File mempcpy-avx512.patch of Package glibc

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File mempcpy-avx512.patch of Package glibc

[BZ #23196]
	CVE-2018-11237
	* sysdeps/x86_64/multiarch/memcpy-avx512-no-vzeroupper.S
	(L(preloop_large)): Save initial destination pointer in %r11 and
	use it instead of %rax after the loop.
	* string/test-mempcpy.c (MIN_PAGE_SIZE): Define.

Index: glibc-2.22/string/test-mempcpy.c
===================================================================
--- glibc-2.22.orig/string/test-mempcpy.c
+++ glibc-2.22/string/test-mempcpy.c
@@ -18,6 +18,7 @@
    <http://www.gnu.org/licenses/>.  */
 
 #define MEMCPY_RESULT(dst, len) (dst) + (len)
+#define MIN_PAGE_SIZE 131072
 #define TEST_MAIN
 #define TEST_NAME "mempcpy"
 #include "test-string.h"
Index: glibc-2.22/sysdeps/x86_64/multiarch/memcpy-avx512-no-vzeroupper.S
===================================================================
--- glibc-2.22.orig/sysdeps/x86_64/multiarch/memcpy-avx512-no-vzeroupper.S
+++ glibc-2.22/sysdeps/x86_64/multiarch/memcpy-avx512-no-vzeroupper.S
@@ -333,6 +333,7 @@ L(preloop_large):
 	vmovups	(%rsi), %zmm4
 	vmovups	0x40(%rsi), %zmm5
 
+	mov	%rdi, %r11
 /* Align destination for access with non-temporal stores in the loop.  */
 	mov	%rdi, %r8
 	and	$-0x80, %rdi
@@ -363,8 +364,8 @@ L(gobble_256bytes_nt_loop):
 	cmp	$256, %rdx
 	ja	L(gobble_256bytes_nt_loop)
 	sfence
-	vmovups	%zmm4, (%rax)
-	vmovups	%zmm5, 0x40(%rax)
+	vmovups	%zmm4, (%r11)
+	vmovups	%zmm5, 0x40(%r11)
 	jmp	L(check)
 
 L(preloop_large_bkw):

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File mempcpy-avx512.patch of Package glibc

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