================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:72 [inline] BUG: KASAN: null-ptr-deref in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: null-ptr-deref in page_ref_count include/linux/page_ref.h:67 [inline] BUG: KASAN: null-ptr-deref in folio_ref_count include/linux/page_ref.h:89 [inline] BUG: KASAN: null-ptr-deref in folio_get include/linux/mm.h:1167 [inline] BUG: KASAN: null-ptr-deref in hugetlb_fault+0x1423/0x23f0 mm/hugetlb.c:6112 Read of size 4 at addr 0000000000000034 by task syz-executor.2/5458 CPU: 0 PID: 5458 Comm: syz-executor.2 Not tainted 6.2.0-rc5-next-20230123-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 kasan_report+0xc0/0xf0 mm/kasan/report.c:517 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x141/0x190 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:72 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] page_ref_count include/linux/page_ref.h:67 [inline] folio_ref_count include/linux/page_ref.h:89 [inline] folio_get include/linux/mm.h:1167 [inline] hugetlb_fault+0x1423/0x23f0 mm/hugetlb.c:6112 handle_mm_fault+0x753/0x850 mm/memory.c:5196 do_user_addr_fault+0x475/0x1210 arch/x86/mm/fault.c:1407 handle_page_fault arch/x86/mm/fault.c:1498 [inline] exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1554 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:166 Code: d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 2c 66 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 0f 01 cb 83 fa 40 72 34 89 d1 a4 31 c0 0f 01 ca c3 89 ca eb 06 66 0f 1f 44 00 00 83 f8 12 74 RSP: 0018:ffffc90005577de0 EFLAGS: 00050202 RAX: 0000000000000001 RBX: 0000000000000078 RCX: 0000000000000078 RDX: 0000000000000078 RSI: ffffc90005577e48 RDI: 0000000020000300 RBP: 0000000020000300 R08: 0000000000000000 R09: ffffc90005577ebf R10: fffff52000aaefd7 R11: 0000000000094001 R12: 00007fffffffef88 R13: ffffc90005577e48 R14: ffff88802a29a010 R15: ffff88802a29a0d0 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 lib/usercopy.c:34 [inline] _copy_to_user+0x127/0x150 lib/usercopy.c:27 copy_to_user include/linux/uaccess.h:169 [inline] io_uring_create io_uring/io_uring.c:3772 [inline] io_uring_setup.cold+0x184b/0x1d99 io_uring/io_uring.c:3831 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd53848c0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd5391010e8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 00007fd5385ac120 RCX: 00007fd53848c0c9 RDX: 0000000020ee9000 RSI: 0000000020000300 RDI: 00000000000005d0 RBP: 0000000020000300 R08: 0000000020000040 R09: 0000000020000040 R10: 0000000020000240 R11: 0000000000000206 R12: 0000000020000040 R13: 0000000020ee9000 R14: 0000000020000240 R15: 0000000020ee8000 ================================================================== ---------------- Code disassembly (best guess): 0: d1 f3 shl %ebx 2: a4 movsb %ds:(%rsi),%es:(%rdi) 3: 31 c0 xor %eax,%eax 5: 0f 01 ca clac 8: c3 retq 9: 8d 0c ca lea (%rdx,%rcx,8),%ecx c: 89 ca mov %ecx,%edx e: eb 2c jmp 0x3c 10: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 17: 00 00 00 00 1b: 90 nop 1c: f3 0f 1e fa endbr64 20: 0f 01 cb stac 23: 83 fa 40 cmp $0x40,%edx 26: 72 34 jb 0x5c 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 retq 32: 89 ca mov %ecx,%edx 34: eb 06 jmp 0x3c 36: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 3c: 83 f8 12 cmp $0x12,%eax 3f: 74 .byte 0x74