Re: [PATCH v2] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

, Oct 27, 2021 at 10:32 PM George Kennedy wrote: Do a sanity check on pixclock value to avoid divide by zero. If the pixclock value is zero, the cirrusfb driver will round up pixclock to get the derived frequency as close to maxclock as possible. Syzkaller reported a divide error

Re: [PATCH] drm: check drm_format_info hsub and vsub to avoid divide by zero

On 11/25/2021 10:27 AM, Daniel Vetter wrote: On Mon, Nov 22, 2021 at 10:29:05AM -0500, George Kennedy wrote: On 11/19/2021 9:25 AM, Jani Nikula wrote: On Fri, 19 Nov 2021, Daniel Vetter wrote: On Fri, Nov 19, 2021 at 12:03:00PM +0200, Ville Syrjälä wrote: On Fri, Nov 19, 2021 at 10:40

Re: [PATCH] drm: check drm_format_info hsub and vsub to avoid divide by zero

, 2021 at 08:57:17AM -0500, George Kennedy wrote: Do a sanity check on struct drm_format_info hsub and vsub values to avoid divide by zero. Syzkaller reported a divide error in framebuffer_check() when the DRM_FORMAT_Q410 or DRM_FORMAT_Q401 pixel_format is passed in via the DRM_IOCTL_MODE_ADDFB2

Re: [PATCH] drm: check drm_format_info hsub and vsub to avoid divide by zero

On 10/29/2021 10:14 AM, Brian Starkey wrote: Hi, On Fri, Oct 29, 2021 at 09:15:28AM -0400, George Kennedy wrote: Asking if you have any input on how to deal with hsub and vsub = zero? That's just a straight mistake on those formats - they should be 1. My bad for not spotting it in review

Re: [PATCH] drm: check drm_format_info hsub and vsub to avoid divide by zero

On 10/28/2021 10:04 AM, Ville Syrjälä wrote: On Thu, Oct 28, 2021 at 08:57:17AM -0500, George Kennedy wrote: Do a sanity check on struct drm_format_info hsub and vsub values to avoid divide by zero. Syzkaller reported a divide error in framebuffer_check() when the DRM_FORMAT_Q410

[PATCH] drm: check drm_format_info hsub and vsub to avoid divide by zero

ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: George Kennedy --- drivers/gpu/drm/drm_framebuffer.c | 10 ++

[PATCH v2] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

do_syscall_64+0x3a/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: George Kennedy --- drivers/video/fbdev/cirrusfb.c | 16 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/video/fbdev/cirrusfb.c b/drivers/video/fbdev/cirrusfb.c index 93802ab..3d47c34

Re: [PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

On 10/27/2021 2:53 AM, Geert Uytterhoeven wrote: Hi George, On Wed, Oct 27, 2021 at 3:13 AM George Kennedy wrote: On 10/26/2021 1:12 PM, Geert Uytterhoeven wrote: On Tue, Oct 26, 2021 at 5:48 PM George Kennedy wrote: On 10/26/2021 10:11 AM, Geert Uytterhoeven wrote: On Tue, Oct 26

Re: [PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

On 10/27/2021 2:53 AM, Geert Uytterhoeven wrote: Hi George, On Wed, Oct 27, 2021 at 3:13 AM George Kennedy wrote: On 10/26/2021 1:12 PM, Geert Uytterhoeven wrote: On Tue, Oct 26, 2021 at 5:48 PM George Kennedy wrote: On 10/26/2021 10:11 AM, Geert Uytterhoeven wrote: On Tue, Oct 26

Re: [PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

Hi Geert, On 10/26/2021 1:12 PM, Geert Uytterhoeven wrote: Hi George, On Tue, Oct 26, 2021 at 5:48 PM George Kennedy wrote: On 10/26/2021 10:11 AM, Geert Uytterhoeven wrote: On Tue, Oct 26, 2021 at 3:38 PM George Kennedy wrote: On 10/26/2021 4:30 AM, Geert Uytterhoeven wrote: On Mon, Oct

Re: [PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

Hi Geert, On 10/26/2021 10:11 AM, Geert Uytterhoeven wrote: Hi George, On Tue, Oct 26, 2021 at 3:38 PM George Kennedy wrote: On 10/26/2021 4:30 AM, Geert Uytterhoeven wrote: On Mon, Oct 25, 2021 at 9:37 PM George Kennedy wrote: On 10/25/2021 3:07 PM, Greg KH wrote: On Mon, Oct 25, 2021

Re: [PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

Hi Geert, On 10/26/2021 4:30 AM, Geert Uytterhoeven wrote: Hi George, On Mon, Oct 25, 2021 at 9:37 PM George Kennedy wrote: On 10/25/2021 3:07 PM, Greg KH wrote: On Mon, Oct 25, 2021 at 02:01:30PM -0500, George Kennedy wrote: Do a sanity check on pixclock value before using it as a divisor

Re: [PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

On 10/25/2021 3:07 PM, Greg KH wrote: On Mon, Oct 25, 2021 at 02:01:30PM -0500, George Kennedy wrote: Do a sanity check on pixclock value before using it as a divisor. Syzkaller reported a divide error in cirrusfb_check_pixclock. divide error: [#1] SMP KASAN PTI CPU: 0 PID: 14938 Comm

[PATCH] video: fbdev: cirrusfb: check pixclock to avoid divide by zero

-2 RIP: 0010:cirrusfb_check_var+0x6f1/0x1260 Call Trace: fb_set_var+0x398/0xf90 do_fb_ioctl+0x4b8/0x6f0 fb_ioctl+0xeb/0x130 __x64_sys_ioctl+0x19d/0x220 do_syscall_64+0x3a/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Signed-off-by: George Kennedy --- drivers/video/fbdev/cirrusfb.c | 3

Re: [PATCH 5.4.y 0/2] 5.4.y missing upstream commits 7beb691f and 51f644b4, causing: WARNING in vkms_vblank_simulate

request. Thank you, George On 5/31/2021 8:00 AM, Greg KH wrote: On Fri, May 21, 2021 at 03:53:18PM -0500, George Kennedy wrote: During Syzkaller reproducer testing on 5.4.y (5.4.121-rc1) the following warning occurred: WARNING in vkms_vblank_simulate https://syzkaller.appspot.com//bug?id

Re: [PATCH] fbdev: Detect integer underflow at "struct fbcon_ops"->clear_margins.

Hello Tetsuo, Can you try the a.out built from the original Syzkaller modified repro C program? It walks 0-7 through xres and yres of the fb_var_screeninfo struct. // https://syzkaller.appspot.com/bug?id=a565882df74fa76f10d3a6fec4be31098dbb37c6 // autogenerated by syzkaller