fbdev: controlfb: Add missing modes to fix out of bounds access

[ Upstream commit ac831a379d ]

Dan's static analysis says:

    drivers/video/fbdev/controlfb.c:560 control_setup()
    error: buffer overflow 'control_mac_modes' 20 <= 21

Indeed, control_mac_modes[] has only 20 elements, while VMODE_MAX is 22,
which may lead to an out of bounds read when parsing vmode commandline
options.

The bug was introduced in v2.4.5.6, when 2 new modes were added to
macmodes.h, but control_mac_modes[] wasn't updated:

https://kernel.opensuse.org/cgit/kernel/diff/include/video/macmodes.h?h=v2.5.2&id=29f279c764808560eaceb88fef36cbc35c529aad

Augment control_mac_modes[] with the two new video modes to fix this.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Geert Uytterhoeven 2017-11-09 18:09:33 +01:00 committed by Greg Kroah-Hartman
parent 71307dd192
commit f9a40df232

View file

@ -141,5 +141,7 @@ static struct max_cmodes control_mac_modes[] = {
{{ 1, 2}}, /* 1152x870, 75Hz */
{{ 0, 1}}, /* 1280x960, 75Hz */
{{ 0, 1}}, /* 1280x1024, 75Hz */
{{ 1, 2}}, /* 1152x768, 60Hz */
{{ 0, 1}}, /* 1600x1024, 60Hz */
};