Reject PCR property capability counts larger than the response

[aidangarske]

• TPM2_GetCapability with TPM_CAP_PCR_PROPERTIES looped over the count the TPM declared even after the response ran out. A bad
  count could keep the CPU busy for seconds, or return 127 entries that were never sent.
• The parse moves into TPM2_ParsePcrProperties. It stops when the response is used up and returns TPM_RC_SIZE if the count doesn't
  match what was sent.
• Adds a unit test covering a well-formed list, lists longer than the local array, and oversized counts.

Reported by Vishnu Ajith @Vishnu2707

ZD #22559

[Copilot]

Copilot review overview

🟢 Approval recommended

The parser now safely bounds attacker-controlled iteration and the targeted tests cover the reported failure modes.

Review effort: Balanced
Findings: None

What changed in this PR

Adds bounded parsing for PCR property capability responses, preventing oversized TPM-provided counts from causing excessive loops or fabricated entries.

Changes:

• Extracts PCR property parsing into a validated helper.
• Stops on packet exhaustion and returns TPM_RC_SIZE.
• Adds tests for valid, oversized, and truncated lists.

File	Description
src/​tpm2.c	Implements and integrates bounded PCR property parsing.
wolftpm/​tpm2_packet.h	Declares the test-visible parser.
tests/​unit_tests.c	Tests parser count handling and truncation.

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[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #620

Scan targets checked: wolftpm-src, wolftpm-bugs
Coverage: 1 of 3 in-scope changed file(s) opened by the reviewer; not opened: tests/unit_tests.c, wolftpm/tpm2_packet.h

Fenrir result: Approved ✅

No new issues found in the changed files.

Advisory only — this automated result does not count as a GitHub approval.

Review tier: Lite