Interview Question

What is buffer overflow?

A buffer overflow is an out-of-bounds access and causes undefined behavior.

💡 Concept ✅ Quick Revision ⚙ C

Answer

A buffer overflow occurs when code accesses beyond the bounds of an array or allocated object. • Out-of-bounds reads and writes have undefined behavior. • A write can corrupt nearby data or create a security vulnerability. • Track capacity and validate lengths before copying or indexing.

💡 C Example

char buffer[8]; const char source[] = "Hello"; if (sizeof source <= sizeof buffer) { memcpy(buffer, source, sizeof source); }

⚡ Quick Revision

A buffer overflow is an out-of-bounds access and causes undefined behavior.