================================================================== 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 ffff888091d57dc0 by task syz-executor.3/15690 CPU: 0 PID: 15690 Comm: syz-executor.3 Not tainted 4.19.197-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44 save_stack_trace_tsk+0x9c/0xf0 arch/x86/kernel/stacktrace.c:76 proc_pid_stack+0x202/0x350 fs/proc/base.c:456 proc_single_show+0xeb/0x170 fs/proc/base.c:755 seq_read+0x4be/0x1160 fs/seq_file.c:229 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 do_preadv fs/read_write.c:1071 [inline] __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1116 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0053d88188 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 000000000000037d RSI: 0000000020000500 RDI: 0000000000000004 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffaf4b161f R14: 00007f0053d88300 R15: 0000000000022000 The buggy address belongs to the page: page:ffffea00024755c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfff00000000000() raw: 00fff00000000000 0000000000000000 ffffffff02470101 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888091d57c80: 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 04 ffff888091d57d00: f2 04 f2 04 f2 00 00 f2 f2 00 00 00 f2 f2 f2 f2 >ffff888091d57d80: f2 00 00 00 f2 f2 f2 f2 f2 00 00 f3 f3 00 00 00 ^ ffff888091d57e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 ffff888091d57e80: f1 f1 00 f2 f2 f2 00 00 f3 f3 00 00 00 00 00 00 ==================================================================