================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x677/0xcf0 kernel/bpf/stackmap.c:265 Write of size 8 at addr ffff888056850a48 by task syz.1.2860/17582 CPU: 1 UID: 0 PID: 17582 Comm: syz.1.2860 Not tainted 6.17.0-rc1-syzkaller-ge4414b01c1cd #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __bpf_get_stackid+0x677/0xcf0 kernel/bpf/stackmap.c:265 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1810 [inline] bpf_get_stackid_raw_tp+0x196/0x210 kernel/trace/bpf_trace.c:1799 bpf_prog_b724608cae728045+0x27/0x2f bpf_dispatcher_nop_func include/linux/bpf.h:1332 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline] bpf_trace_run2+0x284/0x4b0 kernel/trace/bpf_trace.c:2298 __do_trace_kfree include/trace/events/kmem.h:94 [inline] trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x3a0/0x440 mm/slub.c:4866 sk_prot_free net/core/sock.c:2278 [inline] __sk_destruct+0x4e1/0x660 net/core/sock.c:2373 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xca8/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 ab 86 4b f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 f3 2d 14 f6 65 8b 05 6c 71 24 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90010fb6dc0 EFLAGS: 00000206 RAX: 53f60afe55939500 RBX: 0000000000000246 RCX: 53f60afe55939500 RDX: 0000000000000000 RSI: ffffffff8d9b6d6c RDI: 0000000000000001 RBP: ffffc90010fb6e50 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6 R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: dffffc0000000000 R13: ffffffff8e13f200 R14: ffffffff8e13f200 R15: 1ffff920021f6db8 rcu_preempt_deferred_qs_irqrestore+0x89c/0xce0 kernel/rcu/tree_plugin.h:-1 rcu_read_unlock_special+0x475/0x5e0 kernel/rcu/tree_plugin.h:775 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438 page_table_check_alloc include/linux/page_table_check.h:35 [inline] post_alloc_hook+0x253/0x2a0 mm/page_alloc.c:1852 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 ___kmalloc_large_node+0x5f/0x1b0 mm/slub.c:4306 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4337 __do_kmalloc_node mm/slub.c:4353 [inline] __kvmalloc_node_noprof+0x6d/0x5f0 mm/slub.c:5052 bpf_check+0xf9/0x1d2d0 kernel/bpf/verifier.c:24585 bpf_prog_load+0x1318/0x1930 kernel/bpf/syscall.c:2979 __sys_bpf+0x528/0x870 kernel/bpf/syscall.c:6029 __do_sys_bpf kernel/bpf/syscall.c:6139 [inline] __se_sys_bpf kernel/bpf/syscall.c:6137 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f252098ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f25217a3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f2520bb5fa0 RCX: 00007f252098ebe9 RDX: 0000000000000048 RSI: 00002000000017c0 RDI: 0000000000000005 RBP: 00007f2520a11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2520bb6038 R14: 00007f2520bb5fa0 R15: 00007ffc41ea58c8 Allocated by task 17582: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kmalloc_node_noprof+0x276/0x4e0 mm/slub.c:4371 kmalloc_node_noprof include/linux/slab.h:932 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:393 [inline] bpf_map_area_alloc+0x64/0x180 kernel/bpf/syscall.c:406 prealloc_elems_and_freelist+0x86/0x1d0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x33f/0x4c0 kernel/bpf/stackmap.c:114 map_create+0xaa0/0x14d0 kernel/bpf/syscall.c:1480 __sys_bpf+0x60f/0x870 kernel/bpf/syscall.c:6011 __do_sys_bpf kernel/bpf/syscall.c:6139 [inline] __se_sys_bpf kernel/bpf/syscall.c:6137 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6137 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888056850800 which belongs to the cache kmalloc-cg-1k of size 1024 The buggy address is located 8 bytes to the right of allocated 576-byte region [ffff888056850800, ffff888056850a40) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56850 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802b1a5201 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a44b280 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080100010 00000000f5000000 ffff88802b1a5201 head: 00fff00000000040 ffff88801a44b280 dead000000000100 dead000000000122 head: 0000000000000000 0000000080100010 00000000f5000000 ffff88802b1a5201 head: 00fff00000000003 ffffea00015a1401 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 5874, tgid 5874 (syz-executor), ts 99559052927, free_ts 31514967989 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] __register_sysctl_table+0x72/0x1340 fs/proc/proc_sysctl.c:1379 neigh_sysctl_register+0x9a2/0xa80 net/core/neighbour.c:3887 addrconf_sysctl_register+0xb3/0x1c0 net/ipv6/addrconf.c:7365 ipv6_add_dev+0xd46/0x1370 net/ipv6/addrconf.c:460 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11227 veth_newlink+0x5cc/0xa50 drivers/net/veth.c:1884 rtnl_newlink_create+0x30d/0xb00 net/core/rtnetlink.c:3825 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 __free_pages mm/page_alloc.c:5260 [inline] free_contig_range+0x1bd/0x4a0 mm/page_alloc.c:7091 destroy_args+0x64/0x4a0 mm/debug_vm_pgtable.c:958 debug_vm_pgtable+0x39f/0x3b0 mm/debug_vm_pgtable.c:1340 do_one_initcall+0x233/0x820 init/main.c:1269 do_initcall_level+0x104/0x190 init/main.c:1331 do_initcalls+0x59/0xa0 init/main.c:1347 kernel_init_freeable+0x334/0x4b0 init/main.c:1579 kernel_init+0x1d/0x1d0 init/main.c:1469 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888056850900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888056850980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888056850a00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ^ ffff888056850a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888056850b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 ab 86 4b f6 call 0xf64b86b2 7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) e: 00 00 10: 9c pushf 11: 8f 44 24 20 pop 0x20(%rsp) 15: f6 44 24 21 02 testb $0x2,0x21(%rsp) 1a: 75 4f jne 0x6b 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 f3 2d 14 f6 call 0xf6142e22 <-- trapping instruction 2f: 65 8b 05 6c 71 24 07 mov %gs:0x724716c(%rip),%eax # 0x72471a2 36: 85 c0 test %eax,%eax 38: 74 40 je 0x7a 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss