On Thu, Aug 24, 2023 at 12:36:30PM +0530, coolrrsh@xxxxxxxxx wrote: > From: Rajeshwar R Shinde <coolrrsh@xxxxxxxxx> > > Syzkaller reported the following issue: > > UBSAN: shift-out-of-bounds in drivers/media/usb/gspca/cpia1.c:1031:27 > shift exponent 245 is too large for 32-bit type 'int' > > shift-out-of-bounds error was triggered when variable > 'sd->params.exposure.gain' is greater than the number of bits of int. > When the variable 'currentexp' is left shifted beyond 31 bits then > the error is produced. Therefore added the conditional expression to > verify valid range. > > Tested via syzbot. > > Reported-by: syzbot+e27f3dbdab04e43b9f73@xxxxxxxxxxxxxxxxxxxxxxxxx > Closes: https://lore.kernel.org/all/20230818164522.12806-1-coolrrsh@xxxxxxxxx > > Link: https://syzkaller.appspot.com/bug?extid=e27f3dbdab04e43b9f73 > > Signed-off-by: Rajeshwar R Shinde <coolrrsh@xxxxxxxxx> Please do not have blank lines beween these tags. You also have trailing whitespace in your changelog text :( > --- > v1->v2 > changed the patch > changed commit message and tested with checkpatch > > --- > drivers/media/usb/gspca/cpia1.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/media/usb/gspca/cpia1.c b/drivers/media/usb/gspca/cpia1.c > index 46ed95483e22..dafc522d5e7b 100644 > --- a/drivers/media/usb/gspca/cpia1.c > +++ b/drivers/media/usb/gspca/cpia1.c > @@ -1028,6 +1028,8 @@ static int set_flicker(struct gspca_dev *gspca_dev, int on, int apply) > sd->params.exposure.expMode = 2; > sd->exposure_status = EXPOSURE_NORMAL; > } > + if (sd->params.exposure.gain > 31) > + return -1; Do not make up error codes, please return a valid one and not a random negative number. Unless -1 is a valid value for this function? thanks, greg k-h
