[LU-17062] Prevent use after free following *_decref_locked() usage

• Type: Bug
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.16.0, Lustre 2.15.5
• Severity: 3
• Assignee: Shaun Tancheff
• Reporter: Shaun Tancheff

Description

In rare cases when one of:
lnet_peer_net_decref_locked
lnet_peer_decref_locked
lnet_peer_ni_decref_locked
Actually destroys the object it is not safe to use.
Update the functions to return true when the object is deleted and ensure the object is not referenced (used) after it has been kfree()'d.

Issue Links

• is related to: LU-18320 interop: sanity-lnet test_226: ASSERTION( list_empty(&lpni->lpni_peer_nis) ) failed