On Sunday, February 04, 2018 09:18:03 AM Peter Malone wrote: > Hi folks, Hi, > 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. I queued the patch (with Mathieu's ACK and CVE number added to the patch description) for v4.16, thanks. > On Wed, Jan 31, 2018 at 10:49 AM, Mathieu Malaterre <malat@xxxxxxxxxx> wrote: > > Hi Peter, > > > > On Wed, Jan 31, 2018 at 3:57 PM, Peter Malone <peter.malone@xxxxxxxxx> 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 <peter.malone@xxxxxxxxx> > >> --- > > > > 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 <malat@xxxxxxxxxx> Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
