diff options
| author | Sergey Shtylyov <s.shtylyov@omp.ru> | 2025-05-14 23:35:58 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-06-19 15:32:03 +0200 |
| commit | b235393b9f43ff86a38ca2bde6372312ea215dc5 (patch) | |
| tree | e57dc90195704b03dba06a120718e2c21123207d | |
| parent | f697ef117ecbf3a367dfc559a6a3589905956530 (diff) | |
fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod()
[ Upstream commit 3f6dae09fc8c306eb70fdfef70726e1f154e173a ]
In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000,
cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's
then passed to fb_cvt_hperiod(), where it's used as a divider -- division
by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to
avoid such overflow...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
Fixes: 96fe6a2109db ("[PATCH] fbdev: Add VESA Coordinated Video Timings (CVT) support")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/video/fbdev/core/fbcvt.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/video/fbdev/core/fbcvt.c b/drivers/video/fbdev/core/fbcvt.c index 64843464c661..cd3821bd82e5 100644 --- a/drivers/video/fbdev/core/fbcvt.c +++ b/drivers/video/fbdev/core/fbcvt.c @@ -312,7 +312,7 @@ int fb_find_mode_cvt(struct fb_videomode *mode, int margins, int rb) cvt.f_refresh = cvt.refresh; cvt.interlace = 1; - if (!cvt.xres || !cvt.yres || !cvt.refresh) { + if (!cvt.xres || !cvt.yres || !cvt.refresh || cvt.f_refresh > INT_MAX) { printk(KERN_INFO "fbcvt: Invalid input parameters\n"); return 1; } |