tools: mkimage: fix get_basename crash on paths with dotted directories

The get_basename() helper in tools/fit_image.c searches the entire input
path for the last '/' and the last '.' independently. When the last '.'
falls at an offset earlier than the last '/' (for example "./mydt",
"a.b/c", or "sub.d/leaf"), 'end' points before 'start' and the computed
length is negative. The subsequent size check uses signed comparison so
the negative value passes through unchanged, and memcpy() is then called
with that length implicitly cast to size_t, which segfaults.

Restrict the dot search to the substring that follows the last slash so
that only an extension in the filename component can become the end of
the basename. This matches the function's stated intent of stripping an
extension from the leaf, and keeps the existing behaviour for typical
inputs such as "arch/arm/dts/foo.dtb".

Reproducer that previously segfaulted and now produces a valid image:

  echo dummy > kernel.bin
  echo dummy > ./mydt
  ./tools/mkimage -f auto -A arm -O linux -T kernel -C none \
                  -a 0x80000000 -e 0x80000000 -n test \
                  -d kernel.bin -b ./mydt out.itb

Signed-off-by: Aristo Chen <[email protected]>
Reviewed-by: Quentin Schulz <[email protected]>

0 files changed, 0 insertions, 0 deletions