[PATCH 3.18 23/28] crypto: sha1-ssse3 - Disable avx2

From: Greg Kroah-Hartman
Date: Wed Jul 19 2017 - 07:20:33 EST


3.18-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
@@ -224,7 +224,7 @@ static bool __init avx_usable(void)
#ifdef CONFIG_AS_AVX2
static bool __init avx2_usable(void)
{
- if (avx_usable() && cpu_has_avx2 && boot_cpu_has(X86_FEATURE_BMI1) &&
+ if (false && avx_usable() && cpu_has_avx2 && boot_cpu_has(X86_FEATURE_BMI1) &&
boot_cpu_has(X86_FEATURE_BMI2))
return true;