================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 72 at addr ffff88802be24890 by task syz.0.221/5133 CPU: 0 PID: 5133 Comm: syz.0.221 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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_ee9fdca00c0e1e15+0x28/0x3d bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x6d1/0x790 kernel/events/core.c:10321 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 do_perf_sw_event kernel/events/core.c:9743 [inline] ___perf_sw_event+0x498/0x6d0 kernel/events/core.c:9774 __perf_sw_event+0x135/0x260 kernel/events/core.c:9786 perf_sw_event include/linux/perf_event.h:1254 [inline] do_user_addr_fault+0x497/0xb20 arch/x86/mm/fault.c:1284 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] RIP: 0010:strncpy_from_user+0x148/0x340 lib/strncpy_from_user.c:139 Code: 00 00 00 4c 89 e6 e8 77 2d 45 fd 49 83 fc 07 0f 86 9a 00 00 00 4c 89 74 24 08 48 c7 44 24 10 f8 ff ff ff 45 31 ed 4c 89 3c 24 <4f> 8b 3c 2f 48 b8 ff fe fe fe fe fe fe fe 49 8d 2c 07 4d 89 fe 49 RSP: 0018:ffffc90003307bf0 EFLAGS: 00050246 RAX: ffffffff843d0489 RBX: ffff888027aba220 RCX: ffff88807a591e00 RDX: 0000000000000002 RSI: 0000000000000fe0 RDI: 0000000000000007 RBP: 0000000000000000 R08: ffffea00009eae07 R09: 1ffffd400013d5c0 R10: dffffc0000000000 R11: fffff9400013d5c1 R12: 0000000000000fe0 R13: 0000000000000000 R14: 0000000000000fe0 R15: 0000000000000000 getname_flags+0xf2/0x500 fs/namei.c:150 user_path_at_empty+0x28/0x60 fs/namei.c:2912 user_path_at include/linux/namei.h:57 [inline] bpf_obj_do_get kernel/bpf/inode.c:506 [inline] bpf_obj_get_user+0xb6/0x480 kernel/bpf/inode.c:541 __sys_bpf+0x532/0x780 kernel/bpf/syscall.c:5038 __do_sys_bpf kernel/bpf/syscall.c:5136 [inline] __se_sys_bpf kernel/bpf/syscall.c:5134 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5134 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 RIP: 0033:0x7fc93839e019 Code: 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 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc93918d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fc938625fa0 RCX: 00007fc93839e019 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007fc93843500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc938626038 R14: 00007fc938625fa0 R15: 00007ffd17f4f758 Allocated by task 5133: 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+0xb2/0x240 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+0x386/0x510 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x524/0xff0 kernel/bpf/syscall.c:1149 __sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5014 __do_sys_bpf kernel/bpf/syscall.c:5136 [inline] __se_sys_bpf kernel/bpf/syscall.c:5134 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5134 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/0x950 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 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x703/0xba0 net/core/net_namespace.c:640 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 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/0x950 kernel/rcu/tree.c:2849 nf_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x787/0x910 net/netfilter/core.c:445 nf_register_net_hook+0xae/0x190 net/netfilter/core.c:566 nf_register_net_hooks+0x40/0x1a0 net/netfilter/core.c:582 ipvlan_register_nf_hook drivers/net/ipvlan/ipvlan_l3s.c:138 [inline] ipvlan_l3s_register+0x130/0x1d0 drivers/net/ipvlan/ipvlan_l3s.c:210 ipvlan_set_port_mode+0x1a1/0x3f0 drivers/net/ipvlan/ipvlan_main.c:34 ipvlan_link_new+0x732/0xae0 drivers/net/ipvlan/ipvlan_main.c:633 rtnl_newlink_create net/core/rtnetlink.c:3436 [inline] __rtnl_newlink net/core/rtnetlink.c:3656 [inline] rtnl_newlink+0x14b3/0x1f90 net/core/rtnetlink.c:3669 rtnetlink_rcv_msg+0x863/0xfb0 net/core/rtnetlink.c:6166 netlink_rcv_skb+0x1ef/0x440 net/netlink/af_netlink.c:2516 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x7ad/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] __sys_sendto+0x497/0x650 net/socket.c:2153 __do_sys_sendto net/socket.c:2165 [inline] __se_sys_sendto net/socket.c:2161 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2161 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 The buggy address belongs to the object at ffff88802be24880 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88802be24880, ffff88802be248c0) The buggy address belongs to the physical page: page:ffffea0000af8900 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802be24e80 pfn:0x2be24 memcg:ffff88807c0f6601 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00016cb240 dead000000000007 ffff888017442780 raw: ffff88802be24e80 000000008020001f 00000001ffffffff ffff88807c0f6601 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x16cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY), pid 3644, tgid 3644 (udevd), ts 28122787359, free_ts 28119821984 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 alloc_slab_page+0x5d/0x180 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2d0 mm/slub.c:1997 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] inotify_handle_inode_event+0x17c/0x4e0 fs/notify/inotify/inotify_fsnotify.c:96 fsnotify_handle_inode_event fs/notify/fsnotify.c:282 [inline] fsnotify_handle_event fs/notify/fsnotify.c:311 [inline] send_to_group fs/notify/fsnotify.c:385 [inline] fsnotify+0x1746/0x1df0 fs/notify/fsnotify.c:591 __fsnotify_parent+0x683/0x820 fs/notify/fsnotify.c:248 notify_change+0xce6/0xf90 fs/attr.c:504 chmod_common+0x253/0x400 fs/open.c:606 do_fchmodat+0xd4/0x1a0 fs/open.c:645 __do_sys_chmod fs/open.c:663 [inline] __se_sys_chmod fs/open.c:661 [inline] __x64_sys_chmod+0x5c/0x70 fs/open.c:661 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x188/0x1e0 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kernfs_fop_write_iter+0x154/0x520 fs/kernfs/file.c:329 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x482/0x9a0 fs/read_write.c:584 ksys_write+0x14d/0x260 fs/read_write.c:637 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: ffff88802be24780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802be24800: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88802be24880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802be24900: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802be24980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 4c 89 e6 add %cl,-0x1a(%rcx,%rcx,4) 6: e8 77 2d 45 fd call 0xfd452d82 b: 49 83 fc 07 cmp $0x7,%r12 f: 0f 86 9a 00 00 00 jbe 0xaf 15: 4c 89 74 24 08 mov %r14,0x8(%rsp) 1a: 48 c7 44 24 10 f8 ff movq $0xfffffffffffffff8,0x10(%rsp) 21: ff ff 23: 45 31 ed xor %r13d,%r13d 26: 4c 89 3c 24 mov %r15,(%rsp) * 2a: 4f 8b 3c 2f mov (%r15,%r13,1),%r15 <-- trapping instruction 2e: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax 35: fe fe fe 38: 49 8d 2c 07 lea (%r15,%rax,1),%rbp 3c: 4d 89 fe mov %r15,%r14 3f: 49 rex.WB