Negative -map processing iterates previously parsed stream map entries
and dereferences input_files[m->file_index]->ctx->streams[m->stream_index]
without validating that stream_index is in range.
A malformed earlier map can leave m->stream_index negative, which causes
an out-of-bounds read when a later negative map walks existing entries.
Check that stream_index is non-negative and below nb_streams before
calling stream_specifier_match().
*Vulnerability reported by Zhenpeng (Leo) Lin at depthfirst*
*Patch validated by Zheng Yu at depthfirst*
Fixes: DFVULN-695
(cherry picked from commit 25a98586cc)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
depthfirst-dev[bot]
dc3742fd7f