================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 120 at addr ffff8881321cf190 by task syz.1.546/2548 CPU: 0 PID: 2548 Comm: syz.1.546 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 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 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_fa73c8c086b491e8+0x21/0x31 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x3d0/0x5e0 kernel/events/core.c:10238 __perf_event_overflow+0x437/0x620 kernel/events/core.c:9448 perf_swevent_hrtimer+0x400/0x5b0 kernel/events/core.c:10879 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x3d5/0xa00 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3c7/0x8c0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x11e/0x440 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:mutex_unlock+0x0/0x230 kernel/locking/mutex.c:558 Code: 1c ff ff ff 66 0f 1f 44 00 00 55 48 89 e5 be 02 00 00 00 e8 c2 12 00 00 5d c3 90 90 90 90 90 90 90 90 90 90 90 b8 c9 ff ad 1b <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 83 ec 60 49 RSP: 0018:ffffc9000e14f730 EFLAGS: 00000283 RAX: ffffffff81a69449 RBX: 0000000000000016 RCX: 0000000000080000 RDX: ffffc900012d9000 RSI: 0000000000010b0f RDI: ffffffff87253820 RBP: ffffc9000e14f818 R08: ffffc90000743af7 R09: 1ffff920000e875e R10: dffffc0000000000 R11: fffff520000e875f R12: 0000000000000016 R13: ffff88810b2e6a88 R14: ffff88810b2e6a00 R15: 0000000000000016 __alloc_percpu+0x24/0x30 mm/percpu.c:1950 alloc_vfsmnt+0x106/0x4a0 fs/namespace.c:223 clone_mnt+0x6d/0xd10 fs/namespace.c:1109 copy_tree+0x3e9/0x7e0 fs/namespace.c:1928 copy_mnt_ns+0x180/0x940 fs/namespace.c:3518 create_new_namespaces+0xcf/0x660 kernel/nsproxy.c:78 copy_namespaces+0x1d1/0x220 kernel/nsproxy.c:178 copy_process+0x1303/0x3510 kernel/fork.c:2478 kernel_clone+0x22f/0x820 kernel/fork.c:2890 __do_sys_clone kernel/fork.c:3033 [inline] __se_sys_clone kernel/fork.c:3017 [inline] __x64_sys_clone+0x193/0x200 kernel/fork.c:3017 x64_sys_call+0x990/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:57 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: 0033:0x7f7c75d9aeb9 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:00007f7c76cb5fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f7c76015fa0 RCX: 00007f7c75d9aeb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000022023400 RBP: 00007f7c75e08c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f7c76016038 R14: 00007f7c76015fa0 R15: 00007ffc303340d8 Allocated by task 2548: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 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+0x3a7/0x530 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x49c/0xd80 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4987 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107 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/0xf90 kernel/rcu/tree.c:2926 tnode_free net/ipv4/fib_trie.c:496 [inline] replace+0x1b7/0x4c0 net/ipv4/fib_trie.c:522 inflate net/ipv4/fib_trie.c:624 [inline] resize+0xb18/0x1c90 net/ipv4/fib_trie.c:869 trie_rebalance net/ipv4/fib_trie.c:1106 [inline] fib_insert_node net/ipv4/fib_trie.c:1150 [inline] fib_insert_alias+0xa1f/0x10b0 net/ipv4/fib_trie.c:1164 fib_table_insert+0x81d/0x1df0 net/ipv4/fib_trie.c:1359 fib_magic net/ipv4/fib_frontend.c:1118 [inline] fib_add_ifaddr+0x384/0xf10 net/ipv4/fib_frontend.c:1140 fib_inetaddr_event+0x15d/0x310 net/ipv4/fib_frontend.c:1454 notifier_call_chain kernel/notifier.c:87 [inline] blocking_notifier_call_chain+0xcb/0x150 kernel/notifier.c:382 __inet_insert_ifa+0x856/0xa30 net/ipv4/devinet.c:568 inet_rtm_newaddr+0x8c0/0x1650 net/ipv4/devinet.c:970 rtnetlink_rcv_msg+0xb3b/0xe00 net/core/rtnetlink.c:6150 netlink_rcv_skb+0x20f/0x460 net/netlink/af_netlink.c:2521 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6168 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x8ab/0xa30 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x8b9/0xbd0 net/netlink/af_netlink.c:1873 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] __sys_sendto+0x4ac/0x660 net/socket.c:2143 __do_sys_sendto net/socket.c:2155 [inline] __se_sys_sendto net/socket.c:2151 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2151 x64_sys_call+0x83/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 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 ffff8881321cf180 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff8881321cf180, ffff8881321cf1c0) The buggy address belongs to the physical page: page:ffffea0004c873c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8881321cf400 pfn:0x1321cf flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea0004cce948 ffffea000478d5c8 ffff888100042780 raw: ffff8881321cf400 0000000000200017 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 287, tgid 287 (syz-executor), ts 21475627410, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4554 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5868 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x203/0x2c0 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] tnode_alloc net/ipv4/fib_trie.c:332 [inline] tnode_new net/ipv4/fib_trie.c:385 [inline] fib_insert_node net/ipv4/fib_trie.c:1130 [inline] fib_insert_alias+0x381/0x10b0 net/ipv4/fib_trie.c:1164 fib_table_insert+0x81d/0x1df0 net/ipv4/fib_trie.c:1359 fib_magic net/ipv4/fib_frontend.c:1118 [inline] fib_add_ifaddr+0x937/0xf10 net/ipv4/fib_frontend.c:1155 fib_inetaddr_event+0x15d/0x310 net/ipv4/fib_frontend.c:1454 notifier_call_chain kernel/notifier.c:87 [inline] blocking_notifier_call_chain+0xcb/0x150 kernel/notifier.c:382 __inet_insert_ifa+0x856/0xa30 net/ipv4/devinet.c:568 page_owner free stack trace missing Memory state around the buggy address: ffff8881321cf080: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881321cf100: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8881321cf180: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881321cf200: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff8881321cf280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 6: 55 push %rbp 7: 48 89 e5 mov %rsp,%rbp a: be 02 00 00 00 mov $0x2,%esi f: e8 c2 12 00 00 call 0x12d6 14: 5d pop %rbp 15: c3 ret 16: 90 nop 17: 90 nop 18: 90 nop 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: b8 c9 ff ad 1b mov $0x1badffc9,%eax * 26: 55 push %rbp <-- trapping instruction 27: 48 89 e5 mov %rsp,%rbp 2a: 41 57 push %r15 2c: 41 56 push %r14 2e: 41 55 push %r13 30: 41 54 push %r12 32: 53 push %rbx 33: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp 37: 48 83 ec 60 sub $0x60,%rsp 3b: 49 rex.WB