================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 Write of size 32 at addr ffff88806045cd60 by task syz.7.316/7755 CPU: 0 PID: 7755 Comm: syz.7.316 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x241/0x290 mm/kasan/generic.c:187 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:374 [inline] bpf_get_stackid_pe+0x2f0/0x410 kernel/bpf/stackmap.c:331 bpf_prog_620e6a2847f43590+0x33/0x48 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:606 [inline] bpf_prog_run include/linux/filter.h:624 [inline] bpf_overflow_handler+0x43f/0x510 kernel/events/core.c:10576 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712 perf_swevent_overflow kernel/events/core.c:9795 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9846 do_perf_sw_event kernel/events/core.c:9959 [inline] ___perf_sw_event+0x4ab/0x730 kernel/events/core.c:9990 __perf_sw_event+0x139/0x270 kernel/events/core.c:10002 perf_sw_event include/linux/perf_event.h:1442 [inline] do_user_addr_fault+0x1242/0x12d0 arch/x86/mm/fault.c:1278 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7ffdaabbaa21 Code: 48 89 c2 eb a7 4c 29 d2 48 0f ba e2 3e 0f 82 ad 00 00 00 48 bf ff ff ff ff ff ff ff 7f 48 21 fa 49 0f af d1 48 01 c2 48 d3 ea <48> 89 55 c0 31 c0 48 81 fa 00 ca 9a 3b 72 1c 31 c9 48 81 c2 00 36 RSP: 002b:00007f9d3fef3ff0 EFLAGS: 00010202 RAX: 00022b0a4567e30e RBX: 00007ffdaabb60b0 RCX: 0000000000000018 RDX: 0000000002f2d158 RSI: 00007f9d3fef40b0 RDI: 7fffffffffffffff RBP: 00007f9d3fef4030 R08: 00000000000001f8 R09: 0000000000745d1e R10: 000001077d283583 R11: 000000000001348a R12: 0000000000000010 R13: 00007f9d3f226038 R14: 00007ffdaabb6080 R15: 000000000001348a Allocated by task 7755: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node+0xb6/0x240 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:303 [inline] bpf_map_area_alloc+0x5e/0x110 kernel/bpf/syscall.c:316 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x32b/0x4b0 kernel/bpf/stackmap.c:114 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5460 __do_sys_bpf kernel/bpf/syscall.c:5582 [inline] __se_sys_bpf kernel/bpf/syscall.c:5580 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5580 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x780 kernel/rcu/tree.c:3452 drop_sysctl_table+0x394/0x540 fs/proc/proc_sysctl.c:1515 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1536 mpls_dev_sysctl_unregister net/mpls/af_mpls.c:1431 [inline] mpls_dev_notify+0x679/0x7a0 net/mpls/af_mpls.c:1651 notifier_call_chain+0x18f/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2077 [inline] call_netdevice_notifiers net/core/dev.c:2091 [inline] dev_change_name+0x608/0x8e0 net/core/dev.c:1313 do_setlink+0x925/0x3f40 net/core/rtnetlink.c:2897 __rtnl_newlink net/core/rtnetlink.c:3715 [inline] rtnl_newlink+0x1848/0x2170 net/core/rtnetlink.c:3762 rtnetlink_rcv_msg+0x843/0xf90 net/core/rtnetlink.c:6484 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x7b1/0x930 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88806045cd00 which belongs to the cache kmalloc-cg-128 of size 128 The buggy address is located 96 bytes inside of allocated 120-byte region [ffff88806045cd00, ffff88806045cd78) The buggy address belongs to the physical page: page:ffffea0001811700 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6045c memcg:ffff88802e6a7501 ksm flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4dc80 ffffea00017c8ec0 dead000000000003 raw: 0000000000000000 0000000080100010 00000001ffffffff ffff88802e6a7501 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 5932, tgid 5932 (syz-executor), ts 392386076182, free_ts 392211483389 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa7/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] __register_sysctl_table+0x71/0x1210 fs/proc/proc_sysctl.c:1373 mpls_dev_sysctl_register+0x207/0x2f0 net/mpls/af_mpls.c:1406 mpls_add_dev net/mpls/af_mpls.c:1462 [inline] mpls_dev_notify+0x357/0x7a0 net/mpls/af_mpls.c:1602 notifier_call_chain+0x18f/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2077 [inline] call_netdevice_notifiers net/core/dev.c:2091 [inline] register_netdevice+0x1670/0x1ba0 net/core/dev.c:10351 register_vlan_dev+0x3a4/0x820 net/8021q/vlan.c:180 vlan_newlink+0x43a/0x580 net/8021q/vlan_netlink.c:195 rtnl_newlink_create net/core/rtnetlink.c:3529 [inline] __rtnl_newlink net/core/rtnetlink.c:3749 [inline] rtnl_newlink+0x15a0/0x2170 net/core/rtnetlink.c:3762 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1182 [inline] __free_pages_ok+0x994/0xad0 mm/page_alloc.c:1312 free_large_kmalloc+0x101/0x1b0 mm/slab_common.c:984 wg_destruct+0x285/0x310 drivers/net/wireguard/device.c:266 netdev_run_todo+0xbe7/0xdb0 net/core/dev.c:10631 default_device_exit_batch+0x967/0xa00 net/core/dev.c:11747 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x792/0xbb0 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff88806045cc00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ffff88806045cc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806045cd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc ^ ffff88806045cd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806045ce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================