syzbot has reported an issue in the framebuffer layer, where a malicious
user may overflow our built-in font data buffers.
In order to perform a reliable range check, subsystems need to know
`FONTDATAMAX` for each built-in font. Unfortunately, our font descriptor,
`struct console_font` does not contain `FONTDATAMAX`, and is part of the
UAPI, making it infeasible to modify it.
For user-provided fonts, the framebuffer layer resolves this issue by
reserving four extra words at the beginning of data buffers. Later,
whenever a function needs to access them, it simply uses the following
macros:
Recently we have gathered all the above macros to <linux/font.h>. Let us
do the same thing for built-in fonts, prepend four extra words (including
`FONTDATAMAX`) to their data buffers, so that subsystems can use these
macros for all fonts, no matter built-in or user-provided.
This patch depends on patch "fbdev, newport_con: Move FONT_EXTRA_WORDS
macros into linux/font.h".
Cc: stable@vger.kernel.org
Link: https://syzkaller.appspot.com/bug?id=08b8be45afea11888776f897895aef9ad1c3ecfd
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/ef18af00c35fb3cc826048a5f70924ed6ddce95b.1600953813.git.yepeilin.cs@gmail.com
drivers/video/console/newport_con.c is borrowing FONT_EXTRA_WORDS macros
from drivers/video/fbdev/core/fbcon.h. To keep things simple, move all
definitions into <linux/font.h>.
Since newport_con now uses four extra words, initialize the fourth word in
newport_set_font() properly.
Cc: stable@vger.kernel.org
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/7fb8bc9b0abc676ada6b7ac0e0bd443499357267.1600953813.git.yepeilin.cs@gmail.com
This patch adds an option to compile-in a high resolution
and large Terminus (ter16x32) bitmap console font for use with
HiDPI and Retina screens.
The font was convereted from standard Terminus ter-i32b.psf
(size 16x32) with the help of psftools and minor hand editing
deleting useless characters.
This patch is non-intrusive, no options are enabled by default so most
users won't notice a thing.
I am placing my changes under the GPL 2.0 just as source Terminus font.
Signed-off-by: Amanoel Dawod <amanoeladawod@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This font is suitable for framebuffer consoles on devices with a
320x240 screen, to get a reasonable number of characters (53x24) that
are still at a readable size.
The font is derived from the existing 6x11 font, but gets 3 extra
lines without sacrificing readability. Also I redesigned a some glyhps
so they are more distinct and better fill the available space.
Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
fbcon_set_font() will now check if the new font dimensions can be drawn by the
driver (by checking pixmap.blit_x and blit_y). Similarly, add 2 new
parameters to get_default_font(), font_w and font_h, to further aid in the
font selection process.
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I converted the "rl" console font from the kbd utility to be a built-in font
for the framebuffer console, and I was wondering if you would be OK with
including it. I've generated a font_rl.c file and related minor
modifications. I find it's the most visually appealing of the kbd fonts which
is why I use it and selected it for conversion. I believe the font is GPL'd.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
const-ify the font control structures and data, to make somewhat better
guarantees that these are not modified anywhere in the kernel.
Specifically for a kernel debugger to share this information from the
normal kernel code, such a guarantee seems rather desirable.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: "Antonino A. Daplas" <adaplas@hotpop.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Improve the fonts for use with the framebuffer.
I've added all the characters marked 'FIXME' in the sun12x22 font and
created a 10x18 font (based on the sun12x22 font) and a 7x14 font (based
on the vga8x16 font).
This patch is non-intrusive, no options are enabled by default so most
users won't notice a thing.
I am placing my changes under the GPL, however, I've not seen any copyright
notices on the sun12x22 font and the vga8x16 font which I derived my new
fonts from so I don't know what the copyright status is.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Peilin Ye