view mercurial/cext/__init__.py @ 40812:9cdd525d97b2 stable

revlog: fix out-of-bounds access by negative parents read from revlog (SEC)

82d6a35cf432 wasn't enough. Several callers don't check negative revisions
but for -1 (nullrev), which would directly lead to out-of-bounds read, and
buffer overflow could follow. RCE might be doable with carefully crafted
revlog structure, though I don't think this would be useful attack surface.