On Tue, Jul 20, 2021 at 2:50 AM Sam Ravnborg sam@ravnborg.org wrote:
Hi Zheyu, On Wed, Jul 14, 2021 at 04:09:22AM +0000, Zheyu Ma wrote:
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
Changes in v2: - Validate the inputs on a higher level
Much better, thanks. When a line is continued like here the statement shall aling with the opening brace. I fixed it up when applying the patch to drm-misc-next so no need to do anything this time.
Thanks for your kind reminder, I will pay attention next time.
Regards, Zheyu Ma