================================================================== 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.3/22694 CPU: 0 PID: 22694 Comm: syz-executor.3 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:__put_user_4+0x16/0x20 arch/x86/lib/putuser.S:95 Code: 89 01 31 c9 0f 01 ca c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 bb fd ef ff ff ff 7f 00 00 48 39 d9 73 70 0f 01 cb <89> 01 31 c9 0f 01 ca c3 66 90 f3 0f 1e fa f3 0f 1e fa 0f 01 cb 89 RSP: 0018:ffffc90015ce7e40 EFLAGS: 00050293 RAX: 0000000000000004 RBX: 00007fffffffeffd RCX: 0000000020000080 RDX: 0000000000040000 RSI: ffffffff87c1513f RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000005 R14: 0000000000000000 R15: dffffc0000000000 __sys_socketpair+0x10b/0x570 net/socket.c:1710 __do_sys_socketpair net/socket.c:1776 [inline] __se_sys_socketpair net/socket.c:1773 [inline] __x64_sys_socketpair+0x97/0x100 net/socket.c:1773 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: 0033:0x7f12a9c8c0c9 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:00007f12aaaa8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000035 RAX: ffffffffffffffda RBX: 00007f12a9dabf80 RCX: 00007f12a9c8c0c9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 00007f12a9ce7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020000080 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd5f7c580f R14: 00007f12aaaa8300 R15: 0000000000022000 ================================================================== ---------------- Code disassembly (best guess): 0: 89 01 mov %eax,(%rcx) 2: 31 c9 xor %ecx,%ecx 4: 0f 01 ca clac 7: c3 retq 8: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) f: 00 00 00 00 13: 90 nop 14: f3 0f 1e fa endbr64 18: 48 bb fd ef ff ff ff movabs $0x7fffffffeffd,%rbx 1f: 7f 00 00 22: 48 39 d9 cmp %rbx,%rcx 25: 73 70 jae 0x97 27: 0f 01 cb stac * 2a: 89 01 mov %eax,(%rcx) <-- trapping instruction 2c: 31 c9 xor %ecx,%ecx 2e: 0f 01 ca clac 31: c3 retq 32: 66 90 xchg %ax,%ax 34: f3 0f 1e fa endbr64 38: f3 0f 1e fa endbr64 3c: 0f 01 cb stac 3f: 89 .byte 0x89