[PR] mm/kasan: prevent recursive report overflow [nuttx]

["Jackapyun (via GitHub)" <gi...@apache.org>]

Jackapyun opened a new pull request, #18042:
URL: https://github.com/apache/nuttx/pull/18042

   ## Summary
   
   This PR addresses a critical stack overflow issue in the KASAN (Kernel Address Sanitizer) error reporting mechanism when the report handler recursively triggers additional KASAN checks.
   
   ### Problem
   When `kasan_report()` is executing and calls `_alert()` for error reporting, the logging function may trigger additional memory access operations that can fail KASAN checks. This causes recursive re-entry into the KASAN report handler, leading to stack overflow and suppressing the original error report.
   
   ### Solution
   The fix implements a dual-approach strategy:
   
   1. **Call `kasan_stop()` before reporting**: Halts all KASAN checks when entering the panic path, preventing recursive checks during error message printing
   2. **Reuse `dump_only` flag efficiently**: Consolidates the panic/non-panic decision logic into a single flag, ensuring consistent behavior without additional stack usage
   
   ### Key Changes
   - Extract `dump_only` flag calculation at the beginning of `kasan_report()` 
   - Call `kasan_stop()` only when panic reporting is needed (before `_alert()`)
   - Reuse the flag for both panic decision and stack dump logic
   
   ---
   
   ## Impact
   
   ### Stability
   - ✅ Eliminates stack overflow risk from recursive KASAN reports
   - ✅ Preserves original error reporting despite recursive triggers
   - ✅ Reduces stack memory usage in error paths
   
   ### Compatibility
   - ✅ No breaking API changes
   - ✅ No impact on non-KASAN builds
   - ✅ Maintains existing panic/dump behavior based on configuration
   
   ### Code Quality
   - ✅ Improves code maintainability by eliminating duplicate logic
   - ✅ Reduces code duplication in panic decision handling
   - ✅ Clear separation of concerns in error handling flow
   


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Re: [PR] mm/kasan: prevent recursive report overflow [nuttx]

["xiaoxiang781216 (via GitHub)" <gi...@apache.org>]

xiaoxiang781216 merged PR #18042:
URL: https://github.com/apache/nuttx/pull/18042


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