================================================================== BUG: KASAN: stack-out-of-bounds in user_mode arch/x86/include/asm/ptrace.h:131 [inline] BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x10a0/0x1400 arch/x86/kernel/unwind_orc.c:410 Read of size 8 at addr ffff8880a98c70a0 by task syz-executor.3/18450 CPU: 0 PID: 18450 Comm: syz-executor.3 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 user_mode arch/x86/include/asm/ptrace.h:131 [inline] unwind_next_frame+0x10a0/0x1400 arch/x86/kernel/unwind_orc.c:410 perf_callchain_kernel+0x3fa/0x5c0 arch/x86/events/core.c:2346 get_perf_callchain+0x392/0x860 kernel/events/callchain.c:202 perf_callchain+0x165/0x1c0 kernel/events/core.c:6474 perf_prepare_sample+0x81e/0x1620 kernel/events/core.c:6501 __perf_event_output kernel/events/core.c:6616 [inline] perf_event_output_forward+0xf3/0x270 kernel/events/core.c:6634 __perf_event_overflow+0x13c/0x370 kernel/events/core.c:7907 perf_swevent_hrtimer+0x272/0x3e0 kernel/events/core.c:9261 __run_hrtimer kernel/time/hrtimer.c:1465 [inline] __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1527 hrtimer_interrupt+0x326/0x9e0 kernel/time/hrtimer.c:1585 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1071 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1096 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:784 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:806 [inline] RIP: 0010:lock_acquire+0x97/0x3c0 kernel/locking/lockdep.c:3903 Code: 82 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 eb 02 00 00 48 83 3d 50 2f a6 08 00 0f 84 75 02 00 00 9c <58> 0f 1f 44 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 44 24 08 48 RSP: 0018:ffff8880a98c6f48 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3050 RBX: ffff88809c284480 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88809c284d04 RBP: ffff888094ee5370 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000005 R11: 00000000bdde1f69 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001 dbAllocBits+0x3b7/0x520 fs/jfs/jfs_dmap.c:2284 retint_kernel+0x2d/0x2d RIP: 0000:unlock_page+0x13d/0x230 mm/filemap.c:1229 Code: 31 ff 83 e3 01 89 de e8 51 4f e6 ff 84 db 0f 84 a5 00 00 00 e8 14 4e e6 ff f0 80 65 00 fe 0f 98 c3 31 ff 89 de e8 33 4f e6 ff <84> db 75 0d 5b 5d 41 5c 41 5d 41 5e e9 f2 4d e6 ff e8 ed 4d e6 ff RSP: 8275473c:ffff88808a910428 EFLAGS: ffffea00024ff500 ORIG_RAX: ffffffffffffff13 RAX: ffff88809c284480 RBX: 0000000000000004 RCX: ffffffff8277f1a0 RDX: 0000000000000000 RSI: ffffffff8277f1ae RDI: 0000000000000007 RBP: ffffea00024ff500 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000007 R11: 00000000bdde1f69 R12: ffff88808a910428 R13: 0000000000000000 R14: 0000000000000000 R15: ffffea00024ff500 The buggy address belongs to the page: page:ffffea0002a631c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfff00000000000() raw: 00fff00000000000 0000000000000000 ffffffff00000101 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a98c6f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 ffff8880a98c7000: f1 f1 f1 00 00 00 f2 00 00 00 f2 f2 f2 00 00 00 >ffff8880a98c7080: 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 ^ ffff8880a98c7100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a98c7180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess), 3 bytes skipped: 0: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 7: fc ff df a: 48 c1 e8 03 shr $0x3,%rax e: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) 12: 0f 85 eb 02 00 00 jne 0x303 18: 48 83 3d 50 2f a6 08 cmpq $0x0,0x8a62f50(%rip) # 0x8a62f70 1f: 00 20: 0f 84 75 02 00 00 je 0x29b 26: 9c pushfq * 27: 58 pop %rax <-- trapping instruction 28: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 2d: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 34: fc ff df 37: 48 89 44 24 08 mov %rax,0x8(%rsp) 3c: 48 rex.W