================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c7/0x900 kernel/bpf/stackmap.c:271 Write of size 48 at addr ffff88802e215f10 by task syz.0.1845/11234 CPU: 0 PID: 11234 Comm: syz.0.1845 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0x6c7/0x900 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_1649ecc1a5870555+0x29/0x39 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:10576 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712 perf_swevent_overflow kernel/events/core.c:9795 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9846 do_perf_sw_event kernel/events/core.c:9959 [inline] ___perf_sw_event+0x4ab/0x730 kernel/events/core.c:9990 __perf_sw_event+0x139/0x270 kernel/events/core.c:10002 perf_sw_event include/linux/perf_event.h:1442 [inline] do_user_addr_fault+0x1242/0x12d0 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:__put_user_4+0x11/0x20 arch/x86/lib/putuser.S:89 Code: 01 ca c3 90 90 90 90 90 90 f3 0f 1e fa 0f 01 cb 66 89 01 31 c9 0f 01 ca c3 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <89> 01 31 c9 0f 01 ca c3 90 90 90 90 90 90 90 f3 0f 1e fa 0f 01 cb RSP: 0018:ffffc90004cdfc58 EFLAGS: 00050246 RAX: 000000000000053e RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8acadce0 RDI: ffffffff8b1cfa20 RBP: ffffc90004cdfd90 R08: ffffffff8e8c6b2f R09: 1ffffffff1d18d65 R10: dffffc0000000000 R11: fffffbfff1d18d66 R12: 1ffff9200099bf94 R13: dffffc0000000000 R14: 00000000ae12e400 R15: 000000000000053e kernel_clone+0x36c/0x8a0 kernel/fork.c:2933 __do_sys_clone kernel/fork.c:3060 [inline] __se_sys_clone kernel/fork.c:3044 [inline] __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3044 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe83bf9de59 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:00007fe83cd89fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fe83c225fa0 RCX: 00007fe83bf9de59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000ae12e400 RBP: 00007fe83c033e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fe83c226038 R14: 00007fe83c225fa0 R15: 00007fffd6c18708 Allocated by task 11234: 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+0xb6/0x240 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+0x32b/0x4b0 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+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88802e215f00 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of allocated 40-byte region [ffff88802e215f00, ffff88802e215f28) The buggy address belongs to the physical page: page:ffffea0000b88540 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802e215480 pfn:0x2e215 memcg:ffff8880245e1401 ksm flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c4da00 ffffea00009a3bc0 0000000000000007 raw: ffff88802e215480 000000008020001f 00000001ffffffff ffff8880245e1401 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 5777, tgid 5777 (syz-executor), ts 294012308791, free_ts 294011892385 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/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+0x11f/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+0x747/0xa20 fs/file.c:346 copy_files+0xaf/0x110 kernel/fork.c:1796 copy_process+0x15d1/0x3df0 kernel/fork.c:2496 kernel_clone+0x24b/0x8a0 kernel/fork.c:2917 __do_sys_clone kernel/fork.c:3060 [inline] __se_sys_clone kernel/fork.c:3044 [inline] __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3044 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 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:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 vfree+0x1a7/0x340 mm/vmalloc.c:2868 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:880 [inline] get_entries net/ipv6/netfilter/ip6_tables.c:1037 [inline] do_ip6t_get_ctl+0xf01/0x1220 net/ipv6/netfilter/ip6_tables.c:1674 nf_getsockopt+0x262/0x280 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x233/0x2e0 net/ipv6/ipv6_sockglue.c:1499 do_sock_getsockopt+0x379/0x450 net/socket.c:2384 __sys_getsockopt net/socket.c:2413 [inline] __do_sys_getsockopt net/socket.c:2423 [inline] __se_sys_getsockopt net/socket.c:2420 [inline] __x64_sys_getsockopt+0x1d6/0x280 net/socket.c:2420 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88802e215e00: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ffff88802e215e80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88802e215f00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802e215f80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88802e216000: fb fb fb fb fb fc fc fb fb fb fb fb fc fc fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 01 ca add %ecx,%edx 2: c3 ret 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: f3 0f 1e fa endbr64 d: 0f 01 cb stac 10: 66 89 01 mov %ax,(%rcx) 13: 31 c9 xor %ecx,%ecx 15: 0f 01 ca clac 18: c3 ret 19: f3 0f 1e fa endbr64 1d: 48 89 cb mov %rcx,%rbx 20: 48 c1 fb 3f sar $0x3f,%rbx 24: 48 09 d9 or %rbx,%rcx 27: 0f 01 cb stac * 2a: 89 01 mov %eax,(%rcx) <-- trapping instruction 2c: 31 c9 xor %ecx,%ecx 2e: 0f 01 ca clac 31: c3 ret 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: f3 0f 1e fa endbr64 3d: 0f 01 cb stac