Last modified on 23 March 2014, at 13:36

Linux Applications Debugging Techniques/Heap corruption

Electric FenceEdit

Electric Fence is still the reference for dealing with heap corruption, even if not maintined for a while. RedHat ships a version that can be used as an interposition library.

Drawback: might not work with code that uses mmap() to allocate memory.

DumaEdit

Duma is a fork of Electric Fence.

glibc builtinEdit

man (3) malloc: Recent versions of Linux libc (later than 5.4.23) and GNU libc (2.x) include a malloc implementation which is tunable via environment variables. When MALLOC_CHECK_ is set, a special (less efficient) implementation is used which is designed to be tolerant against simple errors, such as double calls of free() with the same argument, or overruns of a single byte (off-by-one bugs). Not all such errors can be protected against, however, and memory leaks can result. If MALLOC_CHECK_ is set to 0, any detected heap corruption is silently ignored and an error message is not generated; if set to 1, the error message is printed on stderr, but the program is not aborted; if set to 2, abort() is called immediately, but the error message is not generated; if set to 3, the error message is printed on stderr and program is aborted. This can be useful because otherwise a crash may happen much later, and the true cause for the problem is then very hard to track down.

AddressSanitizerEdit

A fast memory error detector via -fsanitize=address , with a recent gcc (since 4.8) or clang (since 3.1). Memory access instructions will be instrumented to detect heap-, stack-, and global-buffer overflow as well as use-after-free bugs. To get nicer stacktraces, use -fno-omit-frame-pointer. The AddressSanitizer is available on IA-32/x86-64/x32/PowerPC/PowerPC64 GNU/Linux and on x86-64 Darwin.