summaryrefslogtreecommitdiffstats
path: root/NetworkPkg
diff options
context:
space:
mode:
authorLaszlo Ersek <lersek@redhat.com>2021-06-08 14:12:54 +0200
committermergify[bot] <37929162+mergify[bot]@users.noreply.github.com>2021-06-09 17:25:03 +0000
commitcf01b2dc8fc3ff9cf49fb891af5703dc03e3193e (patch)
treef529a3d7933afad2cfc7ba578a0f98f32c6e97b2 /NetworkPkg
parente8f28b09e63dfdbb4169969a43c65f86c44b035a (diff)
downloadedk2-cf01b2dc8fc3ff9cf49fb891af5703dc03e3193e.tar.gz
edk2-cf01b2dc8fc3ff9cf49fb891af5703dc03e3193e.tar.bz2
edk2-cf01b2dc8fc3ff9cf49fb891af5703dc03e3193e.zip
NetworkPkg/IScsiDxe: fix potential integer overflow in IScsiBinToHex()
Considering IScsiBinToHex(): > if (((*HexLength) - 3) < BinLength * 2) { > *HexLength = BinLength * 2 + 3; > } the following subexpressions are problematic: (*HexLength) - 3 BinLength * 2 BinLength * 2 + 3 The first one may wrap under zero, the latter two may wrap over MAX_UINT32. Rewrite the calculation using SafeIntLib. While at it, change the type of the "Index" variable from UINTN to UINT32. The largest "Index"-based value that we calculate is Index * 2 + 2 (with (Index == BinLength)) Because the patch makes BinLength * 2 + 3 safe to calculate in UINT32, using UINT32 for Index * 2 + 2 (with (Index == BinLength)) is safe too. Consistently using UINT32 improves readability. This patch is best reviewed with "git show -W". The integer overflows that this patch fixes are theoretical; a subsequent patch in the series will audit the IScsiBinToHex() call sites, and show that none of them can fail. Cc: Jiaxin Wu <jiaxin.wu@intel.com> Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com> Cc: Philippe Mathieu-Daudé <philmd@redhat.com> Cc: Siyuan Fu <siyuan.fu@intel.com> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3356 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20210608121259.32451-6-lersek@redhat.com>
Diffstat (limited to 'NetworkPkg')
-rw-r--r--NetworkPkg/IScsiDxe/IScsiDxe.inf1
-rw-r--r--NetworkPkg/IScsiDxe/IScsiImpl.h1
-rw-r--r--NetworkPkg/IScsiDxe/IScsiMisc.c19
-rw-r--r--NetworkPkg/IScsiDxe/IScsiMisc.h1
4 files changed, 18 insertions, 4 deletions
diff --git a/NetworkPkg/IScsiDxe/IScsiDxe.inf b/NetworkPkg/IScsiDxe/IScsiDxe.inf
index 543c408302..1dde56d00c 100644
--- a/NetworkPkg/IScsiDxe/IScsiDxe.inf
+++ b/NetworkPkg/IScsiDxe/IScsiDxe.inf
@@ -74,6 +74,7 @@
MemoryAllocationLib
NetLib
PrintLib
+ SafeIntLib
TcpIoLib
UefiBootServicesTableLib
UefiDriverEntryPoint
diff --git a/NetworkPkg/IScsiDxe/IScsiImpl.h b/NetworkPkg/IScsiDxe/IScsiImpl.h
index d895c7feb9..ac3a25730e 100644
--- a/NetworkPkg/IScsiDxe/IScsiImpl.h
+++ b/NetworkPkg/IScsiDxe/IScsiImpl.h
@@ -44,6 +44,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
#include <Library/MemoryAllocationLib.h>
#include <Library/NetLib.h>
#include <Library/PrintLib.h>
+#include <Library/SafeIntLib.h>
#include <Library/TcpIoLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiHiiServicesLib.h>
diff --git a/NetworkPkg/IScsiDxe/IScsiMisc.c b/NetworkPkg/IScsiDxe/IScsiMisc.c
index b8fef3ff6f..42988e15cb 100644
--- a/NetworkPkg/IScsiDxe/IScsiMisc.c
+++ b/NetworkPkg/IScsiDxe/IScsiMisc.c
@@ -316,6 +316,7 @@ IScsiMacAddrToStr (
@retval EFI_SUCCESS The binary data is converted to the hexadecimal string
and the length of the string is updated.
@retval EFI_BUFFER_TOO_SMALL The string is too small.
+ @retval EFI_BAD_BUFFER_SIZE BinLength is too large for hex encoding.
@retval EFI_INVALID_PARAMETER The IP string is malformatted.
**/
@@ -327,18 +328,28 @@ IScsiBinToHex (
IN OUT UINT32 *HexLength
)
{
- UINTN Index;
+ UINT32 HexLengthMin;
+ UINT32 HexLengthProvided;
+ UINT32 Index;
if ((HexStr == NULL) || (BinBuffer == NULL) || (BinLength == 0)) {
return EFI_INVALID_PARAMETER;
}
- if (((*HexLength) - 3) < BinLength * 2) {
- *HexLength = BinLength * 2 + 3;
+ //
+ // Safely calculate: HexLengthMin := BinLength * 2 + 3.
+ //
+ if (RETURN_ERROR (SafeUint32Mult (BinLength, 2, &HexLengthMin)) ||
+ RETURN_ERROR (SafeUint32Add (HexLengthMin, 3, &HexLengthMin))) {
+ return EFI_BAD_BUFFER_SIZE;
+ }
+
+ HexLengthProvided = *HexLength;
+ *HexLength = HexLengthMin;
+ if (HexLengthProvided < HexLengthMin) {
return EFI_BUFFER_TOO_SMALL;
}
- *HexLength = BinLength * 2 + 3;
//
// Prefix for Hex String.
//
diff --git a/NetworkPkg/IScsiDxe/IScsiMisc.h b/NetworkPkg/IScsiDxe/IScsiMisc.h
index 46c725aab3..231413993b 100644
--- a/NetworkPkg/IScsiDxe/IScsiMisc.h
+++ b/NetworkPkg/IScsiDxe/IScsiMisc.h
@@ -150,6 +150,7 @@ IScsiAsciiStrToIp (
@retval EFI_SUCCESS The binary data is converted to the hexadecimal string
and the length of the string is updated.
@retval EFI_BUFFER_TOO_SMALL The string is too small.
+ @retval EFI_BAD_BUFFER_SIZE BinLength is too large for hex encoding.
@retval EFI_INVALID_PARAMETER The IP string is malformatted.
**/