From 9c9d0d90512f0e5950b179d1a07f717ad7c8fe28 Mon Sep 17 00:00:00 2001 From: Ed Maste Date: Wed, 22 Sep 2021 14:41:00 -0400 Subject: [PATCH] vt: bound buffer access in redraw optimization PR: 248628 Reported by: oleg Reviewed by: cem, oleg (both earlier) Fixes: ee97b2336aa4 ("Speed up vt(4) by keeping...") MFC after: 3 days Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D32059 (cherry picked from commit dbc7ca59451561a179f9852642e13ef024169d84) (cherry picked from commit e4fcff8ee124f8faed2f1fcc1e15b7ae6906d4d7) Approved by: so Security: FreeBSD-SA-22:01.vt --- sys/dev/vt/hw/fb/vt_fb.c | 6 ++++++ sys/dev/vt/hw/vga/vt_vga.c | 6 ++++++ 2 files changed, 12 insertions(+) diff --git a/sys/dev/vt/hw/fb/vt_fb.c b/sys/dev/vt/hw/fb/vt_fb.c index 62a52dd9e01..5c14be1c15b 100644 --- a/sys/dev/vt/hw/fb/vt_fb.c +++ b/sys/dev/vt/hw/fb/vt_fb.c @@ -354,6 +354,9 @@ vt_fb_bitblt_text(struct vt_device *vd, const struct vt_window *vw, VTBUF_ISCURSOR(&vw->vw_buf, row, col), &fg, &bg); z = row * PIXEL_WIDTH(VT_FB_MAX_WIDTH) + col; + if (z >= PIXEL_HEIGHT(VT_FB_MAX_HEIGHT) * + PIXEL_WIDTH(VT_FB_MAX_WIDTH)) + continue; if (vd->vd_drawn && (vd->vd_drawn[z] == c) && vd->vd_drawnfg && (vd->vd_drawnfg[z] == fg) && vd->vd_drawnbg && (vd->vd_drawnbg[z] == bg)) @@ -404,6 +407,9 @@ vt_fb_invalidate_text(struct vt_device *vd, const term_rect_t *area) for (col = area->tr_begin.tp_col; col < area->tr_end.tp_col; ++col) { z = row * PIXEL_WIDTH(VT_FB_MAX_WIDTH) + col; + if (z >= PIXEL_HEIGHT(VT_FB_MAX_HEIGHT) * + PIXEL_WIDTH(VT_FB_MAX_WIDTH)) + continue; if (vd->vd_drawn) vd->vd_drawn[z] = 0; if (vd->vd_drawnfg) diff --git a/sys/dev/vt/hw/vga/vt_vga.c b/sys/dev/vt/hw/vga/vt_vga.c index 88a9b1c4733..563867399e5 100644 --- a/sys/dev/vt/hw/vga/vt_vga.c +++ b/sys/dev/vt/hw/vga/vt_vga.c @@ -888,6 +888,9 @@ vga_bitblt_text_txtmode(struct vt_device *vd, const struct vt_window *vw, &fg, &bg); z = row * PIXEL_WIDTH(VT_FB_MAX_WIDTH) + col; + if (z >= PIXEL_HEIGHT(VT_FB_MAX_HEIGHT) * + PIXEL_WIDTH(VT_FB_MAX_WIDTH)) + continue; if (vd->vd_drawn && (vd->vd_drawn[z] == c) && vd->vd_drawnfg && (vd->vd_drawnfg[z] == fg) && vd->vd_drawnbg && (vd->vd_drawnbg[z] == bg)) @@ -941,6 +944,9 @@ vga_invalidate_text(struct vt_device *vd, const term_rect_t *area) col < area->tr_end.tp_col; ++col) { z = row * PIXEL_WIDTH(VT_FB_MAX_WIDTH) + col; + if (z >= PIXEL_HEIGHT(VT_FB_MAX_HEIGHT) * + PIXEL_WIDTH(VT_FB_MAX_WIDTH)) + continue; if (vd->vd_drawn) vd->vd_drawn[z] = 0; if (vd->vd_drawnfg) -- 2.45.0