FWIW, I was able to apply bb96fc4295 cleanly to the current 20.04 package (2:3.3.16-1ubuntu2) and it works for me.
apt-get -y source procps && cd procps-* curl -fSsL -o debian/patches/sc_arg_max https://gitlab.com/procps-ng/procps/-/commit/bb96fc4295.patch echo sc_arg_max >>debian/patches/series dch --local myorg 'Apply patch: "pgrep: check sanity of SC_ARG_MAX"' debuild -us -uc -G -i -tc
FWIW, I was able to apply bb96fc4295 cleanly to the current 20.04 package (2:3.3.16-1ubuntu2) and it works for me.
apt-get -y source procps && cd procps-* patches/ sc_arg_ max https:/ /gitlab. com/procps- ng/procps/ -/commit/ bb96fc4295. patch patches/ series
curl -fSsL -o debian/
echo sc_arg_max >>debian/
dch --local myorg 'Apply patch: "pgrep: check sanity of SC_ARG_MAX"'
debuild -us -uc -G -i -tc