[PATCH 4.12 68/84] crypto: sha1-ssse3 - Disable avx2

[Greg Kroah-Hartman]

4.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

commit b82ce24426a4071da9529d726057e4e642948667 upstream.

It has been reported that sha1-avx2 can cause page faults by reading
beyond the end of the input.  This patch disables it until it can be
fixed.

Fixes: 7c1da8d0d046 ("crypto: sha - SHA1 transform x86_64 AVX2")
Reported-by: Jan Stancek <jstancek@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/crypto/sha1_ssse3_glue.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/crypto/sha1_ssse3_glue.c
+++ b/arch/x86/crypto/sha1_ssse3_glue.c
@@ -201,7 +201,7 @@ asmlinkage void sha1_transform_avx2(u32
 
 static bool avx2_usable(void)
 {
-	if (avx_usable() && boot_cpu_has(X86_FEATURE_AVX2)
+	if (false && avx_usable() && boot_cpu_has(X86_FEATURE_AVX2)
 		&& boot_cpu_has(X86_FEATURE_BMI1)
 		&& boot_cpu_has(X86_FEATURE_BMI2))
 		return true;