[LU-4689] mds returns EINVAL for hsm commands if fsname is 8-byte aligned

• Status: Resolved
• Project: Lustre
• Affects Version/s: Lustre 2.5.0, Lustre 2.6.0
• Fix Version/s: Lustre 2.6.0, Lustre 2.5.1
• Type: Bug
• Priority: Critical
• Reporter: Peng Tao
• Assignee: James Nunez (Inactive)
• Resolution: Fixed
• Labels: HSM, mn4, patch

Environment

b2_5 and master have the same issue.

• Severity: 3

Description

If a filesystem name is 8-byte aligned, all HSM commands will get -EINVALID. The root cause is in following code:

/* Return pointer to first hai in action list */
static inline struct hsm_action_item *hai_first(struct hsm_action_list *hal)
{
        return (struct hsm_action_item *)(hal->hal_fsname +
                                          cfs_size_round(strlen(hal-> \
                                                                hal_fsname)));
}

hal_fsname is a string terminated with NULL. If strlen(hal->hal_fsname) is 8 aligned, hai_first() ends up eating the terminating NULL character.

Now when the caller first time call hai_first() and set proper value to the returning first hsm_action_item, it ends up appending some non-NULL characters at the address of hal_fsname + strlen(hal_fsname). The side effect is that the next time someone calls hal_first(), strlen(hal->hal_fsname) is larger than the first time. That would result in misplacement of hsm_action_item and causes hal_is_sane() check to fail.

Comments

[Peng Tao]

patch tracking at http://review.whamcloud.com/9431

[Peter Jones]

James

Could you please look after this one?

Thanks

Peter

[Peng Tao]

The patch for master has been landed. I ported it to b2_5 that has the same issue. Please see http://review.whamcloud.com/9468

[Jodi Levi (Inactive)]

Patch landed to Master and will be landed to b2_5