system/nxrecorder: Fix null pointer dereference in argument parsing#3435
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simbit18 merged 1 commit intoapache:masterfrom Mar 26, 2026
Merged
system/nxrecorder: Fix null pointer dereference in argument parsing#3435simbit18 merged 1 commit intoapache:masterfrom
simbit18 merged 1 commit intoapache:masterfrom
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When a command has no arguments (e.g., 'q', 'quit', 'stop'), the strtok_r() function returns NULL for the arg parameter. The argument trimming loop was dereferencing this NULL pointer without checking, causing undefined behavior and system hang on ESP32-S3. This commit adds a null check before dereferencing the arg pointer in the leading space trimming loop. Tested on ESP32-S3 (lckfb-szpi-esp32s3) - quit command now works correctly. Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
xiaoxiang781216
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Mar 26, 2026
cederom
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Mar 26, 2026
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cederom
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Thank you @JianyuWang0623 :-)
simbit18
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Mar 26, 2026
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Summary
system/nxrecorder/nxrecorder_main.ccontains a command parsing loop that trims leading spaces from theargstring returned bystrtok_r(). When a command takes no arguments (e.g.,q,quit,stop),strtok_r()returnsNULLforarg. The original loopwhile (*arg == ' ')unconditionally dereferencedargwithout a null check, causing undefined behavior — manifesting as a system hang on ESP32-S3.The fix adds a null guard before the dereference:
Impact
nxrecorder_main.cargument parsing.nxrecorderwhere no-argument commands (q,quit,stop, etc.) are used interactively.Testing
lckfb-szpi-esp32s3:nshor equivalent config)quit(andq,stop) command innxrecorderno longer causes a system hang.quitwith no arguments caused a null pointer dereference and the system hung.quitexits cleanly as expected.