From e1e1125b5ce110ef53770b4e6e18a34f772ab6eb Mon Sep 17 00:00:00 2001
From: wzc <u201911736@hust.edu.cn>
Date: Wed, 26 Apr 2023 17:08:15 +0800
Subject: [PATCH 60/60] backport-CVE-2023-1255,The buffer overread happens on decrypts of 4 mod 5 sizes.Unless the memory just after the buffer is unmapped this is harmless.

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Tom Cosgrove <tom.cosgrove@arm.com>
(Merged from https://github.com/openssl/openssl/pull/20759)

(cherry picked from commit 72dfe46550ee1f1bbfacd49f071419365bc23304)
---
 CHANGES.md                 | 10 ++++++++++
 NEWS.md                    |  2 ++
 ...//crypto/aes/asm/aesv8-armx.pl         |  4 +++-
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/CHANGES.md b/CHANGES.md
index 7cdd9d9..6c33bf9 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -30,6 +30,15 @@ breaking changes, and mappings for the large list of deprecated functions.
 
 ### Changes between 3.0.7 and 3.0.8 [7 Feb 2023]
 
+ * Fixed buffer overread in AES-XTS decryption on ARM 64 bit platforms which
+   happens if the buffer size is 4 mod 5. This can trigger a crash of an
+   application using AES-XTS decryption if the memory just after the buffer
+   being decrypted is not mapped.
+   Thanks to Anton Romanov (Amazon) for discovering the issue.
+   ([CVE-2023-1255])
+
+   *Nevine Ebeid*
+
  * Fixed NULL dereference during PKCS7 data verification.
 
    A NULL pointer can be dereferenced when signatures are being
@@ -19578,6 +19587,7 @@ ndif
 
 <!-- Links -->
 
+[CVE-2023-1255]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-1255
 [CVE-2023-0401]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0401
 [CVE-2023-0286]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0286
 [CVE-2023-0217]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0217
diff --git a/NEWS.md b/NEWS.md
index 36dbfa7..86b1410 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -20,6 +20,7 @@ OpenSSL 3.0
 
 ### Major changes between OpenSSL 3.0.7 and OpenSSL 3.0.8 [7 Feb 2023]
 
+  * Fixed buffer overread in AES-XTS decryption on ARM 64 bit platforms ([CVE-2023-1255])
   * Fixed NULL dereference during PKCS7 data verification ([CVE-2023-0401])
   * Fixed X.400 address type confusion in X.509 GeneralName ([CVE-2023-0286])
   * Fixed NULL dereference validating DSA public key ([CVE-2023-0217])
@@ -1430,6 +1431,7 @@ OpenSSL 0.9.x
   * Support for various new platforms
 
 <!-- Links -->
+[CVE-2023-1255]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-1255
 [CVE-2023-0401]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0401
 [CVE-2023-0286]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0286
 [CVE-2023-0217]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0217
diff --git a/crypto/aes/asm/aesv8-armx.pl b/crypto/aes/asm/aesv8-armx.pl
index 6a7bf05..5701373 100644
--- a/crypto/aes/asm/aesv8-armx.pl
+++ b/crypto/aes/asm/aesv8-armx.pl
@@ -3353,7 +3353,7 @@ $code.=<<___	if ($flavour =~ /64/);
 .align	4
 .Lxts_dec_tail4x:
 	add	$inp,$inp,#16
-	vld1.32	{$dat0},[$inp],#16
+	tst     $tailcnt,#0xf
 	veor	$tmp1,$dat1,$tmp0
 	vst1.8	{$tmp1},[$out],#16
 	veor	$tmp2,$dat2,$tmp2
@@ -3362,6 +3362,8 @@ $code.=<<___	if ($flavour =~ /64/);
 	veor	$tmp4,$dat4,$tmp4
 	vst1.8	{$tmp3-$tmp4},[$out],#32
 
+    b.eq    .Lxts_dec_abort
+    vld1.32 {$dat0},[$inp],#16
 	b	.Lxts_done
 .align	4
 .Lxts_outer_dec_tail:
-- 
2.37.0.windows.1