syzbot


KMSAN: uninit-value in cp_new_stat

Status: closed as invalid on 2018/04/16 10:01
Subsystems: fs
[Documentation on labels]
First crash: 2478d, last: 2478d

Sample crash report:
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
==================================================================
BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 [inline]
BUG: KMSAN: uninit-value in cp_new_stat+0x699/0x9a0 fs/stat.c:330
CPU: 1 PID: 1859 Comm: udevd Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 kmsan_internal_check_memory+0x125/0x1d0 mm/kmsan/kmsan.c:1157
 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199
 copy_to_user include/linux/uaccess.h:184 [inline]
 cp_new_stat+0x699/0x9a0 fs/stat.c:330
 SYSC_newstat+0x2ef/0x330 fs/stat.c:341
 SyS_newstat+0x46/0x70 fs/stat.c:333
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x7f9a06f7ec65
RSP: 002b:00007ffecd123868 EFLAGS: 00000246 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000001a3d250 RCX: 00007f9a06f7ec65
RDX: 00007ffecd123880 RSI: 00007ffecd123880 RDI: 00007ffecd123d10
RBP: 00007ffecd124170 R08: 000000000041f4f1 R09: 00007f9a06fd57d0
R10: 7269762f73656369 R11: 0000000000000246 R12: 0000000000000004
R13: 00007ffecd124177 R14: 0000000001a3d1d0 R15: 0000000001a3d250

Local variable description: ----tmp@cp_new_stat
Variable was created at:
 cp_new_stat+0x60/0x9a0 fs/stat.c:297
 SYSC_newstat+0x2ef/0x330 fs/stat.c:341

Bytes 80-84 of 144 are uninitialized
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/16 05:55 https://github.com/google/kmsan.git master 35ff515e4bda 7a67784c .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.