When -B or -I are used, change() evaluates the lines in a hunk to determine if it is a hunk that should be ignored. It does this by reading each candidate line into a mallocated buffer via preadline() and then calling ignoreline(). Previously the buffer was freed as a side effect of ignoreline_pattern() called from ignoreline(). However, if only -B was specified, then ignoreline_pattern() was not called and the lines were leaked. If both options were specified, then ignoreline_pattern() was called before checking for a blank line so that the second check was a use after free. To fix, pull the free() out of ignoreline_pattern() and instead do it up in change() so that is paired with preadline(). While here, simplify ignoreline() by checking for the -B and -I cases individually without a separate clause for when both are set. Also, do the cheaper check (-B) first, and remove a false comment (this function is only called if at least one of -I or -B are specified). Reviewed by: emaste Reported by: GCC 12 -Wuse-after-free Differential Revision: https://reviews.freebsd.org/D36822 |
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tests | ||
diff.1 | ||
diff.c | ||
diff.h | ||
diffdir.c | ||
diffreg.c | ||
Makefile | ||
pr.c | ||
pr.h | ||
TODO | ||
xmalloc.c | ||
xmalloc.h |