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POMystery heap corruption, why?
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copied!<p>I've had a bug in my code for some time that I can't figure out. Maybe I'm just blind, but this bug doesn't make much sense, because from what I can see, this code is flawless. I speculate that there may be corruption from somewhere else, but I figured I'd paste my problem code here just in case.</p> <p>I know there is heap corruption because I get the standard <strong>Error</strong> message followed by a free() invalid next size message. I've included what I feel to be relevant. Heap corruption occurs on the second free(FileBuf);</p> <pre><code>while ((DirPtr = readdir(ProcDir))) { if (AllNumeric(DirPtr->d_name) && atoi(DirPtr->d_name) >= InObj->ObjectPID && atoi(DirPtr->d_name) <= InObj->ObjectPID + 10) /*Search 10 PIDs forward.*/ { char TChar; snprintf(FileName, sizeof FileName, "/proc/%s/cmdline", DirPtr->d_name); if (!(Descriptor = fopen(FileName, "r"))) { closedir(ProcDir); return 0; } FileBuf = malloc(MAX_LINE_SIZE); /*Scroll further down to find the free()s.*/ for (Inc = 0; (TChar = getc(Descriptor)) != EOF && Inc < MAX_LINE_SIZE - 1; ++Inc) { FileBuf[Inc] = TChar; } FileBuf[Inc] = '\0'; fclose(Descriptor); for (Inc = 0, Inc2 = NumSpaces; Inc2 != 0; ++Inc) { /*We need to replace the NUL characters with spaces.*/ if (FileBuf[Inc] == '\0') { --Inc2; FileBuf[Inc] = ' '; } } if (!strcmp(FileBuf, InObj->ObjectStartCommand)) { unsigned long RealPID; free(FileBuf); FileBuf = NULL; snprintf(FileName, sizeof FileName, "%s", DirPtr->d_name); closedir(ProcDir); RealPID = atoi(FileName); if (UpdatePID) { InObj->ObjectPID = RealPID; } return RealPID; } /*And here is the problem.*/ free(FileBuf); } } closedir(ProcDir); return 0; </code></pre>

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