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KMSAN: uninit-value in warn_bad_vsyscall

Status: auto-closed as invalid on 2020/11/27 13:26
Subsystems: kernel
[Documentation on labels]
First crash: 1336d, last: 1336d

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in warn_bad_vsyscall+0x54e/0x5a0 arch/x86/entry/vsyscall/vsyscall_64.c:79
CPU: 0 PID: 10983 Comm: syz-executor.5 Not tainted 5.8.0-rc5-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+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 warn_bad_vsyscall+0x54e/0x5a0 arch/x86/entry/vsyscall/vsyscall_64.c:79
 __exc_page_fault+0xac/0x450 arch/x86/mm/fault.c:1428
 exc_page_fault+0x45/0x50 arch/x86/mm/fault.c:1390
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:550
RIP: 0010:warn_bad_vsyscall+0x2ec/0x5a0 arch/x86/entry/vsyscall/vsyscall_64.c:79
Code: 02 48 89 45 80 4d 85 ff 0f 85 b7 02 00 00 48 8b 03 48 89 45 c0 48 89 df e8 f1 6e 35 01 4c 8b 00 4c 89 45 d0 8b 02 48 89 45 88 <49> c7 04 24 00 00 00 00 48 8b 95 20 ff ff ff 49 89 54 24 08 48 8b
RSP: 0018:ffff888108ce3c28 EFLAGS: 00010086
RAX: 0000000004cb00cb RBX: ffff888108ce3c88 RCX: 00000001088e3c88
RDX: ffff8881088e3c88 RSI: 0000000000000420 RDI: ffff888108ce3c88
RBP: ffff888108ce3c40 R08: ffffffffffffffff R09: ffff88812fffa000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888108ce3c80 R15: 0000000000000000
 exc_invalid_op+0x4e/0x80 arch/x86/kernel/traps.c:258
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:548
RIP: 0010:emulate_vsyscall+0x252/0x2f20 arch/x86/entry/vsyscall/vsyscall_64.c:134
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RSP: 0018:ffff888108ce3d28 EFLAGS: 00010046
RAX: ffff8881afe4c6d8 RBX: ffff888108ce3e78 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000420 RDI: ffff8881afe4bd00
RBP: ffff888108ce3d40 R08: ffffea000000000f R09: ffff88812fffa000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8881afe4c6d8 R14: ffff8881afe4c6d8 R15: 0000000000000000
 exc_general_protection+0x90/0x6d0 arch/x86/kernel/traps.c:523
 asm_exc_general_protection+0x1e/0x30 arch/x86/include/asm/idtentry.h:544
RIP: 0010:find_timens_vvar_page arch/x86/entry/vdso/vma.c:130 [inline]
RIP: 0010:vvar_fault+0xc30/0xca0 arch/x86/entry/vdso/vma.c:236
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RSP: 0018:ffff888108ce3f20 EFLAGS: 00010257
RAX: ffff8881084e3fa8 RBX: ffff8881afe4c6d8 RCX: 00000001088e3fa8
RDX: ffff8881088e3fa8 RSI: 0000000000000420 RDI: ffff888108ce3f58
RBP: ffff888108ce3f48 R08: ffffea000000000f R09: ffff88812fffa000
R10: 0000000000000004 R11: ffff8881afe4bd00 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888108ce3f58 R15: 0000000000000000
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4171fb
Code: Bad RIP value.
RSP: 002b:000000000169fd80 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00000000004171fb
RDX: 0000000040000001 RSI: 000000000169fde0 RDI: ffffffffffffffff
RBP: 000000000169fde0 R08: 0000000000000000 R09: 0000000001877940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000040000001
R13: 000000000169fde0 R14: 00000000000f8f06 R15: 000000000169fdf0

------------[ cut here ]------------
slab index 41072 out of bounds (425) for stack id 8236a070
WARNING: CPU: 0 PID: 10983 at lib/stackdepot.c:235 stack_depot_fetch+0x2d/0x60 lib/stackdepot.c:234

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/29 13:18 https://github.com/google/kmsan.git master 3b3ea6028136 d5a3ae1f .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.