include: Fix bug related to string.h's str[|n]dup #16766
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Defining `strdup` and `strndup` to (respectively) `nx_strdup` and `nx_strndup` should only apply when `CONFIG_BUILD_FLAT` is not set. Otherwise, the device may assert (if `CONFIG_DEBUG_ASSERTIONS` is enabled) at `DEBUGASSERT(mm_heapmember(heap, mem))` because `strdup` would allocate memory from the kernel heap, but freeing it would call `umm_free` (from the user heap). Signed-off-by: Tiago Medicci Serrano <tiago.medicci@espressif.com>
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acassis
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Jul 24, 2025
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Closing it due to #16768 |
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Summary
Defining
strdupandstrndupto (respectively)nx_strdupandnx_strndupshould only apply whenCONFIG_BUILD_FLATis not set. Otherwise, the device may assert (ifCONFIG_DEBUG_ASSERTIONSis enabled) atDEBUGASSERT(mm_heapmember(heap, mem))becausestrdupwould allocate memory from the kernel heap, but freeing it would callumm_free(from the user heap).Impact
Impact on user: Yes. Enables
ifconfigcommand to work as expected whenCONFIG_DEBUG_ASSERTIONSis enabled.Impact on build: Yes. If
CONFIG_BUILD_FLATis set and there is a user heap, its memory will be allocated from the user's heap (as well asfreerefers toumm_free).Impact on hardware: No.
Impact on documentation: No.
Impact on security: No.
Impact on compatibility: No.
Testing
This can be tested with
CONFIG_DEBUG_ASSERTIONSset, on a flat build config that enables the kernel heap (both kernel and user heaps available). For instance, testing can be performed by building the firmware and flashing it to a ESP32-S3 board with a PSRAM module (this example uses an ESP32-S3-DevKitC-1 v1.1 board with an ESP32-S3-WROOM-2 module). The device asserts after running theifconfigbefore applying this patch.Building
Running
Run the
ifconfigcommand:Results
Before
After