[LU-5431] lmv_intent_lookup() leaks lock if lmv_revalidate_slaves() fails

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.6.0, Lustre 2.7.0
• Labels: dne2
• Severity: 3
• Assignee: John Hammond
• Reporter: John Hammond

Description

In lmv_intent_lookup() if md_intent_lock() succeeds but lmv_revalidate_slaves() fails then the lock referenced by it->d.lustre.it_lock_handle is leaked.

        rc = md_intent_lock(tgt->ltd_exp, op_data, it, reqp, cb_blocking,
                            extra_lock_flags);
        if (rc < 0)
                RETURN(rc);

        if (*reqp == NULL) {
                /* If RPC happens, lsm information will be revalidated                    
                 * during update_inode process (see ll_update_lsm_md) */
                if (op_data->op_mea2 != NULL) {
                        rc = lmv_revalidate_slaves(exp, NULL, op_data->op_mea2,
                                                   cb_blocking,
                                                   extra_lock_flags);
                        if (rc != 0)
                                RETURN(rc);
                }
                RETURN(rc);
        }

This was found through manual code audit.

Comments

[Jodi Levi (Inactive)]

Patch landed to Master.

[John Hammond]

A bit of instrumentation shows that this is easy to hit running racer.