I didn't mean a 400 static, I meant start by allocating 400 and simplify the end of the function...
> -----Original Message----- > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of > Witt, Sebastian > Sent: Tuesday, January 24, 2017 8:48 AM > To: Carsey, Jaben <jaben.car...@intel.com>; edk2-devel@lists.01.org > Subject: Re: [edk2] [PATCH] Fix edit on screens with more than 200 columns > Importance: High > > Only performance. But I haven't measured if there is a big difference > between static buffer and AllocateZeroPool. I wouldn't use a fixed value. > There may be a display device with more than 400 columns. Otherwise one > can always allocate the [LastCol + 1] buffer. > > -----Original Message----- > From: Carsey, Jaben [mailto:jaben.car...@intel.com] > Sent: Dienstag, 24. Januar 2017 17:27 > To: Witt, Sebastian (DF FA AS DH KHE 1); edk2-devel@lists.01.org > Cc: Carsey, Jaben > Subject: RE: [PATCH] Fix edit on screens with more than 200 columns > > Is there a reason to not just always start with allocating the 400 and then we > don't need to complicate the end to conditionally free the buffer? > > > -----Original Message----- > > From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of > > Witt, Sebastian > > Sent: Tuesday, January 24, 2017 5:14 AM > > To: edk2-devel@lists.01.org > > Subject: [edk2] [PATCH] Fix edit on screens with more than 200 columns > > Importance: High > > > > If the shell edit command is used on a screen with more than > > 200 columns, we get a buffer overflow. This increases the default > > buffer size to > > 400 columns and allocates a pool when this is not enough. > > > > Contributed-under: TianoCore Contribution Agreement 1.0 > > Signed-off-by: Sebastian Witt <sebastian.w...@siemens.com> > > > > --- > > .../UefiShellDebug1CommandsLib.c | 15 > > ++++++++++++++- > > 1 file changed, 14 insertions(+), 1 deletion(-) > > > > diff --git > > > a/ShellPkg/Library/UefiShellDebug1CommandsLib/UefiShellDebug1Comman > dsL > > i > > b.c > > > b/ShellPkg/Library/UefiShellDebug1CommandsLib/UefiShellDebug1Comman > dsL > > i > > b.c > > index 6ebf002..d81dd01 100644 > > --- > > > a/ShellPkg/Library/UefiShellDebug1CommandsLib/UefiShellDebug1Comman > dsL > > i > > b.c > > +++ > > > b/ShellPkg/Library/UefiShellDebug1CommandsLib/UefiShellDebug1Comman > d > > +++ sLib.c > > @@ -302,12 +302,21 @@ EditorClearLine ( > > IN UINTN LastRow > > ) > > { > > - CHAR16 Line[200]; > > + CHAR16 Buffer[400]; > > + CHAR16 *Line = Buffer; > > > > if (Row == 0) { > > Row = 1; > > } > > > > + // If there are more columns than our buffer can contain, allocate > > + new buffer if (LastCol >= (sizeof (Buffer) / sizeof (CHAR16))) { > > + Line = AllocateZeroPool (LastCol*(sizeof(CHAR16) + 1)); > > + if (Line == NULL) { > > + return; > > + } > > + } > > + > > // > > // prepare a blank line > > // > > @@ -326,6 +335,10 @@ EditorClearLine ( > > // print out the blank line > > // > > ShellPrintEx (0, ((INT32)Row) - 1, Line); > > + > > + // Free if allocated > > + if (Line != Buffer) > > + FreePool (Line); > > } > > > > /** > > -- > > 2.1.4 > > > > With best regards, > > Sebastian Witt > > > > Siemens AG > > Digital Factory Division > > Factory Automation > > Automation Products and Systems > > DF FA AS DH KHE 1 > > Oestliche Rheinbrueckenstr. 50 > > 76187 Karlsruhe, Germany > > Tel.: +49 721 595-5326 > > mailto:sebastian.w...@siemens.com > > > > www.siemens.com/ingenuityforlife > > > > Siemens Aktiengesellschaft: Chairman of the Supervisory Board: Gerhard > > Cromme; Managing Board: Joe Kaeser, Chairman, President and Chief > > Executive Officer; Roland Busch, Lisa Davis, Klaus Helmrich, Janina > > Kugel, Siegfried Russwurm, Ralf P. Thomas; Registered offices: Berlin > > and Munich, Germany; Commercial registries: Berlin Charlottenburg, HRB > > 12300, Munich, HRB 6684; WEEE-Reg.-No. DE 23691322 > > _______________________________________________ > > edk2-devel mailing list > > edk2-devel@lists.01.org > > https://lists.01.org/mailman/listinfo/edk2-devel > _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.01.org > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
