What does HRESULT 0x80093001 (OSS_MORE_BUF) mean?

 
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CRYPT_E_OBJECT_LOCATOR_OBJECT_NOT_FOUND OSS_NEGATIVE_UINTEGER

OSS_MORE_BUF

OSS_MORE_BUF (0x80093001) is an OSS ASN.1 runtime result for caller-owned output buffer exhaustion. The encoder or decoder needs more room than the caller supplied; pointer-referenced fields can make a PDU larger than sizeof its top-level C structure. Because requested versus allocated byte count is central to this condition, Microsoft’s HRESULT range and the OSS Nokalva return-code documentation should be read together. Start the investigation by recording whether automatic allocation was disabled, then separate the encoded value from generated artifacts, call arguments, and the runtime package actually loaded by the process.

Locate the exact codec boundary

At the caller-owned output buffer exhaustion boundary, capture the first OSS function returning the value and note whether the operation was encode, decode, copy, compare, constraint validation, or trace setup. Preserve the selected PDU, encoding rules, and the PDU fields that own strings, arrays, or off-shoot structures; otherwise an outer certificate or security wrapper may hide the useful codec result behind a generic failure.

Evidence worth preserving

RecordDiagnostic value
requested versus allocated byte countLocates the concrete message, allocation, module, or API boundary
whether automatic allocation was disabledSeparates payload-dependent behavior from build and process state
the PDU fields that own strings, arrays, or off-shoot structuresMakes the comparison reproducible without rewriting the original artifact

A controlled way to reproduce it

  1. ask the runtime to determine the encoded length before allocating
  2. repeat with runtime allocation as a control
  3. place guard bytes around a test buffer to detect overwrite assumptions

Keep the original bytes or object graph unchanged while testing ask the runtime to determine the encoded length before allocating. A change in whether automatic allocation was disabled after reload, plugin replacement, restart, or schema deployment is evidence about runtime state, not permission to discard the reproducer. When the PDU fields that own strings, arrays, or off-shoot structures points to one message, retain a cryptographic hash and the smallest safe sample instead of logging certificate, subscriber, credential, or private-key material.

What not to confuse it with: the result

Unlike OSS_MORE_INPUT, the complete encoded input may be present; the shortage is in storage for the produced representation.

Decision matrix

Controlled observationConclusion it supports
ask the runtime to determine the encoded length before allocatingA changed outcome isolates the first proposed control instead of a blind retry
requested versus allocated byte count differs between success and failureThe difference localizes the caller-owned output buffer exhaustion boundary before unrelated settings are changed
An independent decoder accepts the same artifactInspect generated schema, selected rules, ABI, and optional OSS modules before declaring the bytes invalid
A fresh control object changes the outcomeInvestigate initialization, lifecycle, allocator ownership, configuration mutation, and concurrent access

Instrumentation

Record the full 32-bit HRESULT and lower OSS return number together with operation direction, symbolic PDU, encoding rule, byte count, and generated-table identifier. Where requested versus allocated byte count can expose sensitive content, a hash plus a bounded structural excerpt is safer than the complete payload. Use whether automatic allocation was disabled together with OSS module paths and versions logged once per process so packaging differences can be correlated without flooding normal diagnostics.

Exit criteria: the result

Size from the codec contract rather than from the host-language structure, then prove the same PDU succeeds without truncation. A recovery test built around ask the runtime to determine the encoded length before allocating should replay the same operation under the same schema and encoding rule, retain one deliberately invalid control, and verify ownership and cleanup after both outcomes. Success after an unexamined retry is not proof that requested versus allocated byte count now satisfies the codec contract.

Technical references


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