crypto: aesni-intel - fix unaligned cbc decrypt for x86-32

commit 7c8d51848a88aafdb68f42b6b650c83485ea2f84 upstream.

The 32 bit variant of cbc(aes) decrypt is using instructions requiring
128 bit aligned memory locations but fails to ensure this constraint in
the code. Fix this by loading the data into intermediate registers with
load unaligned instructions.

This fixes reported general protection faults related to aesni.

References: https://bugzilla.kernel.org/show_bug.cgi?id=43223
Reported-by: Daniel <garkein@mailueberfall.de>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S
index be6d9e3..3470624 100644 (file)
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -2460,10 +2460,12 @@ ENTRY(aesni_cbc_dec)
        pxor IN3, STATE4
        movaps IN4, IV
 #else
-       pxor (INP), STATE2
-       pxor 0x10(INP), STATE3
        pxor IN1, STATE4
        movaps IN2, IV
+       movups (INP), IN1
+       pxor IN1, STATE2
+       movups 0x10(INP), IN2
+       pxor IN2, STATE3
 #endif
        movups STATE1, (OUTP)
        movups STATE2, 0x10(OUTP)