================================================================== BUG: KASAN: slab-out-of-bounds in __bpf_get_stackid+0x6fa/0x960 kernel/bpf/stackmap.c:274 Write of size 72 at addr ffff88811b0ae210 by task syz.0.501/2365 CPU: 0 PID: 2365 Comm: syz.0.501 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_9f7ee0cc743aa62b+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_swevent_overflow+0x1ae/0x240 kernel/events/core.c:9531 perf_swevent_event+0x3a9/0x440 kernel/events/core.c:-1 do_perf_sw_event kernel/events/core.c:9695 [inline] ___perf_sw_event+0x3bf/0x500 kernel/events/core.c:9726 __perf_sw_event+0x134/0x270 kernel/events/core.c:9738 perf_sw_event include/linux/perf_event.h:1250 [inline] do_user_addr_fault+0xfe9/0x1030 arch/x86/mm/fault.c:1285 handle_page_fault arch/x86/mm/fault.c:1464 [inline] exc_page_fault+0x51/0xb0 arch/x86/mm/fault.c:1517 asm_exc_page_fault+0x27/0x30 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:ffffc900011c7cc8 EFLAGS: 00050206 RAX: ffffffff82692e01 RBX: 0000000000000028 RCX: 0000000000000005 RDX: 0000000000000000 RSI: ffffc900011c7d70 RDI: 00002000000000c0 RBP: ffffc900011c7cf0 R08: 656c6c616b7a7973 R09: 1ffff92000238fb2 R10: dffffc0000000000 R11: fffff52000238fb3 R12: 00007fffffffefd8 R13: 0000000000000000 R14: 00002000000000c0 R15: ffffc900011c7d70 copy_to_user include/linux/uaccess.h:169 [inline] __tun_chr_ioctl+0xa05/0x1ef0 drivers/net/tun.c:3122 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3404 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: 0033:0x7f6d3659e159 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:00007f6d37406028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6d36825fa0 RCX: 00007f6d3659e159 RDX: 00002000000000c0 RSI: 00000000400454ca RDI: 0000000000000004 RBP: 00007f6d3663506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6d36826038 R14: 00007f6d36825fa0 R15: 00007fff87ee7618 Allocated by task 2372: 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 ffff88811b0ae200 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 16 bytes inside of 64-byte region [ffff88811b0ae200, ffff88811b0ae240) The buggy address belongs to the physical page: page:ffffea00046c2b80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11b0ae flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 ffffea00046c7600 dead000000000002 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 115, tgid 115 (udevd), ts 4578438870, 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+0xa2/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x28a/0x460 mm/util.c:592 kvmalloc include/linux/slab.h:716 [inline] simple_xattr_alloc+0x43/0xa0 fs/xattr.c:1008 shmem_initxattrs+0x8d/0x1e0 mm/shmem.c:3294 security_inode_init_security+0x295/0x3c0 security/security.c:1134 shmem_symlink+0xd0/0x4c0 mm/shmem.c:3166 vfs_symlink+0x261/0x3f0 fs/namei.c:4478 page_owner free stack trace missing Memory state around the buggy address: ffff88811b0ae100: 00 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc ffff88811b0ae180: 00 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc >ffff88811b0ae200: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ^ ffff88811b0ae280: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88811b0ae300: 00 00 00 00 00 00 00 02 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