================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 96 at addr ffff8881316b3810 by task syz.3.449/1895 CPU: 0 PID: 1895 Comm: syz.3.449 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 memcpy+0x44/0x70 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:365 [inline] bpf_get_stackid_pe+0x2ee/0x400 kernel/bpf/stackmap.c:334 bpf_prog_a448e89f4c9ad9d1+0x28/0x42 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:fault_in_readable+0xd5/0x150 mm/gup.c:1915 Code: e1 4a c7 ff 4d 89 f4 49 81 cc ff 0f 00 00 4d 89 f7 49 01 dc 49 81 e4 00 f0 ff ff 4d 39 e6 77 3d e8 c0 4a c7 ff 4d 39 e7 74 40 <41> 8a 07 88 45 df 49 81 c7 00 10 00 00 4d 39 e7 74 07 e8 a4 4a c7 RSP: 0018:ffffc90000d17a28 EFLAGS: 00050287 RAX: ffffffff81aa0a60 RBX: 0000000000001000 RCX: ffff888116080000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000d17a50 R08: ffff888116080000 R09: 0000000000000002 R10: 0000000000000006 R11: 0000000000000000 R12: 0000200000131000 R13: dffffc0000000000 R14: 0000200000130000 R15: 0000200000130000 fault_in_iov_iter_readable+0xc3/0x310 lib/iov_iter.c:356 generic_perform_write+0x212/0x740 mm/filemap.c:3905 __generic_file_write_iter+0x17a/0x230 mm/filemap.c:4014 generic_file_write_iter+0xae/0x310 mm/filemap.c:4043 call_write_iter include/linux/fs.h:2282 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x5ef/0xd00 fs/read_write.c:584 ksys_write+0x14a/0x260 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 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: 0033:0x7fb822f9ce59 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:00007fb823de0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb823215fa0 RCX: 00007fb822f9ce59 RDX: 00000000002a979d RSI: 0000200000000000 RDI: 000000000000000e RBP: 00007fb823032e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb823216038 R14: 00007fb823215fa0 R15: 00007ffeb0295bc8 Allocated by task 1896: 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 The buggy address belongs to the object at ffff8881316b3800 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff8881316b3800, ffff8881316b3840) The buggy address belongs to the physical page: page:ffffea0004c5acc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1316b3 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004cdbbc0 dead000000000004 ffff888100042780 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 288, tgid 288 (syz-executor), ts 30294564092, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2672 prep_new_page+0x1c/0x110 mm/page_alloc.c:2679 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4586 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5930 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] netdev_name_node_alloc net/core/dev.c:260 [inline] netdev_name_node_head_alloc net/core/dev.c:274 [inline] register_netdevice+0x2ea/0x1550 net/core/dev.c:10130 veth_newlink+0x66a/0xd60 drivers/net/veth.c:1745 rtnl_newlink_create net/core/rtnetlink.c:3425 [inline] __rtnl_newlink net/core/rtnetlink.c:3645 [inline] rtnl_newlink+0x14dc/0x20d0 net/core/rtnetlink.c:3658 rtnetlink_rcv_msg+0xb28/0xde0 net/core/rtnetlink.c:6153 netlink_rcv_skb+0x200/0x450 net/netlink/af_netlink.c:2521 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6171 page_owner free stack trace missing Memory state around the buggy address: ffff8881316b3700: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc ffff8881316b3780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8881316b3800: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881316b3880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881316b3900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 4a c7 rex.WX (bad) 2: ff 4d 89 decl -0x77(%rbp) 5: f4 hlt 6: 49 81 cc ff 0f 00 00 or $0xfff,%r12 d: 4d 89 f7 mov %r14,%r15 10: 49 01 dc add %rbx,%r12 13: 49 81 e4 00 f0 ff ff and $0xfffffffffffff000,%r12 1a: 4d 39 e6 cmp %r12,%r14 1d: 77 3d ja 0x5c 1f: e8 c0 4a c7 ff call 0xffc74ae4 24: 4d 39 e7 cmp %r12,%r15 27: 74 40 je 0x69 * 29: 41 8a 07 mov (%r15),%al <-- trapping instruction 2c: 88 45 df mov %al,-0x21(%rbp) 2f: 49 81 c7 00 10 00 00 add $0x1000,%r15 36: 4d 39 e7 cmp %r12,%r15 39: 74 07 je 0x42 3b: e8 .byte 0xe8 3c: a4 movsb %ds:(%rsi),%es:(%rdi) 3d: 4a rex.WX 3e: c7 .byte 0xc7