From 7ffa9c616d41956d84b82e3c9792fd87e3d3e1ae Mon Sep 17 00:00:00 2001 From: Ryan Harkin Date: Wed, 12 Mar 2014 17:24:48 +0000 Subject: [PATCH] ArmPlatformPkg/Bds: stop inputting more characters when string is full If EditHIInputStr() is called, say with a MaxCmdLine of 2, the user is currently allowed to enter 2 characters. If the second character is a carriage return/line feed, this is substituted with a NULL and the function returns. If the second character is a regular character, the loop terminated and the function returns. However, the buffer has not been NULL terminated. This patch prevents the user from entering a regular character as the final character and ensures that the only way out of the input is by pressing ESC or ENTER (or equivalent). Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ryan Harkin Reviewed-by: Olivier Martin git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15325 6f19259b-4bc3-4df7-8a09-765794883524 --- ArmPlatformPkg/Bds/BdsHelper.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/ArmPlatformPkg/Bds/BdsHelper.c b/ArmPlatformPkg/Bds/BdsHelper.c index 3142d85c10..1c233d76c5 100644 --- a/ArmPlatformPkg/Bds/BdsHelper.c +++ b/ArmPlatformPkg/Bds/BdsHelper.c @@ -35,7 +35,7 @@ EditHIInputStr ( Print (CmdLine); // To prevent a buffer overflow, we only allow to enter (MaxCmdLine-1) characters - for (CmdLineIndex = StrLen (CmdLine); CmdLineIndex < MaxCmdLine - 1; ) { + for (CmdLineIndex = StrLen (CmdLine); CmdLineIndex < MaxCmdLine; ) { Status = gBS->WaitForEvent (1, &gST->ConIn->WaitForKey, &WaitIndex); ASSERT_EFI_ERROR (Status); @@ -62,7 +62,7 @@ EditHIInputStr ( } } else if ((Key.ScanCode == SCAN_ESC) || (Char == 0x1B) || (Char == 0x0)) { return EFI_INVALID_PARAMETER; - } else { + } else if (CmdLineIndex < (MaxCmdLine-1)) { CmdLine[CmdLineIndex++] = Key.UnicodeChar; Print (L"%c", Key.UnicodeChar); } @@ -187,9 +187,7 @@ GetHIInputBoolean ( while(1) { Print (L"[y/n] "); - // Set MaxCmdLine to 3 to give space for carriage return (when the user - // hits enter) and terminal '\0'. - Status = GetHIInputStr (CmdBoolean, 3); + Status = GetHIInputStr (CmdBoolean, 2); if (EFI_ERROR(Status)) { return Status; } else if ((CmdBoolean[0] == L'y') || (CmdBoolean[0] == L'Y')) { -- 2.39.2