Re: [PATCH v2] Fixing arbitrary kernel leak in case FBIOGETCMAP_SPARC in sbusfb_ioctl_helper().
Hi folks, CVE-2018-6412 has been created for this. Is it possible for you to add a note indicating the CVE number when merging the patch? I received the CVE number after the patch was created and ack'd, which is why I didn't include it in the commit message. On Jan 31, 2018 10:49, "Mathieu Malaterre" wrote: > Hi Peter, > > On Wed, Jan 31, 2018 at 3:57 PM, Peter Malone > wrote: > > Fixing arbitrary kernel leak in case FBIOGETCMAP_SPARC in > > sbusfb_ioctl_helper(). > > > > 'index' is defined as an int in sbusfb_ioctl_helper(). > > We retrieve this from the user: > > if (get_user(index, &c->index) || > > __get_user(count, &c->count) || > > __get_user(ured, &c->red) || > > __get_user(ugreen, &c->green) || > > __get_user(ublue, &c->blue)) > >return -EFAULT; > > > > and then we use 'index' in the following way: > > red = cmap->red[index + i] >> 8; > > green = cmap->green[index + i] >> 8; > > blue = cmap->blue[index + i] >> 8; > > > > This is a classic information leak vulnerability. 'index' should be > > an unsigned int, given its usage above. > > > > This patch is straight-forward; it changes 'index' to unsigned int > > in two switch-cases: FBIOGETCMAP_SPARC && FBIOPUTCMAP_SPARC. > > > > Signed-off-by: Peter Malone > > --- > > much better :) > > > v2: fixed formatting > > > > drivers/video/fbdev/sbuslib.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/video/fbdev/sbuslib.c > b/drivers/video/fbdev/sbuslib.c > > index af6fc97f4ba4..a436d44f1b7f 100644 > > --- a/drivers/video/fbdev/sbuslib.c > > +++ b/drivers/video/fbdev/sbuslib.c > > @@ -122,7 +122,7 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned > long arg, > > unsigned char __user *ured; > > unsigned char __user *ugreen; > > unsigned char __user *ublue; > > - int index, count, i; > > + unsigned int index, count, i; > > > > if (get_user(index, &c->index) || > > __get_user(count, &c->count) || > > @@ -161,7 +161,7 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned > long arg, > > unsigned char __user *ugreen; > > unsigned char __user *ublue; > > struct fb_cmap *cmap = &info->cmap; > > - int index, count, i; > > + unsigned int index, count, i; > > u8 red, green, blue; > > > > if (get_user(index, &c->index) || > > -- > > 2.14.3 > > > > By just looking at the code and commit message: > > Acked-by: Mathieu Malaterre > ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: [PATCH v2] Fixing arbitrary kernel leak in case FBIOGETCMAP_SPARC in sbusfb_ioctl_helper().
Hi folks, CVE-2018-6412 has been created for this. Is it possible for you to add a note indicating the CVE number when merging the patch? I received the CVE number after the patch was created and ack'd, which is why I didn't include it in the commit message. On Wed, Jan 31, 2018 at 10:49 AM, Mathieu Malaterre wrote: > Hi Peter, > > On Wed, Jan 31, 2018 at 3:57 PM, Peter Malone wrote: >> Fixing arbitrary kernel leak in case FBIOGETCMAP_SPARC in >> sbusfb_ioctl_helper(). >> >> 'index' is defined as an int in sbusfb_ioctl_helper(). >> We retrieve this from the user: >> if (get_user(index, &c->index) || >> __get_user(count, &c->count) || >> __get_user(ured, &c->red) || >> __get_user(ugreen, &c->green) || >> __get_user(ublue, &c->blue)) >>return -EFAULT; >> >> and then we use 'index' in the following way: >> red = cmap->red[index + i] >> 8; >> green = cmap->green[index + i] >> 8; >> blue = cmap->blue[index + i] >> 8; >> >> This is a classic information leak vulnerability. 'index' should be >> an unsigned int, given its usage above. >> >> This patch is straight-forward; it changes 'index' to unsigned int >> in two switch-cases: FBIOGETCMAP_SPARC && FBIOPUTCMAP_SPARC. >> >> Signed-off-by: Peter Malone >> --- > > much better :) > >> v2: fixed formatting >> >> drivers/video/fbdev/sbuslib.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/video/fbdev/sbuslib.c b/drivers/video/fbdev/sbuslib.c >> index af6fc97f4ba4..a436d44f1b7f 100644 >> --- a/drivers/video/fbdev/sbuslib.c >> +++ b/drivers/video/fbdev/sbuslib.c >> @@ -122,7 +122,7 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long >> arg, >> unsigned char __user *ured; >> unsigned char __user *ugreen; >> unsigned char __user *ublue; >> - int index, count, i; >> + unsigned int index, count, i; >> >> if (get_user(index, &c->index) || >> __get_user(count, &c->count) || >> @@ -161,7 +161,7 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long >> arg, >> unsigned char __user *ugreen; >> unsigned char __user *ublue; >> struct fb_cmap *cmap = &info->cmap; >> - int index, count, i; >> + unsigned int index, count, i; >> u8 red, green, blue; >> >> if (get_user(index, &c->index) || >> -- >> 2.14.3 >> > > By just looking at the code and commit message: > > Acked-by: Mathieu Malaterre -- Regards, Peter. ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
