Tetsuo Handa 8c28051cdc fbmem: don't allow too huge resolutions ...

syzbot is reporting page fault at vga16fb_fillrect() [1], for
vga16fb_check_var() is failing to detect multiplication overflow.

  if (vxres * vyres > maxmem) {
    vyres = maxmem / vxres;
    if (vyres < yres)
      return -ENOMEM;
  }

Since no module would accept too huge resolutions where multiplication
overflow happens, let's reject in the common path.

Link: https://syzkaller.appspot.com/bug?extid=04168c8063cfdde1db5e [1]
Reported-by: syzbot <syzbot+04168c8063cfdde1db5e@syzkaller.appspotmail.com>
Debugged-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/185175d6-227a-7b55-433d-b070929b262c@i-love.sakura.ne.jp

2021-09-08 18:52:04 +02:00

..

bitblit.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00

cfbcopyarea.c

…

cfbfillrect.c

…

cfbimgblt.c

…

fb_cmdline.c

video/fbdev: refactor video= cmdline parsing

2019-02-08 19:24:47 +01:00

fb_ddc.c

…

fb_defio.c

Revert "fb_defio: Remove custom address_space_operations"

2021-06-01 17:38:40 +02:00

fb_draw.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

fb_notify.c

video: fbdev: core: Fix kernel-doc warnings in fbmon + fb_notify

2020-12-08 18:31:56 +01:00

fb_sys_fops.c

…

fbcmap.c

fbdev: zero-fill colormap in fbcmap.c

2021-04-10 11:12:08 +02:00

fbcon_ccw.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00

fbcon_cw.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00

fbcon_rotate.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00

fbcon_rotate.h

fbcon: Make fbcon a built-time depency for fbdev

2017-08-01 17:32:07 +02:00

fbcon_ud.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00

fbcon.c

tty: vt: always invoke vc->vc_sw->con_resize callback

2021-05-15 08:12:12 -07:00

fbcon.h

Merge tag 'drm-misc-fixes-2020-10-01' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

2020-10-06 12:38:28 +10:00

fbcvt.c

…

fbmem.c

fbmem: don't allow too huge resolutions

2021-09-08 18:52:04 +02:00

fbmon.c

video: fbdev: core: Fix kernel-doc warnings in fbmon + fb_notify

2020-12-08 18:31:56 +01:00

fbsysfs.c

fbmem: pull fbcon_update_vcs() out of fb_set_var()

2020-08-04 07:37:23 +02:00

Makefile

fbdev: remove object duplication in Makefile

2020-01-15 17:31:52 +01:00

modedb.c

fbdev: Ditch fb_edid_add_monspecs

2019-07-23 14:17:22 +02:00

softcursor.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00

svgalib.c

…

syscopyarea.c

…

sysfillrect.c

…

sysimgblt.c

…

tileblit.c

fbcon: Drop EXPORT_SYMBOL

2020-11-17 11:00:43 +01:00