================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 96 at addr ffff8880402aaf90 by task syz.0.2749/14872 CPU: 1 PID: 14872 Comm: syz.0.2749 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: <#DB> 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+0x6bf/0x900 kernel/bpf/stackmap.c:271 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:362 [inline] bpf_get_stackid_pe+0x343/0x410 kernel/bpf/stackmap.c:331 bpf_prog_ebdd8313a69a195f+0x30/0x45 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:616 [inline] bpf_prog_run include/linux/filter.h:623 [inline] bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10584 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9720 perf_swevent_overflow kernel/events/core.c:9803 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9854 perf_bp_event+0x319/0x430 kernel/events/core.c:10781 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x23e/0x670 arch/x86/kernel/hw_breakpoint.c:586 notifier_call_chain+0x197/0x380 kernel/notifier.c:93 atomic_notifier_call_chain+0xda/0x180 kernel/notifier.c:231 notify_die+0x145/0x1a0 kernel/notifier.c:596 notify_debug+0x2e/0x50 arch/x86/kernel/traps.c:1042 exc_debug_kernel arch/x86/kernel/traps.c:1099 [inline] exc_debug+0xde/0x140 arch/x86/kernel/traps.c:1199 asm_exc_debug+0x1e/0x40 arch/x86/include/asm/idtentry.h:644 RIP: 0010:rep_movs_alternative+0x4a/0x90 arch/x86/lib/copy_user_64.S:71 Code: 75 f1 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 a4 c3 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01 RSP: 0018:ffffc90003337278 EFLAGS: 00050206 RAX: ffffffff8427e301 RBX: 0000000000000d24 RCX: 0000000000000a44 RDX: 0000000000000001 RSI: 0000200000000320 RDI: ffff888026192404 RBP: ffffc900033373d0 R08: ffff888026192e47 R09: 1ffff11004c325c8 R10: dffffc0000000000 R11: ffffed1004c325c9 R12: ffff888026192124 R13: 0000200000000040 R14: ffffc90003337c18 R15: 1ffff92000666f83 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:127 [inline] copyin lib/iov_iter.c:193 [inline] _copy_from_iter+0x24e/0x12e0 lib/iov_iter.c:390 copy_from_iter include/linux/uio.h:209 [inline] copy_from_iter_full include/linux/uio.h:216 [inline] tipc_msg_build+0x861/0xee0 net/tipc/msg.c:439 tipc_send_group_bcast+0x7d8/0xad0 net/tipc/socket.c:1129 __tipc_sendmsg+0x33c/0x2bb0 net/tipc/socket.c:1437 tipc_sendmsg+0x55/0x70 net/tipc/socket.c:1404 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x2df/0x420 net/socket.c:1160 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x46c/0x990 fs/read_write.c:584 ksys_write+0x150/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f247cf9cdd9 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:00007f247de50028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f247d215fa0 RCX: 00007f247cf9cdd9 RDX: 00000000000101d0 RSI: 0000200000000040 RDI: 0000000000000008 RBP: 00007f247d032d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f247d216038 R14: 00007f247d215fa0 R15: 00007fff153ea178 Allocated by task 14872: 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+0xb4/0x230 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+0x33a/0x4c0 kernel/bpf/stackmap.c:114 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5459 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 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 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 nf_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x788/0x910 net/netfilter/core.c:457 nf_register_net_hook+0xb2/0x190 net/netfilter/core.c:578 nf_register_net_hooks+0x44/0x1b0 net/netfilter/core.c:594 ebt_register_table+0xcec/0x10b0 net/bridge/netfilter/ebtables.c:1274 find_inlist_lock_noload+0x178/0x260 net/bridge/netfilter/ebtables.c:343 find_inlist_lock net/bridge/netfilter/ebtables.c:370 [inline] find_table_lock net/bridge/netfilter/ebtables.c:379 [inline] do_ebt_get_ctl+0x2d6/0x1d80 net/bridge/netfilter/ebtables.c:2468 nf_getsockopt+0x262/0x280 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x19f/0x230 net/ipv4/ip_sockglue.c:1790 do_sock_getsockopt+0x379/0x450 net/socket.c:2383 __sys_getsockopt net/socket.c:2412 [inline] __do_sys_getsockopt net/socket.c:2422 [inline] __se_sys_getsockopt net/socket.c:2419 [inline] __x64_sys_getsockopt+0x1d6/0x280 net/socket.c:2419 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to 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 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 nf_hook_entries_free net/netfilter/core.c:88 [inline] __nf_register_net_hook+0x788/0x910 net/netfilter/core.c:457 nf_register_net_hook+0xb2/0x190 net/netfilter/core.c:578 nf_register_net_hooks+0x44/0x1b0 net/netfilter/core.c:594 brnf_device_event+0x132/0x1d0 net/bridge/br_netfilter_hooks.c:1125 notifier_call_chain+0x197/0x380 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+0x16a5/0x1bb0 net/core/dev.c:10351 br_dev_newlink+0x27/0x100 net/bridge/br_netlink.c:1553 rtnl_newlink_create net/core/rtnetlink.c:3520 [inline] __rtnl_newlink net/core/rtnetlink.c:3740 [inline] rtnl_newlink+0x1542/0x20a0 net/core/rtnetlink.c:3753 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6475 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2200 __do_sys_sendto net/socket.c:2212 [inline] __se_sys_sendto net/socket.c:2208 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2208 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8880402aaf80 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff8880402aaf80, ffff8880402aafa8) The buggy address belongs to the physical page: page:ffffea000100aa80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x402aa memcg:ffff88807c410e01 ksm flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 ffffea0001348680 0000000000000003 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff88807c410e01 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 10738, tgid 10736 (syz.2.1558), ts 387667439829, free_ts 387663503166 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/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+0x19e/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa4/0x230 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 dev_map_init_map kernel/bpf/devmap.c:148 [inline] dev_map_alloc+0x1f6/0x4c0 kernel/bpf/devmap.c:167 map_create+0x877/0x12f0 kernel/bpf/syscall.c:1247 __sys_bpf+0x651/0x890 kernel/bpf/syscall.c:5459 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 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:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 vfree+0x1a6/0x320 mm/vmalloc.c:2868 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 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: ffff8880402aae80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880402aaf00: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff8880402aaf80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880402ab000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880402ab080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 75 f1 jne 0xfffffff3 2: c3 ret 3: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) a: 00 00 00 d: 0f 1f 00 nopl (%rax) 10: 48 8b 06 mov (%rsi),%rax 13: 48 89 07 mov %rax,(%rdi) 16: 48 83 c6 08 add $0x8,%rsi 1a: 48 83 c7 08 add $0x8,%rdi 1e: 83 e9 08 sub $0x8,%ecx 21: 74 df je 0x2 23: 83 f9 08 cmp $0x8,%ecx 26: 73 e8 jae 0x10 28: eb c9 jmp 0xfffffff3 * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: c3 ret 2d: 48 8b 06 mov (%rsi),%rax 30: 48 89 07 mov %rax,(%rdi) 33: 48 8d 47 08 lea 0x8(%rdi),%rax 37: 48 83 e0 f8 and $0xfffffffffffffff8,%rax 3b: 48 29 f8 sub %rdi,%rax 3e: 48 rex.W 3f: 01 .byte 0x1