Sanitizers

Overview

A number of sanitizers are available in C compilation toolchains that add additional instrumentation into a program. Such instrumentation can be used to detect a wide variety of hard-to-find bugs.

Address Sanitizer

The AddressSanitizer (i.e. ASan) modifies a program to detect memory errors at runtime. These include, but are not limited to:

• Out-of-bounds accesses to heap, stack, and globals
• Use-after-free
• Double-frees and invalid frees

Memory Sanitizer

The MemorySanitizer (i.e. MSan) modifies a program at compile time to catch uninitialized memory use.

Thread Sanitizer

The ThreadSanitizer (i.e. TSan) modifies a program to detect data races.

Undefined Behavior Sanitizer

The UndefinedBehaviorSanitizer (i.e. UBSan) modifies a program at compile time to catch various kinds of undefined behavior during program execution. This includes, but is not limited to, the following checks:

• Array subscript out of bounds
• Bitwise shifts out of bounds for their data type
• Dereferencing misaligned or null pointers
• Signed integer overflow
• Conversion to, from, or between floating-point types which would overflow the destination