================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 56 at addr ffff888111e27d10 by task syz.2.17/363 CPU: 1 PID: 363 Comm: syz.2.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: <#DB> __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_a82986b851e905af+0x21/0x33 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+0x3d0/0x5e0 kernel/events/core.c:10238 __perf_event_overflow+0x437/0x620 kernel/events/core.c:9448 perf_swevent_overflow kernel/events/core.c:9524 [inline] perf_swevent_event+0x2f7/0x530 kernel/events/core.c:-1 perf_bp_event+0x28c/0x330 kernel/events/core.c:10430 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x182/0x550 arch/x86/kernel/hw_breakpoint.c:586 notifier_call_chain kernel/notifier.c:87 [inline] atomic_notifier_call_chain kernel/notifier.c:225 [inline] notify_die+0x12a/0x1e0 kernel/notifier.c:593 notify_debug+0x24/0x30 arch/x86/kernel/traps.c:1018 exc_debug_kernel arch/x86/kernel/traps.c:1075 [inline] exc_debug+0xde/0x130 arch/x86/kernel/traps.c:1175 asm_exc_debug+0x1a/0x40 arch/x86/include/asm/idtentry.h:648 RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166 Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 a4 31 c0 0f 01 ca c3 89 ca eb 0a 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900009c7d28 EFLAGS: 00050202 RAX: ffffffff82688c01 RBX: 0000000000000050 RCX: 000000000000000f RDX: 0000000000000050 RSI: 0000200000000301 RDI: ffffc900009c7de1 RBP: ffffc900009c7d50 R08: ffffc900009c7def R09: 1ffff92000138fbd R10: dffffc0000000000 R11: fffff52000138fbe R12: 00007fffffffefb0 R13: 0000000000000050 R14: ffffc900009c7da0 R15: 00002000000002c0 copy_from_user include/linux/uaccess.h:161 [inline] copy_from_bpfptr_offset include/linux/bpfptr.h:53 [inline] copy_from_bpfptr include/linux/bpfptr.h:59 [inline] __sys_bpf+0x2a0/0x850 kernel/bpf/syscall.c:4976 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107 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 RIP: 0033:0x7feaf859c819 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:00007ffe5780b578 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007feaf8815fa0 RCX: 00007feaf859c819 RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000001c RBP: 00007feaf8632c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007feaf8815fac R14: 00007feaf8815fa0 R15: 00007feaf8815fa0 Allocated by task 363: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 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+0x3a7/0x530 kernel/bpf/stackmap.c:117 find_and_alloc_map kernel/bpf/syscall.c:133 [inline] map_create+0x49c/0xd80 kernel/bpf/syscall.c:1126 __sys_bpf+0x34e/0x850 kernel/bpf/syscall.c:4987 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5107 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 ffff888111e27d00 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff888111e27d00, ffff888111e27d40) The buggy address belongs to the physical page: page:ffffea00044789c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x111e27 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000001 ffff888100042780 raw: 0000000000000000 0000000080200020 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 104, tgid 104 (udevadm), ts 5539800387, free_ts 5539747534 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670 prep_new_page+0x1c/0x110 mm/page_alloc.c:2677 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5924 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc+0xa1/0x1e0 mm/slab_common.c:951 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] kobject_get_path+0xbf/0x200 lib/kobject.c:152 kobject_uevent_env+0x2a0/0x730 lib/kobject_uevent.c:544 kobject_synth_uevent+0x57e/0xbc0 lib/kobject_uevent.c:208 uevent_store+0x4b/0x70 drivers/base/core.c:2693 drv_attr_store+0x88/0xb0 drivers/base/bus.c:77 sysfs_kf_write+0x137/0x150 fs/sysfs/file.c:136 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1578 [inline] free_pcp_prepare mm/page_alloc.c:1652 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3618 free_unref_page+0x95/0x540 mm/page_alloc.c:3716 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6014 free_pages+0x82/0x90 mm/page_alloc.c:6025 selinux_genfs_get_sid+0x20b/0x250 security/selinux/hooks.c:1309 inode_doinit_with_dentry+0x87a/0xd80 security/selinux/hooks.c:1504 selinux_d_instantiate+0x27/0x40 security/selinux/hooks.c:6396 security_d_instantiate+0xb3/0x110 security/security.c:2096 d_splice_alias+0x6d/0x390 fs/dcache.c:3155 kernfs_iop_lookup+0x2c2/0x310 fs/kernfs/dir.c:1204 lookup_open fs/namei.c:3467 [inline] open_last_lookups fs/namei.c:3557 [inline] path_openat+0x1006/0x2f80 fs/namei.c:3787 do_filp_open+0x1f1/0x430 fs/namei.c:3817 do_sys_openat2+0x15e/0x810 fs/open.c:1343 do_sys_open fs/open.c:1359 [inline] __do_sys_openat fs/open.c:1375 [inline] __se_sys_openat fs/open.c:1370 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1370 x64_sys_call+0x783/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 Memory state around the buggy address: ffff888111e27c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888111e27c80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff888111e27d00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff888111e27d80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888111e27e00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess): 0: ff c9 dec %ecx 2: 75 f2 jne 0xfffffff6 4: 89 d1 mov %edx,%ecx 6: c1 e9 03 shr $0x3,%ecx 9: 83 e2 07 and $0x7,%edx c: f3 48 a5 rep movsq %ds:(%rsi),%es:(%rdi) f: 89 d1 mov %edx,%ecx 11: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) 13: 31 c0 xor %eax,%eax 15: 0f 01 ca clac 18: c3 ret 19: 8d 0c ca lea (%rdx,%rcx,8),%ecx 1c: 89 ca mov %ecx,%edx 1e: eb 20 jmp 0x40 20: 0f 01 cb stac 23: 83 fa 40 cmp $0x40,%edx 26: 72 38 jb 0x60 28: 89 d1 mov %edx,%ecx * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 89 ca mov %ecx,%edx 34: eb 0a jmp 0x40 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop