Ping? regards, dan carpenter On Fri, Jul 03, 2015 at 11:53:03AM +0300, Dan Carpenter wrote: > These are signed values the come from the user, we put a cap on the > upper bounds but not on the lower bounds. > > We use "karg.dataSgeOffset" to calculate "sz". We verify "sz" and > proceed as if that means that "karg.dataSgeOffset" is correct but this > fails to consider that the "sz" calculations can have integer overflows. > > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > --- > During my QC process, I realized that I sent a similar patch last year, > but never received a response. > > http://permalink.gmane.org/gmane.linux.kernel.janitors/32590 > > Looking at both of them, I guess I prefer today's patch because it is > simpler. > > diff --git a/drivers/message/fusion/mptctl.c b/drivers/message/fusion/mptctl.c > index 70bb753..fc73937 100644 > --- a/drivers/message/fusion/mptctl.c > +++ b/drivers/message/fusion/mptctl.c > @@ -1859,6 +1859,15 @@ mptctl_do_mpt_command (struct mpt_ioctl_command karg, void __user *mfPtr) > } > spin_unlock_irqrestore(&ioc->taskmgmt_lock, flags); > > + /* Basic sanity checks to prevent underflows or integer overflows */ > + if (karg.maxReplyBytes < 0 || > + karg.dataInSize < 0 || > + karg.dataOutSize < 0 || > + karg.dataSgeOffset < 0 || > + karg.maxSenseBytes < 0 || > + karg.dataSgeOffset > ioc->req_sz / 4) > + return -EINVAL; > + > /* Verify that the final request frame will not be too large. > */ > sz = karg.dataSgeOffset * 4; -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
