If this function returns an error after ff_sws_graph_add_pass() has been
called, and the pass->free callback is therefore already set up to free the
context, the graph will end up freed twice: once by the pass->free callback
(during ff_sws_graph_free()), and once before that by failure path of the
caller (e.g. add_legacy_sws_pass(), or init_legacy_subpass() itself for
cascaded contexts.)
The solution is to redefine the ownership of SwsGraph to pass clearly from
the caller of add_legacy_sws_pass() to init_legacy_subpass(), which can then
deal with appropriately freeing the context conditional on whether or not the
pass was already registered in the pass list.
Reported-by: 김영민 <kunshim@naver.com>
Signed-off-by: Niklas Haas <git@haasn.dev>
4ede75b5f4