================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6bf/0x900 kernel/bpf/stackmap.c:271 Write of size 56 at addr ffff888030150a10 by task syz.1.5819/28899 CPU: 0 PID: 28899 Comm: syz.1.5819 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+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_a448e89f4c9ad9d1+0x30/0x4a 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 do_perf_sw_event kernel/events/core.c:9967 [inline] ___perf_sw_event+0x4a7/0x730 kernel/events/core.c:9998 __perf_sw_event+0x139/0x270 kernel/events/core.c:10010 perf_sw_event include/linux/perf_event.h:1442 [inline] do_user_addr_fault+0x123e/0x12c0 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: 0010:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] RIP: 0010:strncpy_from_user+0xff/0x2d0 lib/strncpy_from_user.c:139 Code: 4c 89 ee e8 d3 65 2a fd 49 83 fd 07 0f 86 a1 00 00 00 4c 89 74 24 08 48 c7 44 24 10 f8 ff ff ff 45 31 e4 4c 89 3c 24 49 89 de <4f> 8b 3c 27 48 b8 ff fe fe fe fe fe fe fe 49 8d 1c 07 4c 89 fd 48 RSP: 0018:ffffc90004de7b50 EFLAGS: 00050246 RAX: ffffffff845cc06d RBX: ffffc90004de7c70 RCX: ffff8880694b1e00 RDX: 0000000000000000 RSI: 000000000000007f RDI: 0000000000000007 RBP: ffffc90004de7d70 R08: ffff8880694b1e00 R09: 0000000000000003 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 R13: 000000000000007f R14: ffffc90004de7c70 R15: 0000000000000000 bpf_prog_load+0xcea/0x1670 kernel/bpf/syscall.c:2714 __sys_bpf+0x5ba/0x890 kernel/bpf/syscall.c:5477 __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 RIP: 0033:0x7fd42ef9c819 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:00007fd42fea5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fd42f216090 RCX: 00007fd42ef9c819 RDX: 0000000000000094 RSI: 0000200000000080 RDI: 0000000000000005 RBP: 00007fd42f032c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd42f216128 R14: 00007fd42f216090 R15: 00007ffe1fe35ee8 Allocated by task 28898: 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 ip6t_register_table+0x543/0x7e0 net/ipv6/netfilter/ip6_tables.c:1787 ip6table_mangle_table_init+0x41/0x60 net/ipv6/netfilter/ip6table_mangle.c:84 xt_find_table_lock+0x306/0x3e0 net/netfilter/x_tables.c:1282 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1307 get_info net/ipv6/netfilter/ip6_tables.c:979 [inline] do_ip6t_get_ctl+0x717/0x1210 net/ipv6/netfilter/ip6_tables.c:1668 nf_getsockopt+0x262/0x280 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x226/0x2e0 net/ipv6/ipv6_sockglue.c:1499 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 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 The buggy address belongs to the object at ffff888030150a00 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff888030150a00, ffff888030150a28) The buggy address belongs to the physical page: page:ffffea0000c05400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30150 memcg:ffff88802b903c01 ksm flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 ffffea0001a63f00 dead000000000003 raw: 0000000000000000 0000000080200020 00000001ffffffff ffff88802b903c01 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 9628, tgid 9627 (syz.1.1040), ts 328229398131, free_ts 327976090480 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 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] alloc_fdtable+0xca/0x2c0 fs/file.c:147 dup_fd+0x786/0xa50 fs/file.c:346 copy_files+0xc3/0x120 kernel/fork.c:1795 copy_process+0x15ab/0x3d80 kernel/fork.c:2495 kernel_clone+0x24b/0x8a0 kernel/fork.c:2915 __do_sys_clone kernel/fork.c:3058 [inline] __se_sys_clone kernel/fork.c:3042 [inline] __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3042 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_list+0xbe/0x860 mm/page_alloc.c:2504 release_pages+0x1f7a/0x2200 mm/swap.c:1022 tlb_batch_pages_flush mm/mmu_gather.c:99 [inline] tlb_flush_mmu_free mm/mmu_gather.c:294 [inline] tlb_flush_mmu+0x379/0x510 mm/mmu_gather.c:301 tlb_finish_mmu+0xf9/0x220 mm/mmu_gather.c:425 exit_mmap+0x428/0xb90 mm/mmap.c:3315 __mmput+0x118/0x3c0 kernel/fork.c:1356 exit_mm+0x1f2/0x2c0 kernel/exit.c:569 do_exit+0x8dd/0x2460 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 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 Memory state around the buggy address: ffff888030150900: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff888030150980: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc >ffff888030150a00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff888030150a80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff888030150b00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 4c 89 ee mov %r13,%rsi 3: e8 d3 65 2a fd call 0xfd2a65db 8: 49 83 fd 07 cmp $0x7,%r13 c: 0f 86 a1 00 00 00 jbe 0xb3 12: 4c 89 74 24 08 mov %r14,0x8(%rsp) 17: 48 c7 44 24 10 f8 ff movq $0xfffffffffffffff8,0x10(%rsp) 1e: ff ff 20: 45 31 e4 xor %r12d,%r12d 23: 4c 89 3c 24 mov %r15,(%rsp) 27: 49 89 de mov %rbx,%r14 * 2a: 4f 8b 3c 27 mov (%r15,%r12,1),%r15 <-- trapping instruction 2e: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax 35: fe fe fe 38: 49 8d 1c 07 lea (%r15,%rax,1),%rbx 3c: 4c 89 fd mov %r15,%rbp 3f: 48 rex.W