================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 48 at addr ffff88802cc35f60 by task syz.0.26/4433 CPU: 0 PID: 4433 Comm: syz.0.26 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x3c/0x60 mm/kasan/shadow.c:66 __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 ____bpf_get_stackid_pe kernel/bpf/stackmap.c:377 [inline] bpf_get_stackid_pe+0x2ec/0x400 kernel/bpf/stackmap.c:334 bpf_prog_644fb7c94e15512a+0x2b/0x40 bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x522/0x7c0 kernel/events/core.c:10321 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 perf_event_overflow kernel/events/core.c:9517 [inline] perf_swevent_hrtimer+0x472/0x630 kernel/events/core.c:10967 __run_hrtimer kernel/time/hrtimer.c:1747 [inline] __hrtimer_run_queues+0x50b/0xd50 kernel/time/hrtimer.c:1811 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0033:0x7f5cc0a65715 Code: e8 60 52 ff ff 48 8b 05 69 00 ee 00 83 05 52 00 ee 00 01 be 08 00 00 00 48 89 ef 48 8d 50 ff 48 89 15 4f 00 ee 00 44 88 78 ff <44> 8b 3d 34 00 ee 00 e8 2f 52 ff ff 48 8b 05 40 00 ee 00 44 89 38 RSP: 002b:00007ffe1e883d00 EFLAGS: 00000202 RAX: 0000001b2e263fbc RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000001b2e263fbb RSI: 0000000000000008 RDI: 00007f5cc1945720 RBP: 00007f5cc1945720 R08: 0000000000000000 R09: 00007f5cc0e16038 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000003 Allocated by task 4433: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node+0xb0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline] bpf_map_area_alloc+0x47/0xe0 kernel/bpf/syscall.c:341 prealloc_elems_and_freelist+0x86/0x1c0 kernel/bpf/stackmap.c:51 stack_map_alloc+0x390/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x534/0x1000 kernel/bpf/syscall.c:1149 __sys_bpf+0x38b/0x780 kernel/bpf/syscall.c:5013 __do_sys_bpf kernel/bpf/syscall.c:5135 [inline] __se_sys_bpf kernel/bpf/syscall.c:5133 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5133 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 ffff88802cc35f00 which belongs to the cache kmalloc-cg-128 of size 128 The buggy address is located 96 bytes inside of 128-byte region [ffff88802cc35f00, ffff88802cc35f80) The buggy address belongs to the physical page: page:ffffea0000b30d40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2cc35 memcg:ffff888072e8fe01 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888017442a00 raw: 0000000000000000 0000000080100010 00000001ffffffff ffff888072e8fe01 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 4376, tgid 4376 (syz-executor), ts 86903325614, free_ts 86903095769 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x6c/0x180 mm/util.c:581 kvmalloc include/linux/slab.h:716 [inline] kvzalloc include/linux/slab.h:724 [inline] allocate_hook_entries_size net/netfilter/core.c:61 [inline] nf_hook_entries_grow+0x309/0x730 net/netfilter/core.c:128 __nf_register_net_hook+0x2c9/0x910 net/netfilter/core.c:423 nf_register_net_hook+0xae/0x190 net/netfilter/core.c:566 nf_register_net_hooks+0x40/0x1a0 net/netfilter/core.c:582 nf_nat_register_fn+0x3cb/0x580 net/netfilter/nf_nat_core.c:1039 ipt_nat_register_lookups net/ipv4/netfilter/iptable_nat.c:77 [inline] iptable_nat_table_init+0xd0/0x2d0 net/ipv4/netfilter/iptable_nat.c:121 xt_find_table_lock+0x220/0x360 net/netfilter/x_tables.c:1282 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 __vunmap+0x856/0xa00 mm/vmalloc.c:2726 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:868 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1024 [inline] do_ipt_get_ctl+0xead/0x1190 net/ipv4/netfilter/ip_tables.c:1670 nf_getsockopt+0x25e/0x280 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x19b/0x230 net/ipv4/ip_sockglue.c:1826 __sys_getsockopt+0x1b0/0x230 net/socket.c:2331 __do_sys_getsockopt net/socket.c:2346 [inline] __se_sys_getsockopt net/socket.c:2343 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2343 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 Memory state around the buggy address: ffff88802cc35e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802cc35e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802cc35f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc ^ ffff88802cc35f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802cc36000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================