I revisit the code again. You're right that the commit log is not correct. The '\0' would be read and even the one pass it.
Regards, Jian > -----Original Message----- > From: Kinney, Michael D > Sent: Thursday, December 28, 2017 12:38 AM > To: Wang, Jian J <[email protected]>; [email protected]; Kinney, > Michael D <[email protected]> > Cc: Yao, Jiewen <[email protected]>; Zeng, Star <[email protected]>; > Gao, Liming <[email protected]> > Subject: RE: [edk2] [PATCH] MdePkg/BasePrintLib: Fix incorrect Precision > position calculation > > Is the commit log correct? > > Is the issue that the character past the '\0' could be read? > > Mike > > > -----Original Message----- > > From: Wang, Jian J > > Sent: Tuesday, December 26, 2017 6:14 PM > > To: Wang, Jian J <[email protected]>; edk2- > > [email protected] > > Cc: Kinney, Michael D <[email protected]>; Yao, > > Jiewen <[email protected]>; Zeng, Star > > <[email protected]>; Gao, Liming <[email protected]> > > Subject: RE: [edk2] [PATCH] MdePkg/BasePrintLib: Fix > > incorrect Precision position calculation > > > > Mike and Liming, > > > > Could you take a look at this patch? > > > > Regards, > > Jian > > > > > > > -----Original Message----- > > > From: edk2-devel [mailto:edk2-devel- > > [email protected]] On Behalf Of Jian J > > > Wang > > > Sent: Monday, December 25, 2017 10:09 AM > > > To: [email protected] > > > Cc: Kinney, Michael D <[email protected]>; > > Yao, Jiewen > > > <[email protected]>; Zeng, Star > > <[email protected]>; Gao, Liming > > > <[email protected]> > > > Subject: [edk2] [PATCH] MdePkg/BasePrintLib: Fix > > incorrect Precision position > > > calculation > > > > > > Due to the a potential hole in the stop condition of > > for-loop, the two > > > continuous access to ArgumentString (index, index+1) > > inside the loop > > > might cause the string ending character ('\0') to be > > read. > > > > > > Cc: Michael D Kinney <[email protected]> > > > Cc: Liming Gao <[email protected]> > > > Cc: Jiewen Yao <[email protected]> > > > Cc: Star Zeng <[email protected]> > > > Contributed-under: TianoCore Contribution Agreement 1.1 > > > Signed-off-by: Jian J Wang <[email protected]> > > > --- > > > MdePkg/Library/BasePrintLib/PrintLibInternal.c | 5 > > ++++- > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > diff --git > > a/MdePkg/Library/BasePrintLib/PrintLibInternal.c > > > b/MdePkg/Library/BasePrintLib/PrintLibInternal.c > > > index 28d946472f..297d5a05b5 100644 > > > --- a/MdePkg/Library/BasePrintLib/PrintLibInternal.c > > > +++ b/MdePkg/Library/BasePrintLib/PrintLibInternal.c > > > @@ -1107,7 +1107,10 @@ BasePrintLibSPrintMarker ( > > > // Compute the number of characters in > > ArgumentString and store it in > > > Count > > > // ArgumentString is either null-terminated, or > > it contains Precision > > > characters > > > // > > > - for (Count = 0; Count < Precision || ((Flags & > > PRECISION) == 0); Count++) { > > > + for (Count = 0; > > > + ArgumentString[Count * > > BytesPerArgumentCharacter] != '\0' && > > > + (Count < Precision || ((Flags & PRECISION) > > == 0)); > > > + Count++) { > > > ArgumentCharacter = ((ArgumentString[Count * > > > BytesPerArgumentCharacter] & 0xff) | > > ((ArgumentString[Count * > > > BytesPerArgumentCharacter + 1]) << 8)) & ArgumentMask; > > > if (ArgumentCharacter == 0) { > > > break; > > > -- > > > 2.15.1.windows.2 > > > > > > _______________________________________________ > > > edk2-devel mailing list > > > [email protected] > > > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
