000000000000
R13: 00007fe452216038 R14: 00007ffc3a221450 R15: 00007ffc3a221538
Allocated by task 13391:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slab_common.c:936 [inline]
__kmalloc_node+0xb0/0x240 mm/slab_common.c:943
kmalloc_node include/linux/slab.h:589 [inline]
__bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline]
bpf_map_area_alloc+0x47/0xe0 kernel/bpf/syscall.c:341
prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51
stack_map_alloc+0x390/0x520 kernel/bpf/stackmap.c:117
find_and_alloc_map kernel/bpf/syscall.c:133 [inline]
map_create+0x534/0x1000 kernel/bpf/syscall.c:1149
__sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5013
__do_sys_bpf kernel/bpf/syscall.c:5135 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5133 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5133
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849
nf_unregister_net_hook net/netfilter/core.c:-1 [inline]
nf_unregister_net_hooks+0xc7/0x130 net/netfilter/core.c:601
nf_defrag_ipv4_disable+0x91/0xe0 net/ipv4/netfilter/nf_defrag_ipv4.c:162
nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:562 [inline]
nf_ct_netns_put+0x2d6/0x510 net/netfilter/nf_conntrack_proto.c:641
nf_conncount_destroy+0x3d/0x150 net/netfilter/nf_conncount.c:688
ovs_ct_limit_exit net/openvswitch/conntrack.c:1919 [inline]
ovs_ct_exit+0x98/0x200 net/openvswitch/conntrack.c:2322
ovs_exit_net+0xe9/0x7a0 net/openvswitch/datapath.c:2655
ops_exit_list net/core/net_namespace.c:172 [inline]
cleanup_net+0x706/0xba0 net/core/net_namespace.c:640
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Second to last potentially related work creation:
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849
nf_unregister_net_hook net/netfilter/core.c:-1 [inline]
nf_unregister_net_hooks+0xc7/0x130 net/netfilter/core.c:601
nf_defrag_ipv4_disable+0x91/0xe0 net/ipv4/netfilter/nf_defrag_ipv4.c:162
nf_ct_netns_do_put net/netfilter/nf_conntrack_proto.c:562 [inline]
nf_ct_netns_put+0x2d6/0x510 net/netfilter/nf_conntrack_proto.c:641
nf_conncount_destroy+0x3d/0x150 net/netfilter/nf_conncount.c:688
ovs_ct_limit_exit net/openvswitch/conntrack.c:1919 [inline]
ovs_ct_exit+0x98/0x200 net/openvswitch/conntrack.c:2322
ovs_exit_net+0xe9/0x7a0 net/openvswitch/datapath.c:2655
ops_exit_list net/core/net_namespace.c:172 [inline]
cleanup_net+0x706/0xba0 net/core/net_namespace.c:640
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
The buggy address belongs to the object at ffff88804fb86e00
which belongs to the cache kmalloc-cg-64 of size 64
The buggy address is located 16 bytes inside of
64-byte region [ffff88804fb86e00, ffff88804fb86e40)
The buggy address belongs to the physical page:
page:ffffea00013ee180 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4fb86
memcg:ffff888079168a01
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea00025a99c0 dead000000000004 ffff888017442780
raw: 0000000000000000 0000000080200020 00000001ffffffff ffff888079168a01
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 11358, tgid 11358 (syz-executor), ts 1029966131356, free_ts 1029965684122
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559
prep_new_page mm/page_alloc.c:2566 [inline]
get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357
__alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657
alloc_slab_page+0x5d/0x160 mm/slub.c:1799
allocate_slab mm/slub.c:1944 [inline]
new_slab+0x87/0x2c0 mm/slub.c:1997
___slab_alloc+0xbc6/0x1240 mm/slub.c:3154
__slab_alloc mm/slub.c:3240 [inline]
slab_alloc_node mm/slub.c:3325 [inline]
__kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
kmalloc include/linux/slab.h:563 [inline]
alloc_fdtable+0xca/0x2c0 fs/file.c:147
dup_fd+0x782/0xa50 fs/file.c:346
copy_files+0x72/0xe0 kernel/fork.c:1641
copy_process+0x1835/0x4030 kernel/fork.c:2344
kernel_clone+0x24b/0x900 kernel/fork.c:2762
__do_sys_clone kernel/fork.c:2903 [inline]
__se_sys_clone kernel/fork.c:2887 [inline]
__x64_sys_clone+0x1a7/0x220 kernel/fork.c:2887
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1486 [inline]
free_pcp_prepare mm/page_alloc.c:1536 [inline]
free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508
__vunmap+0x856/0xa00 mm/vmalloc.c:2726
copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:884 [inline]
get_entries net/ipv6/netfilter/ip6_tables.c:1041 [inline]
do_ip6t_get_ctl+0xec0/0x11b0 net/ipv6/netfilter/ip6_tables.c:1679
nf_getsockopt+0x25e/0x280 net/netfilter/nf_sockopt.c:116
ipv6_getsockopt+0x222/0x2e0 net/ipv6/ipv6_sockglue.c:1512
__sys_getsockopt+0x1b0/0x230 net/socket.c:2331
__do_sys_getsockopt net/socket.c:2346 [inline]
__se_sys_getsockopt net/socket.c:2343 [inline]
__x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2343
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Memory state around the buggy address:
ffff88804fb86d00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff88804fb86d80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88804fb86e00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
^
ffff88804fb86e80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff88804fb86f00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
0: 89 7c 24 44 mov %edi,0x44(%rsp)
4: 0f b7 db movzwl %bx,%ebx
7: 48 c7 c7 00 07 8b 8a mov $0xffffffff8a8b0700,%rdi
e: e8 bf 90 de 08 call 0x8de90d2
13: 65 66 c7 05 a5 35 b4 movw $0x0,%gs:0x7eb435a5(%rip) # 0x7eb435c2
1a: 7e 00 00
1d: e8 80 73 39 00 call 0x3973a2
22: fb sti
23: 49 c7 c6 c0 a0 80 8c mov $0xffffffff8c80a0c0,%r14
* 2a: 89 5c 24 4c mov %ebx,0x4c(%rsp) <-- trapping instruction
2e: b8 ff ff ff ff mov $0xffffffff,%eax
33: 0f bc 44 24 4c bsf 0x4c(%rsp),%eax
38: 41 89 c5 mov %eax,%r13d
3b: 41 ff c5 inc %r13d
3e: 0f .byte 0xf
3f: 84 .byte 0x84