mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-05 00:20:32 +00:00
Code Issues Releases Wiki Activity

video: fbdev: kyro: fix a DoS bug by restricting user input

Browse source 
The user can pass in any value to the driver through the 'ioctl'
interface. The driver dost not check, which may cause DoS bugs.

The following log reveals it:

divide error: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:SetOverlayViewPort+0x133/0x5f0 drivers/video/fbdev/kyro/STG4000OverlayDevice.c:476
Call Trace:
 kyro_dev_overlay_viewport_set drivers/video/fbdev/kyro/fbdev.c:378 [inline]
 kyrofb_ioctl+0x2eb/0x330 drivers/video/fbdev/kyro/fbdev.c:603
 do_fb_ioctl+0x1f3/0x700 drivers/video/fbdev/core/fbmem.c:1171
 fb_ioctl+0xeb/0x130 drivers/video/fbdev/core/fbmem.c:1185
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x19b/0x220 fs/ioctl.c:739
 do_syscall_64+0x32/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1626235762-2590-1-git-send-email-zheyuma97@gmail.com
This commit is contained in:
Zheyu Ma 2021-07-14 04:09:22 +00:00 committed by Sam Ravnborg
parent 5cc4e71f01
commit 98a6543917
1 changed files with 5 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
drivers/video/fbdev/kyro/fbdev.c
View file

@ -372,6 +372,11 @@ static int kyro_dev_overlay_viewport_set(u32 x, u32 y, u32 ulWidth, u32 ulHeight
/* probably haven't called CreateOverlay yet */
return -EINVAL;
if (ulWidth == 0 || ulWidth == 0xffffffff ||
ulHeight == 0 || ulHeight == 0xffffffff ||
(x < 2 && ulWidth + 2 == 0))
return -EINVAL;
/* Stop Ramdac Output */
DisableRamdacOutput(deviceInfo.pSTGReg);