[34-longterm 119/209] crypto: padlock - Fix AES-CBC handling on odd-block-sized input

From: Paul Gortmaker
Date: Thu Apr 14 2011 - 13:57:46 EST

From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

| This is a commit scheduled for the next v2.6.34 longterm release. |
| If you see a problem with using this for longterm, please comment.|

commit c054a076a1bd4731820a9c4d638b13d5c9bf5935 upstream.

On certain VIA chipsets AES-CBC requires the input/output to be
a multiple of 64 bytes. We had a workaround for this but it was
buggy as it sent the whole input for processing when it is meant
to only send the initial number of blocks which makes the rest
a multiple of 64 bytes.

As expected this causes memory corruption whenever the workaround
kicks in.

Reported-by: Phil Sutter <phil@xxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
drivers/crypto/padlock-aes.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c
index 2e992bc..8a515ba 100644
--- a/drivers/crypto/padlock-aes.c
+++ b/drivers/crypto/padlock-aes.c
@@ -286,7 +286,7 @@ static inline u8 *padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key,
if (initial)
asm volatile (".byte 0xf3,0x0f,0xa7,0xd0" /* rep xcryptcbc */
: "+S" (input), "+D" (output), "+a" (iv)
- : "d" (control_word), "b" (key), "c" (count));
+ : "d" (control_word), "b" (key), "c" (initial));

asm volatile (".byte 0xf3,0x0f,0xa7,0xd0" /* rep xcryptcbc */
: "+S" (input), "+D" (output), "+a" (iv)

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