[edk2-devel] [PATCH] ShellPkg/Type.c: Add value check before (LoopVar - 1)
Gao, Zhichao
zhichao.gao at intel.com
Mon Jul 15 07:30:05 UTC 2019
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1964
If the file begin with single line Feed ('\n'), then
"AsciiChar == '\n' && ((CHAR8*)Buffer)[LoopVar-1] != '\r'"
would cause a underflow. Add this condition
"(AsciiChar == '\n' && LoopVar == 0)" before it to make sure
(LoopVar - 1) would never encounter a underflow.
Cc: Jaben Carsey <jaben.carsey at intel.com>
Cc: Ray Ni <ray.ni at intel.com>
Cc: Andrew Fish <afish at apple.com>
Signed-off-by: Zhichao Gao <zhichao.gao at intel.com>
---
ShellPkg/Library/UefiShellLevel3CommandsLib/Type.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/ShellPkg/Library/UefiShellLevel3CommandsLib/Type.c b/ShellPkg/Library/UefiShellLevel3CommandsLib/Type.c
index 4efc0a8e24..c1f670c713 100644
--- a/ShellPkg/Library/UefiShellLevel3CommandsLib/Type.c
+++ b/ShellPkg/Library/UefiShellLevel3CommandsLib/Type.c
@@ -78,12 +78,13 @@ TypeFileByHandle (
// Allow Line Feed (LF) (0xA) & Carriage Return (CR) (0xD)
// characters to be displayed as is.
//
- if (AsciiChar == '\n' && ((CHAR8*)Buffer)[LoopVar-1] != '\r') {
+ if ((AsciiChar == '\n' && LoopVar == 0) ||
+ (AsciiChar == '\n' && ((CHAR8*)Buffer)[LoopVar-1] != '\r')) {
//
- // In case Line Feed (0xA) is encountered & Carriage Return (0xD)
- // was not the previous character, print CR and LF. This is because
- // Shell 2.0 requires carriage return with line feed for displaying
- // each new line from left.
+ // In case file begin with single line Feed or Line Feed (0xA) is
+ // encountered & Carriage Return (0xD) was not previous character,
+ // print CR and LF. This is because Shell 2.0 requires carriage
+ // return Swith line feed for displaying each new line from left.
//
ShellPrintEx (-1, -1, L"\r\n");
continue;
--
2.21.0.windows.1
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#43711): https://edk2.groups.io/g/devel/message/43711
Mute This Topic: https://groups.io/mt/32476115/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-
More information about the edk2-devel-archive
mailing list