================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6c9/0x920 kernel/bpf/stackmap.c:274 Write of size 88 at addr ffff88806651dd90 by task syz.4.6732/30040 CPU: 0 PID: 30040 Comm: syz.4.6732 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:365 [inline] bpf_get_stackid_pe+0x33f/0x400 kernel/bpf/stackmap.c:334 bpf_prog_6611c23d801ea08d+0x21/0x36 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_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 do_perf_sw_event kernel/events/core.c:9743 [inline] ___perf_sw_event+0x49e/0x6e0 kernel/events/core.c:9774 __perf_sw_event+0x135/0x260 kernel/events/core.c:9786 perf_sw_event include/linux/perf_event.h:1254 [inline] do_user_addr_fault+0xaea/0xb10 arch/x86/mm/fault.c:1284 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:copy_user_short_string+0xd/0x40 arch/x86/lib/copy_user_64.S:233 Code: 74 0a 89 d1 f3 a4 89 c8 0f 01 ca c3 89 d0 0f 01 ca c3 01 ca eb e7 90 90 90 90 90 90 90 89 d1 83 e2 07 c1 e9 03 74 12 4c 8b 06 <4c> 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10 89 d1 8a RSP: 0018:ffffc900052772a8 EFLAGS: 00050202 RAX: ffffffff84115c01 RBX: 000000000000000b RCX: 0000000000000001 RDX: 0000000000000003 RSI: ffff88807b2f866c RDI: 000020000000cf3d RBP: 0000000000000000 R08: 40203023636e7566 R09: 1ffff1100f65f0ce R10: dffffc0000000000 R11: ffffed100f65f0cf R12: 00007fffffffeff5 R13: 000000000000000b R14: 000020000000cf3d R15: ffff88807b2f866c copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] _copy_to_user+0xea/0x130 lib/usercopy.c:41 copy_to_user include/linux/uaccess.h:169 [inline] bpf_verifier_vlog+0x172/0x390 kernel/bpf/log.c:34 verbose+0x1f2/0x2b0 kernel/bpf/verifier.c:303 add_subprog_and_kfunc kernel/bpf/verifier.c:2165 [inline] bpf_check+0x301b/0x10db0 kernel/bpf/verifier.c:15552 bpf_prog_load+0x101a/0x1560 kernel/bpf/syscall.c:2651 __sys_bpf+0x5b8/0x780 kernel/bpf/syscall.c:5031 __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 RIP: 0033:0x7fada8f9ce59 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:00007fada9e68028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fada9215fa0 RCX: 00007fada8f9ce59 RDX: 0000000000000048 RSI: 000020000000e000 RDI: 0000000000000005 RBP: 00007fada9032d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fada9216038 R14: 00007fada9215fa0 R15: 00007ffc25db9008 Allocated by task 30040: 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 ffff88806651dd80 which belongs to the cache kmalloc-cg-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88806651dd80, ffff88806651ddc0) The buggy address belongs to the physical page: page:ffffea0001994740 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88806651de80 pfn:0x6651d memcg:ffff88807f5cb801 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000001 ffff888017442780 raw: ffff88806651de80 000000008020001e 00000001ffffffff ffff88807f5cb801 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 27927, tgid 27918 (syz.4.6152), ts 1228131093632, free_ts 1228095876824 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 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] alloc_fdtable+0xca/0x2c0 fs/file.c:147 dup_fd+0x782/0xa50 fs/file.c:346 copy_files+0x72/0xe0 kernel/fork.c:1641 copy_process+0x1835/0x4030 kernel/fork.c:2344 kernel_clone+0x24b/0x900 kernel/fork.c:2762 __do_sys_clone kernel/fork.c:2903 [inline] __se_sys_clone kernel/fork.c:2887 [inline] __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2887 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 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 tlb_batch_list_free mm/mmu_gather.c:76 [inline] tlb_finish_mmu+0x140/0x220 mm/mmu_gather.c:397 exit_mmap+0x384/0x960 mm/mmap.c:3262 __mmput+0x118/0x3c0 kernel/fork.c:1205 exit_mm+0x25a/0x360 kernel/exit.c:566 do_exit+0x905/0x2480 kernel/exit.c:868 do_group_exit+0x217/0x2d0 kernel/exit.c:1023 get_signal+0x1272/0x1350 kernel/signal.c:2871 arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88806651dc80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88806651dd00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88806651dd80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88806651de00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88806651de80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: 74 0a je 0xc 2: 89 d1 mov %edx,%ecx 4: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) 6: 89 c8 mov %ecx,%eax 8: 0f 01 ca clac b: c3 ret c: 89 d0 mov %edx,%eax e: 0f 01 ca clac 11: c3 ret 12: 01 ca add %ecx,%edx 14: eb e7 jmp 0xfffffffd 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 89 d1 mov %edx,%ecx 1f: 83 e2 07 and $0x7,%edx 22: c1 e9 03 shr $0x3,%ecx 25: 74 12 je 0x39 27: 4c 8b 06 mov (%rsi),%r8 * 2a: 4c 89 07 mov %r8,(%rdi) <-- trapping instruction 2d: 48 8d 76 08 lea 0x8(%rsi),%rsi 31: 48 8d 7f 08 lea 0x8(%rdi),%rdi 35: ff c9 dec %ecx 37: 75 ee jne 0x27 39: 21 d2 and %edx,%edx 3b: 74 10 je 0x4d 3d: 89 d1 mov %edx,%ecx 3f: 8a .byte 0x8a