Test fix for buffer overflow

[sei-vsarvepalli]

This pull request updates the way strings are copied into a buffer in heap_example.c to prevent buffer overflows. The unsafe strcpy call has been replaced with a safer alternative.

Memory safety improvement:

• Replaced the unsafe strcpy with strncpy, and commented out the original line, to avoid writing past the end of the allocated buffer. (heap_example.c)

[Copilot]

Pull request overview

This pull request attempts to fix a buffer overflow vulnerability by replacing strcpy with strncpy in a heap-allocated buffer example. However, the implementation contains critical bugs that prevent it from compiling and working correctly.

Changes:

• Commented out the unsafe strcpy call
• Added strncpy with an invalid len() function call that does not exist in C

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[Copilot]

Using strncpy without explicit null-termination is unsafe. The strncpy function does not guarantee null-termination if the source string is longer than or equal to the specified size. After the strncpy call, you should explicitly null-terminate the buffer by setting buffer[15] = '\0'; (or buffer[size - 1] = '\0'; where size is 16) to ensure the string is properly terminated before using it with printf.

Suggested change

	strncpy(buffer, "This string is definitely longer than 16 bytes", len(buffer) - 1);
	strncpy(buffer, "This string is definitely longer than 16 bytes", 15);
	buffer[15] = '\0';

[Copilot]

Consider using snprintf instead of strncpy for safer string handling. Unlike strncpy, snprintf always null-terminates the result and is more appropriate for string copying. For example: snprintf(buffer, 16, "%s", "This string is definitely longer than 16 bytes"); would properly handle both truncation and null-termination.

[Copilot]

The function len() does not exist in standard C. This code will fail to compile. For a heap-allocated buffer of known size, you should use the constant 16 directly (the allocated size from line 6), or better yet, define a constant for the buffer size and use it consistently.