================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 64 at addr ffff88811c3b5090 by task syz.3.1594/6279 CPU: 1 PID: 6279 Comm: syz.3.1594 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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_6611c23d801ea08d+0x21/0x36 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+0x3c7/0x5e0 kernel/events/core.c:10273 __perf_event_overflow+0x458/0x640 kernel/events/core.c:9448 perf_event_overflow kernel/events/core.c:9469 [inline] perf_swevent_hrtimer+0x4b4/0x540 kernel/events/core.c:10919 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x398/0x8a0 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x3ad/0x8c0 kernel/time/hrtimer.c:1815 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:__sanitizer_cov_trace_switch+0x5a/0xe0 kernel/kcov.c:348 Code: 0f 84 a8 00 00 00 55 48 89 e5 41 57 41 56 41 54 53 48 8d 4c 09 01 48 8b 55 08 65 4c 8b 05 fe fd 90 7e 45 31 c9 eb 08 49 ff c1 <4c> 39 c8 74 77 4e 8b 54 ce 10 65 44 8b 1d ec fd 90 7e 41 81 e3 00 RSP: 0018:ffffc90000bb7cb0 EFLAGS: 00000203 RAX: 000000000000000d RBX: 0000000000000000 RCX: 0000000000000005 RDX: ffffffff81673d42 RSI: ffffffff871ce9e0 RDI: 0000000000000001 RBP: ffffc90000bb7cd0 R08: ffff8881159ea880 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000001 R14: 1ffff92000176fa4 R15: 0000000000000001 do_futex+0xe2/0x430 kernel/futex/syscalls.c:131 __do_sys_futex kernel/futex/syscalls.c:213 [inline] __se_sys_futex+0x136/0x310 kernel/futex/syscalls.c:194 __x64_sys_futex+0xe5/0x100 kernel/futex/syscalls.c:194 x64_sys_call+0x7ec/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:203 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: 0033:0x7f696fb9e159 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:00007f69709dd0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f696fe25fa8 RCX: 00007f696fb9e159 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f696fe25fac RBP: 00007f696fe25fa0 R08: 003116aa2a6c1c84 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f696fe26038 R14: 00007ffce5607ef0 R15: 00007ffce5607fd8 Allocated by task 6279: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/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+0x398/0x520 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x467/0xcf0 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4988 __do_sys_bpf kernel/bpf/syscall.c:5110 [inline] __se_sys_bpf kernel/bpf/syscall.c:5108 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5108 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 The buggy address belongs to the object at ffff88811c3b5080 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 16 bytes inside of 32-byte region [ffff88811c3b5080, ffff88811c3b50a0) The buggy address belongs to the physical page: page:ffffea000470ed40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11c3b5 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 dead000000000100 dead000000000122 ffff888100042600 raw: 0000000000000000 0000000080400040 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 113, tgid 113 (udevd), ts 5811103099, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3e0 mm/slub.c:2020 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node_track_caller+0xa1/0x1e0 mm/slab_common.c:958 memdup_user+0x2a/0xc0 mm/util.c:179 proc_pid_attr_write+0x1d7/0x2e0 fs/proc/base.c:2853 vfs_write+0x3fb/0xd00 fs/read_write.c:582 ksys_write+0x14a/0x260 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 page_owner free stack trace missing Memory state around the buggy address: ffff88811c3b4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88811c3b5000: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff88811c3b5080: 00 00 00 fc fc fc fc fc 00 00 01 fc fc fc fc fc ^ ffff88811c3b5100: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff88811c3b5180: fb fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 a8 00 00 00 je 0xae 6: 55 push %rbp 7: 48 89 e5 mov %rsp,%rbp a: 41 57 push %r15 c: 41 56 push %r14 e: 41 54 push %r12 10: 53 push %rbx 11: 48 8d 4c 09 01 lea 0x1(%rcx,%rcx,1),%rcx 16: 48 8b 55 08 mov 0x8(%rbp),%rdx 1a: 65 4c 8b 05 fe fd 90 mov %gs:0x7e90fdfe(%rip),%r8 # 0x7e90fe20 21: 7e 22: 45 31 c9 xor %r9d,%r9d 25: eb 08 jmp 0x2f 27: 49 ff c1 inc %r9 * 2a: 4c 39 c8 cmp %r9,%rax <-- trapping instruction 2d: 74 77 je 0xa6 2f: 4e 8b 54 ce 10 mov 0x10(%rsi,%r9,8),%r10 34: 65 44 8b 1d ec fd 90 mov %gs:0x7e90fdec(%rip),%r11d # 0x7e90fe28 3b: 7e 3c: 41 rex.B 3d: 81 .byte 0x81 3e: e3 00 jrcxz 0x40