ellis@flairvax.UUCP (Michael Ellis) (09/29/83)
Vnews 2.10.1 consistently aborts with a core dump on our Ann Arbor Ambassador terminals whenever they are configured for a 60 line display. We run 4.1(a)bsd, and I've changed the MAXPLEN #define to accomodate the larger size page. The bug does not manifest itself until an article fills the entire screen. No problems with 48, 40 ... or smaller configurations, though. I'm currently trying to track down the problem, which is difficult since the stack gets screwed. All sdb can tell me is that vnews was executing in `_amove'. Anyone else with large screens see this bug? Michael Ellis ..!decwrl!flairvax!ellis Mellis@SRI-KL
ka@spanky.UUCP (10/02/83)
The core dump is caused by an array overflow. The routine _amove contains the declarations: char rel[MAXPLEN + MAXLLEN + 50]; /* longest move is full screen */ char ho[MAXPLEN + MAXLLEN + 50]; This code assumes that all relative cursor motions can be performed using a single character sequence. This assumption is reasonable for horizontal motions but not for vertical ones. A simple fix is to change the array sizes to "MAXPLEN * 2 + MAXLLEN + 50", which will probably work for almost all terminals. A better fix would of course be to have the plodput routine check for overflow of array bounds. Kenneth Almquist