================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 56 at addr ffff8881091fab10 by task syz.0.395/2185 CPU: 1 PID: 2185 Comm: syz.0.395 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 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_02c92f715e75ceb8+0x28/0x3d bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline] __bpf_prog_run include/linux/filter.h:596 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x521/0x5e0 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:put_ctx+0x1/0x190 kernel/events/core.c:1212 Code: a2 da ff be 02 00 00 00 eb 0a e8 fa a1 da ff be 01 00 00 00 48 89 df e8 8d 65 d2 00 eb d9 66 2e 0f 1f 84 00 00 00 00 00 90 55 <48> 89 e5 41 57 41 56 41 54 53 48 89 fb e8 cd a1 da ff 4c 8d b3 c0 RSP: 0018:ffffc90001cdfbd0 EFLAGS: 00000246 RAX: 0a92881ee2ea7700 RBX: ffff888132871c00 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888132871c00 RBP: ffffc90001cdfe80 R08: ffffc90001cdfb67 R09: 1ffff9200039bf6c R10: dffffc0000000000 R11: fffff5200039bf6d R12: 0000000040042408 R13: dffffc0000000000 R14: fffff5200039bf8c R15: 0000000000000000 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 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: 0033:0x7febfe19e199 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:00007febff159028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007febfe425fa0 RCX: 00007febfe19e199 RDX: 0000000000000005 RSI: 0000000040042408 RDI: 0000000000000006 RBP: 00007febfe2358e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007febfe426038 R14: 00007febfe425fa0 R15: 00007ffd2c7dc128 Allocated by task 2185: 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 ffff8881091fab00 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff8881091fab00, ffff8881091fab40) The buggy address belongs to the physical page: page:ffffea0004247e80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1091fa flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000001 ffff888100042780 raw: 0000000000000000 0000000000200020 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 746, tgid 725 (syz.4.99), ts 33121367688, free_ts 33093224321 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 __do_krealloc mm/slab_common.c:1341 [inline] krealloc+0x6f/0x110 mm/slab_common.c:1374 push_jmp_history kernel/bpf/verifier.c:2462 [inline] is_state_visited kernel/bpf/verifier.c:12321 [inline] do_check+0x2dcd/0xf140 kernel/bpf/verifier.c:12461 do_check_common+0x11c3/0x1970 kernel/bpf/verifier.c:14940 do_check_main kernel/bpf/verifier.c:15003 [inline] bpf_check+0xa04e/0x10e90 kernel/bpf/verifier.c:15580 bpf_prog_load+0x10f4/0x1670 kernel/bpf/syscall.c:2624 __sys_bpf+0x57b/0x850 kernel/bpf/syscall.c:5006 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1581 [inline] free_pcp_prepare mm/page_alloc.c:1655 [inline] free_unref_page_prepare+0x81b/0x820 mm/page_alloc.c:3622 free_unref_page+0x93/0x530 mm/page_alloc.c:3720 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6021 free_pages+0x82/0x90 mm/page_alloc.c:6032 kasan_depopulate_vmalloc_pte+0x6b/0x90 mm/kasan/shadow.c:375 apply_to_pte_range mm/memory.c:2690 [inline] apply_to_pmd_range mm/memory.c:2734 [inline] apply_to_pud_range mm/memory.c:2770 [inline] apply_to_p4d_range mm/memory.c:2806 [inline] __apply_to_page_range+0x8db/0xc80 mm/memory.c:2842 apply_to_existing_page_range+0x38/0x50 mm/memory.c:2875 kasan_release_vmalloc+0x97/0xb0 mm/kasan/shadow.c:492 __purge_vmap_area_lazy+0xf09/0x1870 mm/vmalloc.c:1791 drain_vmap_area_work+0x3e/0xd0 mm/vmalloc.c:1820 process_one_work+0x717/0xc30 kernel/workqueue.c:2302 worker_thread+0xa4d/0x11d0 kernel/workqueue.c:2449 kthread+0x281/0x320 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff8881091faa00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881091faa80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8881091fab00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881091fab80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881091fac00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: a2 da ff be 02 00 00 movabs %al,0xeb00000002beffda 7: 00 eb 9: 0a e8 or %al,%ch b: fa cli c: a1 da ff be 01 00 00 movabs 0x4800000001beffda,%eax 13: 00 48 15: 89 df mov %ebx,%edi 17: e8 8d 65 d2 00 call 0xd265a9 1c: eb d9 jmp 0xfffffff7 1e: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 25: 00 00 00 28: 90 nop 29: 55 push %rbp * 2a: 48 89 e5 mov %rsp,%rbp <-- trapping instruction 2d: 41 57 push %r15 2f: 41 56 push %r14 31: 41 54 push %r12 33: 53 push %rbx 34: 48 89 fb mov %rdi,%rbx 37: e8 cd a1 da ff call 0xffdaa209 3c: 4c rex.WR 3d: 8d .byte 0x8d 3e: b3 c0 mov $0xc0,%bl