[LU-9753] OFD destroy non-orphan OST-object because of overflow

• Type: Bug
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.10.1, Lustre 2.11.0
• Severity: 3
• Assignee: nasf (Inactive)
• Reporter: nasf (Inactive)

Description

In ofd_create_hdl(), the logic will compare the OST stroed LAST_ID with the MDT given one: if the difference exceeds some threshold, then it will trust the OST LAST_ID directly and reset the MDT side value with the OST one. Otherwise, the orphan OST-objects will be destroyed.

Unfortunately, both the OST stored LAST_ID and MDT given one are 64 bits, but the @diff variable is only 32 bits, and if the OST side value is too larger than the MDT side, then the @diff will overflow. That will misguide the OST to destroy useful OST-objects by wrong.