musl - musl - an implementation of the standard library for Linux-based systems

harden realloc/free to detect simple overflows

the sizes in the header and footer for a chunk should always match. if they don't, the program has definitely invoked undefined behavior, and the most likely cause is a simple overflow, either of a buffer in the block being freed or the one just below it. crashing here should not only improve security of buggy programs, but also aid in debugging, since the crash happens in a context where you have a pointer to the likely-overflowed buffer.

Diffstat (limited to 'src/malloc/malloc.c')

1 files changed, 6 insertions, 0 deletions