Fix null pointer dereference in Matroska parser on file open failure#2171
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apoorvdarshan wants to merge 1 commit intoCCExtractor:masterfrom
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Fix null pointer dereference in Matroska parser on file open failure#2171apoorvdarshan wants to merge 1 commit intoCCExtractor:masterfrom
apoorvdarshan wants to merge 1 commit intoCCExtractor:masterfrom
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create_file() returns the result of fopen() which can be NULL if the file cannot be opened. matroska_loop() never checked this, passing the NULL pointer into matroska_parse() where it is immediately used in feof(), causing a crash. Add a NULL check and return an error.
cfsmp3
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Mar 7, 2026
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cfsmp3
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Same issue as the feedback on #2157: use fatal(EXIT_READ_ERROR, ...) instead of mprint() + return. If the input file can't be opened, the program should exit with a proper error code, not silently return and appear to succeed. The very next error check in this function (malloc for sub_tracks) uses fatal() — be consistent.
Also remove the CHANGES.TXT entry — this is an internal fix, not a user-reported bug.
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Summary
create_file()returns the result offopen()without checking for NULLmatroska_loop()passes this directly intomatroska_parse(), which callsfeof()on the NULL pointer, crashing the programcreate_file()that prints an error, freesmkv_ctx, and returns-1Test plan