[LU-12244] lfs check subcommand no longer works as non-root user

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Affects Version/s: Lustre 2.10.6
• Labels: llnl
• Environment: Client/Server: lustre-2.10.6_2.chaos-1.ch6.x86_64 ; kernel: 3.10.0-957.5.1.3chaos.ch6.x86_64
• Severity: 3
• Assignee: Peter Jones
• Reporter: Cameron Harr

Description

With the Lustre 2.10 client, non-root users appear to no longer be able to run "lfs check <servers|osts|mds>". Strace of the command shows a "Permission denied" error accessing /sys/kernel/debug/lustre/devices, resulting in the following error at runtime: error: check: mds status failed

Our Operations staff w/o root access needs "lfs check ..." functionality to monitor and fix file system issues, so fixing this issue would helpful for us.

statfs("/sys/kernel/debug/", {f_type=DEBUGFS_MAGIC, f_bsize=4096, f_blocks=0, f_bfree=0, f_bavail=0, f_files=0, f_ffree=0, f_fsid={0, 0}, f_namelen=255, f_frsize=4096, f_flags=ST_VALID|ST_RELATIME}) = 0
stat("/sys/fs/lnet/devices", 0x7fffffff8760) = -1 ENOENT (No such file or directory)
stat("/sys/fs/lustre/devices", 0x7fffffff8760) = -1 ENOENT (No such file or directory)
stat("/sys/kernel/debug/lnet/devices", 0x7fffffff8740) = -1 EACCES (Permission denied)
stat("/sys/kernel/debug/lustre/devices", 0x7fffffff8740) = -1 EACCES (Permission denied)
stat("/proc/fs/lnet/devices", 0x7fffffff8760) = -1 ENOENT (No such file or directory)
stat("/proc/fs/lustre/devices", 0x7fffffff8760) = -1 ENOENT (No such file or directory)
stat("/proc/sys/lnet/devices", 0x7fffffff8760) = -1 ENOENT (No such file or directory)
stat("/proc/sys/lustre/devices", 0x7fffffff8760) = -1 ENOENT (No such file or directory)
write(2, "error: check: mds status failed\n", 32error: check: mds status failed
) = 32
exit_group(2)                           = ?
+++ exited with 2 +++

Issue Links

• is related to: LU-11850 Relocating /proc/fs/lustre/ost to /sys/kernel/debug/lustre/ost prevents non-root access
• is related to: LU-8066 Move lustre procfs handling to sysfs and debugfs.

Comments

[Peter Jones]

Ok - now this is fixed on b2_12

[Peter Jones]

I think that once the current b2_12-next branch lands that this really will be complete.

[Peter Jones]

You are correct - sorry.

[Olaf Faaland]

Peter,
I do not see that this patch landed to 2.12.2 even though it was backported to 2.10.

[faaland1@hefe branch:2.10.6-llnl lustre-210] $git lg wcrev/b2_12 | grep LU-8066 | grep iterate
[faaland1@hefe branch:2.10.6-llnl lustre-210] $git lg wcrev/b2_10 | grep LU-8066 | grep iterate
* e55cd4f LU-8066 utils: have llapi_target_iterate use sysfs tree

https://review.whamcloud.com/#/c/34781/

Has a +2 but has not landed due to undiagnosed test failures, last activity May 8.

[Peter Jones]

I believe that this issue is fixed in both 2.10.8 and 2.12.2 so the ticket can now be considered RESOLVED

[Olaf Faaland]

For our own recordkeeping, our local ticket: TOSS-4503

[Olaf Faaland]

Yep, that patch worked without any other patches or modification.

[Olaf Faaland]

Andreas, we haven't tried it, but we can do so today and post back.

[Andreas Dilger]

Cameron, did you try out the patch for b2_10? Did it solve your problem? It only affects the userspace tools on the client, so you wouldn't need to upgrade all of the kernel modules or take an outage to install it.

[Cameron Harr]

... And I had searched only on 2.10. Thanks.