diff options
Diffstat (limited to '0015-fbdev-fb_pm2fb-Avoid-potential-divide-by-zero-error.patch')
| -rw-r--r-- | 0015-fbdev-fb_pm2fb-Avoid-potential-divide-by-zero-error.patch | 50 |
1 files changed, 0 insertions, 50 deletions
diff --git a/0015-fbdev-fb_pm2fb-Avoid-potential-divide-by-zero-error.patch b/0015-fbdev-fb_pm2fb-Avoid-potential-divide-by-zero-error.patch deleted file mode 100644 index 0b6da2f4f43e..000000000000 --- a/0015-fbdev-fb_pm2fb-Avoid-potential-divide-by-zero-error.patch +++ /dev/null @@ -1,50 +0,0 @@ -From cb4bb011a683532841344ca7f281b5e04389b4f8 Mon Sep 17 00:00:00 2001 -From: Letu Ren <fantasquex@gmail.com> -Date: Thu, 18 Aug 2022 18:44:24 +0800 -Subject: [PATCH 15/73] fbdev: fb_pm2fb: Avoid potential divide by zero error - -commit 19f953e7435644b81332dd632ba1b2d80b1e37af upstream. - -In `do_fb_ioctl()` of fbmem.c, if cmd is FBIOPUT_VSCREENINFO, var will be -copied from user, then go through `fb_set_var()` and -`info->fbops->fb_check_var()` which could may be `pm2fb_check_var()`. -Along the path, `var->pixclock` won't be modified. This function checks -whether reciprocal of `var->pixclock` is too high. If `var->pixclock` is -zero, there will be a divide by zero error. So, it is necessary to check -whether denominator is zero to avoid crash. As this bug is found by -Syzkaller, logs are listed below. - -divide error in pm2fb_check_var -Call Trace: - <TASK> - fb_set_var+0x367/0xeb0 drivers/video/fbdev/core/fbmem.c:1015 - do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1110 - fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1189 - -Reported-by: Zheyu Ma <zheyuma97@gmail.com> -Signed-off-by: Letu Ren <fantasquex@gmail.com> -Signed-off-by: Helge Deller <deller@gmx.de> -Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> ---- - drivers/video/fbdev/pm2fb.c | 5 +++++ - 1 file changed, 5 insertions(+) - -diff --git a/drivers/video/fbdev/pm2fb.c b/drivers/video/fbdev/pm2fb.c -index d3be2c64f1c0..8fd79deb1e2a 100644 ---- a/drivers/video/fbdev/pm2fb.c -+++ b/drivers/video/fbdev/pm2fb.c -@@ -617,6 +617,11 @@ static int pm2fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) - return -EINVAL; - } - -+ if (!var->pixclock) { -+ DPRINTK("pixclock is zero\n"); -+ return -EINVAL; -+ } -+ - if (PICOS2KHZ(var->pixclock) > PM2_MAX_PIXCLOCK) { - DPRINTK("pixclock too high (%ldKHz)\n", - PICOS2KHZ(var->pixclock)); --- -2.37.3 - |