| Message ID | 20220202235811.1621017-1-yzhai003@ucr.edu (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
| Series | [v6] fbdev: fbmem: Fix the implicit type casting | expand |
Hi Daniel, I assume you will take this. Patch is: Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Sam On Wed, Feb 02, 2022 at 03:58:08PM -0800, Yizhuo Zhai wrote: > In function do_fb_ioctl(), the "arg" is the type of unsigned long, > and in "case FBIOBLANK:" this argument is casted into an int before > passig to fb_blank(). In fb_blank(), the comparision > if (blank > FB_BLANK_POWERDOWN) would be bypass if the original > "arg" is a large number, which is possible because it comes from > the user input. Fix this by adding the check before the function > call. > > Signed-off-by: Yizhuo Zhai <yzhai003@ucr.edu> > --- > drivers/video/fbdev/core/fbmem.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c > index 0fa7ede94fa6..13083ad8d751 100644 > --- a/drivers/video/fbdev/core/fbmem.c > +++ b/drivers/video/fbdev/core/fbmem.c > @@ -1160,6 +1160,8 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, > ret = fbcon_set_con2fb_map_ioctl(argp); > break; > case FBIOBLANK: > + if (arg > FB_BLANK_POWERDOWN) > + return -EINVAL; > console_lock(); > lock_fb_info(info); > ret = fb_blank(info, arg); > -- > 2.25.1
On 2/3/22 07:39, Sam Ravnborg wrote: > Hi Daniel, > > I assume you will take this. > > Patch is: > Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Helge Deller <deller@gmx.de> Helge > > Sam > > On Wed, Feb 02, 2022 at 03:58:08PM -0800, Yizhuo Zhai wrote: >> In function do_fb_ioctl(), the "arg" is the type of unsigned long, >> and in "case FBIOBLANK:" this argument is casted into an int before >> passig to fb_blank(). In fb_blank(), the comparision >> if (blank > FB_BLANK_POWERDOWN) would be bypass if the original >> "arg" is a large number, which is possible because it comes from >> the user input. Fix this by adding the check before the function >> call. >> >> Signed-off-by: Yizhuo Zhai <yzhai003@ucr.edu> >> --- >> drivers/video/fbdev/core/fbmem.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c >> index 0fa7ede94fa6..13083ad8d751 100644 >> --- a/drivers/video/fbdev/core/fbmem.c >> +++ b/drivers/video/fbdev/core/fbmem.c >> @@ -1160,6 +1160,8 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, >> ret = fbcon_set_con2fb_map_ioctl(argp); >> break; >> case FBIOBLANK: >> + if (arg > FB_BLANK_POWERDOWN) >> + return -EINVAL; >> console_lock(); >> lock_fb_info(info); >> ret = fb_blank(info, arg); >> -- >> 2.25.1
On Thu, Feb 03, 2022 at 09:18:30AM +0100, Helge Deller wrote: > On 2/3/22 07:39, Sam Ravnborg wrote: > > Hi Daniel, > > > > I assume you will take this. > > > > Patch is: > > Reviewed-by: Sam Ravnborg <sam@ravnborg.org> > > > Acked-by: Helge Deller <deller@gmx.de> Pushed to drm-misc-fixes, thanks for patch&review. -Daniel > > Helge > > > > > Sam > > > > On Wed, Feb 02, 2022 at 03:58:08PM -0800, Yizhuo Zhai wrote: > >> In function do_fb_ioctl(), the "arg" is the type of unsigned long, > >> and in "case FBIOBLANK:" this argument is casted into an int before > >> passig to fb_blank(). In fb_blank(), the comparision > >> if (blank > FB_BLANK_POWERDOWN) would be bypass if the original > >> "arg" is a large number, which is possible because it comes from > >> the user input. Fix this by adding the check before the function > >> call. > >> > >> Signed-off-by: Yizhuo Zhai <yzhai003@ucr.edu> > >> --- > >> drivers/video/fbdev/core/fbmem.c | 2 ++ > >> 1 file changed, 2 insertions(+) > >> > >> diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c > >> index 0fa7ede94fa6..13083ad8d751 100644 > >> --- a/drivers/video/fbdev/core/fbmem.c > >> +++ b/drivers/video/fbdev/core/fbmem.c > >> @@ -1160,6 +1160,8 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, > >> ret = fbcon_set_con2fb_map_ioctl(argp); > >> break; > >> case FBIOBLANK: > >> + if (arg > FB_BLANK_POWERDOWN) > >> + return -EINVAL; > >> console_lock(); > >> lock_fb_info(info); > >> ret = fb_blank(info, arg); > >> -- > >> 2.25.1 >
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 0fa7ede94fa6..13083ad8d751 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1160,6 +1160,8 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, ret = fbcon_set_con2fb_map_ioctl(argp); break; case FBIOBLANK: + if (arg > FB_BLANK_POWERDOWN) + return -EINVAL; console_lock(); lock_fb_info(info); ret = fb_blank(info, arg);
In function do_fb_ioctl(), the "arg" is the type of unsigned long, and in "case FBIOBLANK:" this argument is casted into an int before passig to fb_blank(). In fb_blank(), the comparision if (blank > FB_BLANK_POWERDOWN) would be bypass if the original "arg" is a large number, which is possible because it comes from the user input. Fix this by adding the check before the function call. Signed-off-by: Yizhuo Zhai <yzhai003@ucr.edu> --- drivers/video/fbdev/core/fbmem.c | 2 ++ 1 file changed, 2 insertions(+)