Subj : src/sbbs3/postmsg.cpp
To   : Git commit to main/sbbs/master
From : Rob Swindell (on Windows)
Date : Sun May 07 2023 11:22 pm

https://gitlab.synchro.net/main/sbbs/-/commit/4a86ab8768e486a58d22d55e
Modified Files:
	src/sbbs3/postmsg.cpp
Log Message:
Bounds-check subnum in savemsg()

It's possible to use savemsg() (from JS MsgBase.save_msg()) to add a message
to a message base that's not a sub-board (not configured in SCFG->Message
Areas and not the "mail" base), but in that case, savemsg() would dereference
an invalid sub in the scfg->sub array and crash. So use is_valid_subum()
to insure the subnum is a valid sub before using as an index.

.