[ 078/123] sparc64: Fix unrolled AES 256-bit key loops.

From: Greg Kroah-Hartman
Date: Wed Jan 09 2013 - 16:07:31 EST


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

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


From: "David S. Miller" <davem@xxxxxxxxxxxxx>

[ Upstream commit 9f28ffc03e93343ac04874fda9edb7affea45165 ]

The basic scheme of the block mode assembler is that we start by
enabling the FPU, loading the key into the floating point registers,
then iterate calling the encrypt/decrypt routine for each block.

For the 256-bit key cases, we run short on registers in the unrolled
loops.

So the {ENCRYPT,DECRYPT}_256_2() macros reload the key registers that
get clobbered.

The unrolled macros, {ENCRYPT,DECRYPT}_256(), are not mindful of this.

So if we have a mix of multi-block and single-block calls, the
single-block unrolled 256-bit encrypt/decrypt can run with some
of the key registers clobbered.

Handle this by always explicitly loading those registers before using
the non-unrolled 256-bit macro.

This was discovered thanks to all of the new test cases added by
Jussi Kivilinna.

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/sparc/crypto/aes_asm.S | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)

--- a/arch/sparc/crypto/aes_asm.S
+++ b/arch/sparc/crypto/aes_asm.S
@@ -1024,7 +1024,11 @@ ENTRY(aes_sparc64_ecb_encrypt_256)
add %o2, 0x20, %o2
brlz,pt %o3, 11f
nop
-10: ldx [%o1 + 0x00], %g3
+10: ldd [%o0 + 0xd0], %f56
+ ldd [%o0 + 0xd8], %f58
+ ldd [%o0 + 0xe0], %f60
+ ldd [%o0 + 0xe8], %f62
+ ldx [%o1 + 0x00], %g3
ldx [%o1 + 0x08], %g7
xor %g1, %g3, %g3
xor %g2, %g7, %g7
@@ -1128,9 +1132,9 @@ ENTRY(aes_sparc64_ecb_decrypt_256)
/* %o0=&key[key_len], %o1=input, %o2=output, %o3=len */
ldx [%o0 - 0x10], %g1
subcc %o3, 0x10, %o3
+ ldx [%o0 - 0x08], %g2
be 10f
- ldx [%o0 - 0x08], %g2
- sub %o0, 0xf0, %o0
+ sub %o0, 0xf0, %o0
1: ldx [%o1 + 0x00], %g3
ldx [%o1 + 0x08], %g7
ldx [%o1 + 0x10], %o4
@@ -1154,7 +1158,11 @@ ENTRY(aes_sparc64_ecb_decrypt_256)
add %o2, 0x20, %o2
brlz,pt %o3, 11f
nop
-10: ldx [%o1 + 0x00], %g3
+10: ldd [%o0 + 0x18], %f56
+ ldd [%o0 + 0x10], %f58
+ ldd [%o0 + 0x08], %f60
+ ldd [%o0 + 0x00], %f62
+ ldx [%o1 + 0x00], %g3
ldx [%o1 + 0x08], %g7
xor %g1, %g3, %g3
xor %g2, %g7, %g7
@@ -1511,11 +1519,11 @@ ENTRY(aes_sparc64_ctr_crypt_256)
add %o2, 0x20, %o2
brlz,pt %o3, 11f
nop
- ldd [%o0 + 0xd0], %f56
+10: ldd [%o0 + 0xd0], %f56
ldd [%o0 + 0xd8], %f58
ldd [%o0 + 0xe0], %f60
ldd [%o0 + 0xe8], %f62
-10: xor %g1, %g3, %o5
+ xor %g1, %g3, %o5
MOVXTOD_O5_F0
xor %g2, %g7, %o5
MOVXTOD_O5_F2


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