==================================================================
BUG: KASAN: slab-use-after-free in llc_conn_ac_send_sabme_cmd_p_set_x+0x38a/0x420 net/llc/llc_c_ac.c:782
Read of size 1 at addr ffff888054536010 by task ipvs-e:5:0/10168
CPU: 0 UID: 0 PID: 10168 Comm: ipvs-e:5:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
llc_conn_ac_send_sabme_cmd_p_set_x+0x38a/0x420 net/llc/llc_c_ac.c:782
llc_exec_conn_trans_actions net/llc/llc_conn.c:437 [inline]
llc_conn_service net/llc/llc_conn.c:362 [inline]
llc_conn_state_process+0x4fb/0x1380 net/llc/llc_conn.c:66
llc_process_tmr_ev net/llc/llc_c_ac.c:1442 [inline]
llc_conn_tmr_common_cb+0x34a/0x780 net/llc/llc_c_ac.c:1325
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:finish_task_switch+0x413/0xc60 kernel/sched/core.c:5361
Code: 04 00 00 41 c7 84 24 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 97 15 46 0a e8 92 c9 39 00 fb 4c 8b 65 c8 <49> 8d bc 24 08 17 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0
RSP: 0018:ffffc9000d10f7e0 EFLAGS: 00000202
RAX: 000000000000575b RBX: ffff8880b863c2a0 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8e258a05 RDI: ffffffff8c4cd780
RBP: ffffc9000d10f830 R08: ffffffff90589537 R09: 1ffffffff20b12a6
R10: dffffc0000000000 R11: fffffbfff20b12a7 R12: ffff888067d99f40
R13: ffff8880b863c268 R14: dffffc0000000000 R15: 1ffff110170c7854
context_switch kernel/sched/core.c:5513 [inline]
__schedule+0x17dc/0x5630 kernel/sched/core.c:7239
__schedule_loop kernel/sched/core.c:7316 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7331
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
ip_vs_estimation_kthread+0x29ef/0x3950 net/netfilter/ipvs/ip_vs_est.c:216
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 10732:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x331/0x660 mm/slub.c:5489
_kmalloc_noprof include/linux/slab.h:988 [inline]
_kzalloc_noprof include/linux/slab.h:1309 [inline]
llc_sap_alloc net/llc/llc_core.c:29 [inline]
llc_sap_open+0xe1/0x3b0 net/llc/llc_core.c:96
llc_ui_autobind+0x1f1/0x560 net/llc/af_llc.c:301
llc_ui_connect+0x1d7/0xd50 net/llc/af_llc.c:498
connect_socket net/socket.c:2141 [inline]
__sys_connect_file net/socket.c:2166 [inline]
__sys_connect+0x316/0x450 net/socket.c:2183
__do_sys_connect net/socket.c:2189 [inline]
__se_sys_connect net/socket.c:2186 [inline]
__x64_sys_connect+0x7a/0x90 net/socket.c:2186
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 10743:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2677 [inline]
__rcu_free_sheaf_prepare+0x12d/0x2a0 mm/slub.c:2928
rcu_free_sheaf+0x31/0x200 mm/slub.c:5978
rcu_do_batch kernel/rcu/tree.c:2645 [inline]
rcu_core+0x794/0x10b0 kernel/rcu/tree.c:2897
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
The buggy address belongs to the object at ffff888054536000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 16 bytes inside of
freed 2048-byte region [ffff888054536000, ffff888054536800)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888054531000 pfn:0x54530
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88801b003000 ffffea0001e3ec10 ffffea0000ccca10
raw: ffff888054531000 0000000800080006 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801b003000 ffffea0001e3ec10 ffffea0000ccca10
head: ffff888054531000 0000000800080006 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
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), pid 10, tgid 10 (kworker/0:1), ts 93981543177, free_ts 93565719554
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0x21fe/0x2270 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3266 [inline]
allocate_slab+0x79/0x5e0 mm/slub.c:3380
new_slab mm/slub.c:3426 [inline]
refill_objects+0x2d5/0x350 mm/slub.c:7310
refill_sheaf mm/slub.c:2804 [inline]
__pcs_replace_empty_main+0x2c3/0x6b0 mm/slub.c:4675
alloc_from_pcs mm/slub.c:4773 [inline]
slab_alloc_node mm/slub.c:4905 [inline]
__do_kmalloc_node mm/slub.c:5333 [inline]
__kmalloc_node_track_caller_noprof+0x55b/0x740 mm/slub.c:5471
kmalloc_reserve net/core/skbuff.c:637 [inline]
__alloc_skb+0x2c1/0x7a0 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
mld_newpack+0x165/0xcb0 net/ipv6/mcast.c:1790
add_grhead net/ipv6/mcast.c:1901 [inline]
add_grec+0x119f/0x19d0 net/ipv6/mcast.c:2040
mld_send_initial_cr+0x288/0x550 net/ipv6/mcast.c:2285
mld_dad_work+0x3d/0x480 net/ipv6/mcast.c:2311
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
page last free pid 5852 tgid 5848 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
free_pages_prepare+0x960/0xa60 mm/page_alloc.c:1451
__free_contig_range_common+0x174/0x340 mm/page_alloc.c:6897
__free_contig_range mm/page_alloc.c:6942 [inline]
free_pages_bulk+0x48/0x120 mm/page_alloc.c:5257
vm_area_free_pages mm/vmalloc.c:3461 [inline]
vfree+0x226/0x4a0 mm/vmalloc.c:3510
cleanup_match net/ipv6/netfilter/ip6_tables.c:477 [inline]
cleanup_entry+0x15f/0x360 net/ipv6/netfilter/ip6_tables.c:661
translate_table+0x1e26/0x2040 net/ipv6/netfilter/ip6_tables.c:744
do_replace net/ipv6/netfilter/ip6_tables.c:1152 [inline]
do_ip6t_set_ctl+0xa5c/0xe30 net/ipv6/netfilter/ip6_tables.c:1643
nf_setsockopt+0x26f/0x290 net/netfilter/nf_sockopt.c:101
rawv6_setsockopt+0x276/0x5e0 net/ipv6/raw.c:1048
do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2397
__sys_setsockopt net/socket.c:2422 [inline]
__do_sys_setsockopt net/socket.c:2428 [inline]
__se_sys_setsockopt net/socket.c:2425 [inline]
__x64_sys_setsockopt+0x13d/0x1b0 net/socket.c:2425
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff888054535f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888054535f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888054536000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888054536080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888054536100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 00 00 add %al,(%rax)
2: 41 c7 84 24 20 0e 00 movl $0x0,0xe20(%r12)
9: 00 00 00 00 00
e: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
13: 49 83 c4 48 add $0x48,%r12
17: 4c 89 e7 mov %r12,%rdi
1a: e8 97 15 46 0a call 0xa4615b6
1f: e8 92 c9 39 00 call 0x39c9b6
24: fb sti
25: 4c 8b 65 c8 mov -0x38(%rbp),%r12
* 29: 49 8d bc 24 08 17 00 lea 0x1708(%r12),%rdi <-- trapping instruction
30: 00
31: 48 89 f8 mov %rdi,%rax
34: 48 c1 e8 03 shr $0x3,%rax
38: 42 0f b6 04 30 movzbl (%rax,%r14,1),%eax
3d: 84 c0 test %al,%al