vtfontcvt: improve .bdf verification

Previously we would crash if the BBX y-offset was outside of the font
bounding box.

Reported by:	afl
MFC with:	r349100
Event:		Berlin Devsummit 2019
Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Ed Maste 2019-06-16 13:35:53 +00:00
parent c6e475ff5a
commit fd0e3f7c98

View File

@ -383,7 +383,8 @@ parse_bdf(FILE *fp, unsigned int map_idx)
sscanf(ln + 4, "%d %d %d %d", &bbw, &bbh, &bbox,
&bboy) == 4) {
if (bbw < 1 || bbh < 1 || bbw > fbbw || bbh > fbbh ||
bbox < fbbox || bboy < fbboy)
bbox < fbbox || bboy < fbboy ||
bbh + bboy > fbbh + fbboy)
errx(1, "broken bitmap with BBX %d %d %d %d at line %u",
bbw, bbh, bbox, bboy, linenum);
bbwbytes = howmany(bbw, 8);