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ovmf: Fix CVE-2023-45232, CVE-2023-45233
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CVE-2023-45232:
EDK2's Network Package is susceptible to an infinite loop vulnerability
when parsing unknown options in the Destination Options header of IPv6.
This vulnerability can be exploited by an attacker to gain unauthorized
access and potentially lead to a loss of Availability.

CVE-2023-45233:
EDK2's Network Package is susceptible to an infinite lop vulnerability
when parsing a PadN option in the Destination Options header of IPv6.
This vulnerability can be exploited by an attacker to gain unauthorized
access and potentially lead to a loss of Availability.

References:
https://nvd.nist.gov/vuln/detail/CVE-2023-45232
https://nvd.nist.gov/vuln/detail/CVE-2023-45233

Upstream-patches:
tianocore/edk2@4df0229
tianocore/edk2@c9c87f0

Signed-off-by: Soumya Sambu <[email protected]>
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SoumyaWind authored and hongxu-jia committed Dec 4, 2024
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360 changes: 360 additions & 0 deletions meta/recipes-core/ovmf/ovmf/CVE-2023-45232-CVE-2023-45233-0001.patch
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Original file line number Diff line number Diff line change
@@ -0,0 +1,360 @@
From 4df0229ef992d4f2721a8508787ebf9dc81fbd6e Mon Sep 17 00:00:00 2001
From: Doug Flick <[email protected]>
Date: Fri, 26 Jan 2024 05:54:50 +0800
Subject: [PATCH] NetworkPkg: Ip6Dxe: SECURITY PATCH CVE-2023-45232 Patch

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=4537
REF:https://bugzilla.tianocore.org/show_bug.cgi?id=4538

Bug Details:
PixieFail Bug #4
CVE-2023-45232
CVSS 7.5 : CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')

Infinite loop when parsing unknown options in the Destination Options
header

PixieFail Bug #5
CVE-2023-45233
CVSS 7.5 : CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')

Infinite loop when parsing a PadN option in the Destination Options
header

Change Overview:

Most importantly this change corrects the following incorrect math
and cleans up the code.

> // It is a PadN option
> //
> - Offset = (UINT8)(Offset + *(Option + Offset + 1) + 2);
> + OptDataLen = ((EFI_IP6_OPTION *)(Option + Offset))->Length;
> + Offset = IP6_NEXT_OPTION_OFFSET (Offset, OptDataLen);

> case Ip6OptionSkip:
> - Offset = (UINT8)(Offset + *(Option + Offset + 1));
> OptDataLen = ((EFI_IP6_OPTION *)(Option + Offset))->Length;
> Offset = IP6_NEXT_OPTION_OFFSET (Offset, OptDataLen);

Additionally, this change also corrects incorrect math where the calling
function was calculating the HDR EXT optionLen as a uint8 instead of a
uint16

> - OptionLen = (UINT8)((*Option + 1) * 8 - 2);
> + OptionLen = IP6_HDR_EXT_LEN (*Option) -
IP6_COMBINED_SIZE_OF_NEXT_HDR_AND_LEN;

Additionally this check adds additional logic to santize the incoming
data

Cc: Saloni Kasbekar <[email protected]>
Cc: Zachary Clark-williams <[email protected]>

Signed-off-by: Doug Flick [MSFT] <[email protected]>
Reviewed-by: Saloni Kasbekar <[email protected]>

CVE: CVE-2023-45232, CVE-2023-45233

Upstream-Status: Backport [https://github.com/tianocore/edk2/commit/4df0229ef992d4f2721a8508787ebf9dc81fbd6e]

Signed-off-by: Soumya Sambu <[email protected]>
---
NetworkPkg/Ip6Dxe/Ip6Nd.h | 35 ++++++++++++++++
NetworkPkg/Ip6Dxe/Ip6Option.c | 76 ++++++++++++++++++++++++++++++-----
NetworkPkg/Ip6Dxe/Ip6Option.h | 71 ++++++++++++++++++++++++++++++++
3 files changed, 171 insertions(+), 11 deletions(-)

diff --git a/NetworkPkg/Ip6Dxe/Ip6Nd.h b/NetworkPkg/Ip6Dxe/Ip6Nd.h
index 860934a167..bf64e9114e 100644
--- a/NetworkPkg/Ip6Dxe/Ip6Nd.h
+++ b/NetworkPkg/Ip6Dxe/Ip6Nd.h
@@ -56,13 +56,48 @@ VOID
VOID *Context
);

+//
+// Per RFC8200 Section 4.2
+//
+// Two of the currently-defined extension headers -- the Hop-by-Hop
+// Options header and the Destination Options header -- carry a variable
+// number of type-length-value (TLV) encoded "options", of the following
+// format:
+//
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
+// | Option Type | Opt Data Len | Option Data
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
+//
+// Option Type 8-bit identifier of the type of option.
+//
+// Opt Data Len 8-bit unsigned integer. Length of the Option
+// Data field of this option, in octets.
+//
+// Option Data Variable-length field. Option-Type-specific
+// data.
+//
typedef struct _IP6_OPTION_HEADER {
+ ///
+ /// identifier of the type of option.
+ ///
UINT8 Type;
+ ///
+ /// Length of the Option Data field of this option, in octets.
+ ///
UINT8 Length;
+ ///
+ /// Option-Type-specific data.
+ ///
} IP6_OPTION_HEADER;

STATIC_ASSERT (sizeof (IP6_OPTION_HEADER) == 2, "IP6_OPTION_HEADER is expected to be exactly 2 bytes long.");

+#define IP6_NEXT_OPTION_OFFSET(offset, length) (offset + sizeof(IP6_OPTION_HEADER) + length)
+STATIC_ASSERT (
+ IP6_NEXT_OPTION_OFFSET (0, 0) == 2,
+ "The next option is minimally the combined size of the option tag and length"
+ );
+
typedef struct _IP6_ETHE_ADDR_OPTION {
UINT8 Type;
UINT8 Length;
diff --git a/NetworkPkg/Ip6Dxe/Ip6Option.c b/NetworkPkg/Ip6Dxe/Ip6Option.c
index 8718d5d875..fd97ce116f 100644
--- a/NetworkPkg/Ip6Dxe/Ip6Option.c
+++ b/NetworkPkg/Ip6Dxe/Ip6Option.c
@@ -17,7 +17,8 @@
@param[in] IpSb The IP6 service data.
@param[in] Packet The to be validated packet.
@param[in] Option The first byte of the option.
- @param[in] OptionLen The length of the whole option.
+ @param[in] OptionLen The length of all options, expressed in byte length of octets.
+ Maximum length is 2046 bytes or ((n + 1) * 8) - 2 where n is 255.
@param[in] Pointer Identifies the octet offset within
the invoking packet where the error was detected.

@@ -31,12 +32,33 @@ Ip6IsOptionValid (
IN IP6_SERVICE *IpSb,
IN NET_BUF *Packet,
IN UINT8 *Option,
- IN UINT8 OptionLen,
+ IN UINT16 OptionLen,
IN UINT32 Pointer
)
{
- UINT8 Offset;
- UINT8 OptionType;
+ UINT16 Offset;
+ UINT8 OptionType;
+ UINT8 OptDataLen;
+
+ if (Option == NULL) {
+ ASSERT (Option != NULL);
+ return FALSE;
+ }
+
+ if ((OptionLen <= 0) || (OptionLen > IP6_MAX_EXT_DATA_LENGTH)) {
+ ASSERT (OptionLen > 0 && OptionLen <= IP6_MAX_EXT_DATA_LENGTH);
+ return FALSE;
+ }
+
+ if (Packet == NULL) {
+ ASSERT (Packet != NULL);
+ return FALSE;
+ }
+
+ if (IpSb == NULL) {
+ ASSERT (IpSb != NULL);
+ return FALSE;
+ }

Offset = 0;

@@ -54,7 +76,8 @@ Ip6IsOptionValid (
//
// It is a PadN option
//
- Offset = (UINT8)(Offset + *(Option + Offset + 1) + 2);
+ OptDataLen = ((IP6_OPTION_HEADER *)(Option + Offset))->Length;
+ Offset = IP6_NEXT_OPTION_OFFSET (Offset, OptDataLen);
break;
case Ip6OptionRouterAlert:
//
@@ -69,7 +92,8 @@ Ip6IsOptionValid (
//
switch (OptionType & Ip6OptionMask) {
case Ip6OptionSkip:
- Offset = (UINT8)(Offset + *(Option + Offset + 1));
+ OptDataLen = ((IP6_OPTION_HEADER *)(Option + Offset))->Length;
+ Offset = IP6_NEXT_OPTION_OFFSET (Offset, OptDataLen);
break;
case Ip6OptionDiscard:
return FALSE;
@@ -308,7 +332,7 @@ Ip6IsExtsValid (
UINT32 Pointer;
UINT32 Offset;
UINT8 *Option;
- UINT8 OptionLen;
+ UINT16 OptionLen;
BOOLEAN Flag;
UINT8 CountD;
UINT8 CountA;
@@ -385,6 +409,36 @@ Ip6IsExtsValid (
// Fall through
//
case IP6_DESTINATION:
+ //
+ // See https://www.rfc-editor.org/rfc/rfc2460#section-4.2 page 23
+ //
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ // | Next Header | Hdr Ext Len | |
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
+ // | |
+ // . .
+ // . Options .
+ // . .
+ // | |
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ //
+ //
+ // Next Header 8-bit selector. Identifies the type of header
+ // immediately following the Destination Options
+ // header. Uses the same values as the IPv4
+ // Protocol field [RFC-1700 et seq.].
+ //
+ // Hdr Ext Len 8-bit unsigned integer. Length of the
+ // Destination Options header in 8-octet units, not
+ // including the first 8 octets.
+ //
+ // Options Variable-length field, of length such that the
+ // complete Destination Options header is an
+ // integer multiple of 8 octets long. Contains one
+ // or more TLV-encoded options, as described in
+ // section 4.2.
+ //
+
if (*NextHeader == IP6_DESTINATION) {
CountD++;
}
@@ -398,7 +452,7 @@ Ip6IsExtsValid (

Offset++;
Option = ExtHdrs + Offset;
- OptionLen = (UINT8)((*Option + 1) * 8 - 2);
+ OptionLen = IP6_HDR_EXT_LEN (*Option) - sizeof (IP6_EXT_HDR);
Option++;
Offset++;

@@ -430,7 +484,7 @@ Ip6IsExtsValid (
//
// Ignore the routing header and proceed to process the next header.
//
- Offset = Offset + (RoutingHead->HeaderLen + 1) * 8;
+ Offset = Offset + IP6_HDR_EXT_LEN (RoutingHead->HeaderLen);

if (UnFragmentLen != NULL) {
*UnFragmentLen = Offset;
@@ -441,7 +495,7 @@ Ip6IsExtsValid (
// to the packet's source address, pointing to the unrecognized routing
// type.
//
- Pointer = Offset + 2 + sizeof (EFI_IP6_HEADER);
+ Pointer = Offset + sizeof (IP6_EXT_HDR) + sizeof (EFI_IP6_HEADER);
if ((IpSb != NULL) && (Packet != NULL) &&
!IP6_IS_MULTICAST (&Packet->Ip.Ip6->DestinationAddress))
{
@@ -527,7 +581,7 @@ Ip6IsExtsValid (
//
// RFC2402, Payload length is specified in 32-bit words, minus "2".
//
- OptionLen = (UINT8)((*Option + 2) * 4);
+ OptionLen = ((UINT16)(*Option + 2) * 4);
Offset = Offset + OptionLen;
break;

diff --git a/NetworkPkg/Ip6Dxe/Ip6Option.h b/NetworkPkg/Ip6Dxe/Ip6Option.h
index bd8e223c8a..fb07c28f5a 100644
--- a/NetworkPkg/Ip6Dxe/Ip6Option.h
+++ b/NetworkPkg/Ip6Dxe/Ip6Option.h
@@ -12,6 +12,77 @@

#define IP6_FRAGMENT_OFFSET_MASK (~0x3)

+//
+// For more information see RFC 8200, Section 4.3, 4.4, and 4.6
+//
+// This example format is from section 4.6
+// This does not apply to fragment headers
+//
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+// | Next Header | Hdr Ext Len | |
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
+// | |
+// . .
+// . Header-Specific Data .
+// . .
+// | |
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//
+// Next Header 8-bit selector. Identifies the type of
+// header immediately following the extension
+// header. Uses the same values as the IPv4
+// Protocol field [IANA-PN].
+//
+// Hdr Ext Len 8-bit unsigned integer. Length of the
+// Destination Options header in 8-octet units,
+// not including the first 8 octets.
+
+//
+// These defines apply to the following:
+// 1. Hop by Hop
+// 2. Routing
+// 3. Destination
+//
+typedef struct _IP6_EXT_HDR {
+ ///
+ /// The Next Header field identifies the type of header immediately
+ ///
+ UINT8 NextHeader;
+ ///
+ /// The Hdr Ext Len field specifies the length of the Hop-by-Hop Options
+ ///
+ UINT8 HdrExtLen;
+ ///
+ /// Header-Specific Data
+ ///
+} IP6_EXT_HDR;
+
+STATIC_ASSERT (
+ sizeof (IP6_EXT_HDR) == 2,
+ "The combined size of Next Header and Len is two 8 bit fields"
+ );
+
+//
+// IPv6 extension headers contain an 8-bit length field which describes the size of
+// the header. However, the length field only includes the size of the extension
+// header options, not the size of the first 8 bytes of the header. Therefore, in
+// order to calculate the full size of the extension header, we add 1 (to account
+// for the first 8 bytes omitted by the length field reporting) and then multiply
+// by 8 (since the size is represented in 8-byte units).
+//
+// a is the length field of the extension header (UINT8)
+// The result may be up to 2046 octets (UINT16)
+//
+#define IP6_HDR_EXT_LEN(a) (((UINT16)((UINT8)(a)) + 1) * 8)
+
+// This is the maxmimum length permissible by a extension header
+// Length is UINT8 of 8 octets not including the first 8 octets
+#define IP6_MAX_EXT_DATA_LENGTH (IP6_HDR_EXT_LEN (MAX_UINT8) - sizeof(IP6_EXT_HDR))
+STATIC_ASSERT (
+ IP6_MAX_EXT_DATA_LENGTH == 2046,
+ "Maximum data length is ((MAX_UINT8 + 1) * 8) - 2"
+ );
+
typedef struct _IP6_FRAGMENT_HEADER {
UINT8 NextHeader;
UINT8 Reserved;
--
2.40.0

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