================================================================== BUG: KASAN: slab-out-of-bounds in stack_map_get_build_id_offset+0x988/0x9b0 kernel/bpf/stackmap.c:147 Write of size 4 at addr ffff88813124c330 by task syz.0.170/1058 CPU: 0 PID: 1058 Comm: syz.0.170 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report_generic.c:355 stack_map_get_build_id_offset+0x988/0x9b0 kernel/bpf/stackmap.c:147 __bpf_get_stackid+0x5ac/0x960 kernel/bpf/stackmap.c:250 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334 bpf_prog_2414a5d5030ea31b+0x21/0x25 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x521/0x5e0 kernel/events/core.c:10273 __perf_event_overflow+0x458/0x640 kernel/events/core.c:9448 perf_swevent_overflow kernel/events/core.c:9531 [inline] perf_swevent_event+0x243/0x440 kernel/events/core.c:9582 do_perf_sw_event kernel/events/core.c:9695 [inline] ___perf_sw_event+0x3bf/0x500 kernel/events/core.c:9726 __perf_sw_event+0x134/0x270 kernel/events/core.c:9738 perf_sw_event include/linux/perf_event.h:1250 [inline] do_user_addr_fault+0xfe9/0x1030 arch/x86/mm/fault.c:1285 handle_page_fault arch/x86/mm/fault.c:1464 [inline] exc_page_fault+0x51/0xb0 arch/x86/mm/fault.c:1517 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:copy_user_enhanced_fast_string+0x27/0x40 Code: ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 f3 a4 31 c0 0f 01 ca c3 89 ca eb 0a 90 90 90 90 90 90 90 90 90 90 83 f8 12 74 0a 89 d1 a4 89 c8 0f 01 ca c3 89 d0 0f 01 ca c3 01 ca eb e7 90 90 90 90 RSP: 0018:ffffc9000df0fa68 EFLAGS: 00050287 RAX: 000000000000000e RBX: 0000000000000004 RCX: 0000000000000004 RDX: 0000000000000004 RSI: 0000000700660000 RDI: ffffc9000df0fbb0 RBP: ffffc9000df0fa90 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52001be1f76 R12: 00007fffffffeffc R13: dffffc0000000000 R14: ffffc9000df0fbb0 R15: 0000000700660000 copy_from_user include/linux/uaccess.h:161 [inline] dev_ethtool+0xc2/0x1330 net/ethtool/ioctl.c:3079 dev_ioctl+0x459/0xcf0 net/core/dev_ioctl.c:510 sock_do_ioctl+0x252/0x330 net/socket.c:1206 sock_ioctl+0x475/0x700 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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: 0033:0x7faaa519e159 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:00007faaa610f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007faaa5426090 RCX: 00007faaa519e159 RDX: 0000200000000080 RSI: 0000000000008946 RDI: 000000000000000c RBP: 00007faaa523506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faaa5426128 R14: 00007faaa5426090 R15: 00007fff9787b888 Allocated by task 1058: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:380 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389 kasan_kmalloc include/linux/kasan.h:212 [inline] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc_node+0xb2/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x4b/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x8a/0x1e0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x398/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x467/0xcf0 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4988 __do_sys_bpf kernel/bpf/syscall.c:5110 [inline] __se_sys_bpf kernel/bpf/syscall.c:5108 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5108 x64_sys_call+0x488/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322 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+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 __call_rcu_common kernel/rcu/tree.c:2807 [inline] call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926 __qdisc_destroy+0x187/0x290 net/sched/sch_generic.c:1083 qdisc_put net/sched/sch_generic.c:1103 [inline] shutdown_scheduler_queue net/sched/sch_generic.c:1156 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2504 [inline] dev_shutdown+0x198/0x580 net/sched/sch_generic.c:1461 unregister_netdevice_many+0x9a0/0x1910 net/core/dev.c:10996 unregister_netdevice_queue+0x2e1/0x320 net/core/dev.c:10936 unregister_netdevice include/linux/netdevice.h:3109 [inline] __tun_detach+0xc9d/0x1450 drivers/net/tun.c:685 tun_detach drivers/net/tun.c:701 [inline] tun_chr_close+0x92/0x140 drivers/net/tun.c:3495 __fput+0x1fd/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88813124c000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 816 bytes inside of 1024-byte region [ffff88813124c000, ffff88813124c400) The buggy address belongs to the physical page: page:ffffea0004c49200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x131248 head:ffffea0004c49200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea0004c4a000 dead000000000002 ffff888100043080 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 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 289, tgid 289 (syz-executor), ts 22129151157, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3e0 mm/slub.c:2020 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423 kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] new_nbp+0x192/0x450 net/bridge/br_if.c:432 br_add_if+0x28c/0xe70 net/bridge/br_if.c:600 br_add_slave+0x2c/0x40 net/bridge/br_device.c:388 do_set_master net/core/rtnetlink.c:2634 [inline] do_setlink+0xdad/0x2a10 net/core/rtnetlink.c:2844 __rtnl_newlink net/core/rtnetlink.c:3612 [inline] rtnl_newlink+0x17d7/0x20d0 net/core/rtnetlink.c:3659 rtnetlink_rcv_msg+0xb28/0xde0 net/core/rtnetlink.c:6154 page_owner free stack trace missing Memory state around the buggy address: ffff88813124c200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88813124c280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88813124c300: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ^ ffff88813124c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88813124c400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: ca eb 20 lret $0x20eb 3: 0f 01 cb stac 6: 83 fa 40 cmp $0x40,%edx 9: 72 38 jb 0x43 b: 89 d1 mov %edx,%ecx d: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) f: 31 c0 xor %eax,%eax 11: 0f 01 ca clac 14: c3 ret 15: 89 ca mov %ecx,%edx 17: eb 0a jmp 0x23 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 83 f8 12 cmp $0x12,%eax 26: 74 0a je 0x32 28: 89 d1 mov %edx,%ecx * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: 89 c8 mov %ecx,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 89 d0 mov %edx,%eax 34: 0f 01 ca clac 37: c3 ret 38: 01 ca add %ecx,%edx 3a: eb e7 jmp 0x23 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop