This is a note to let you know that I've just added the patch titled

    crypto: aesni - fix "by8" variant for 128 bit keys

to the 3.18-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     crypto-aesni-fix-by8-variant-for-128-bit-keys.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 0b1e95b2fa0934c3a08db483979c70d3b287f50e Mon Sep 17 00:00:00 2001
From: Mathias Krause <[email protected]>
Date: Tue, 30 Dec 2014 22:50:54 +0100
Subject: crypto: aesni - fix "by8" variant for 128 bit keys

From: Mathias Krause <[email protected]>

commit 0b1e95b2fa0934c3a08db483979c70d3b287f50e upstream.

The "by8" counter mode optimization is broken for 128 bit keys with
input data longer than 128 bytes. It uses the wrong key material for
en- and decryption.

The key registers xkey0, xkey4, xkey8 and xkey12 need to be preserved
in case we're handling more than 128 bytes of input data -- they won't
get reloaded after the initial load. They must therefore be (a) loaded
on the first iteration and (b) be preserved for the latter ones. The
implementation for 128 bit keys does not comply with (a) nor (b).

Fix this by bringing the implementation back to its original source
and correctly load the key registers and preserve their values by
*not* re-using the registers for other purposes.

Kudos to James for reporting the issue and providing a test case
showing the discrepancies.

Reported-by: James Yonan <[email protected]>
Cc: Chandramouli Narayanan <[email protected]>
Signed-off-by: Mathias Krause <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/x86/crypto/aes_ctrby8_avx-x86_64.S |   46 ++++++++++++++++++++++++--------
 1 file changed, 35 insertions(+), 11 deletions(-)

--- a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
+++ b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
@@ -208,7 +208,7 @@ ddq_add_8:
 
        .if (klen == KEY_128)
                .if (load_keys)
-                       vmovdqa 3*16(p_keys), xkeyA
+                       vmovdqa 3*16(p_keys), xkey4
                .endif
        .else
                vmovdqa 3*16(p_keys), xkeyA
@@ -224,7 +224,7 @@ ddq_add_8:
        add     $(16*by), p_in
 
        .if (klen == KEY_128)
-               vmovdqa 4*16(p_keys), xkey4
+               vmovdqa 4*16(p_keys), xkeyB
        .else
                .if (load_keys)
                        vmovdqa 4*16(p_keys), xkey4
@@ -234,7 +234,12 @@ ddq_add_8:
        .set i, 0
        .rept by
                club XDATA, i
-               vaesenc xkeyA, var_xdata, var_xdata             /* key 3 */
+               /* key 3 */
+               .if (klen == KEY_128)
+                       vaesenc xkey4, var_xdata, var_xdata
+               .else
+                       vaesenc xkeyA, var_xdata, var_xdata
+               .endif
                .set i, (i +1)
        .endr
 
@@ -243,13 +248,18 @@ ddq_add_8:
        .set i, 0
        .rept by
                club XDATA, i
-               vaesenc xkey4, var_xdata, var_xdata             /* key 4 */
+               /* key 4 */
+               .if (klen == KEY_128)
+                       vaesenc xkeyB, var_xdata, var_xdata
+               .else
+                       vaesenc xkey4, var_xdata, var_xdata
+               .endif
                .set i, (i +1)
        .endr
 
        .if (klen == KEY_128)
                .if (load_keys)
-                       vmovdqa 6*16(p_keys), xkeyB
+                       vmovdqa 6*16(p_keys), xkey8
                .endif
        .else
                vmovdqa 6*16(p_keys), xkeyB
@@ -267,12 +277,17 @@ ddq_add_8:
        .set i, 0
        .rept by
                club XDATA, i
-               vaesenc xkeyB, var_xdata, var_xdata             /* key 6 */
+               /* key 6 */
+               .if (klen == KEY_128)
+                       vaesenc xkey8, var_xdata, var_xdata
+               .else
+                       vaesenc xkeyB, var_xdata, var_xdata
+               .endif
                .set i, (i +1)
        .endr
 
        .if (klen == KEY_128)
-               vmovdqa 8*16(p_keys), xkey8
+               vmovdqa 8*16(p_keys), xkeyB
        .else
                .if (load_keys)
                        vmovdqa 8*16(p_keys), xkey8
@@ -288,7 +303,7 @@ ddq_add_8:
 
        .if (klen == KEY_128)
                .if (load_keys)
-                       vmovdqa 9*16(p_keys), xkeyA
+                       vmovdqa 9*16(p_keys), xkey12
                .endif
        .else
                vmovdqa 9*16(p_keys), xkeyA
@@ -297,7 +312,12 @@ ddq_add_8:
        .set i, 0
        .rept by
                club XDATA, i
-               vaesenc xkey8, var_xdata, var_xdata             /* key 8 */
+               /* key 8 */
+               .if (klen == KEY_128)
+                       vaesenc xkeyB, var_xdata, var_xdata
+               .else
+                       vaesenc xkey8, var_xdata, var_xdata
+               .endif
                .set i, (i +1)
        .endr
 
@@ -306,7 +326,12 @@ ddq_add_8:
        .set i, 0
        .rept by
                club XDATA, i
-               vaesenc xkeyA, var_xdata, var_xdata             /* key 9 */
+               /* key 9 */
+               .if (klen == KEY_128)
+                       vaesenc xkey12, var_xdata, var_xdata
+               .else
+                       vaesenc xkeyA, var_xdata, var_xdata
+               .endif
                .set i, (i +1)
        .endr
 
@@ -412,7 +437,6 @@ ddq_add_8:
 /* main body of aes ctr load */
 
 .macro do_aes_ctrmain key_len
-
        cmp     $16, num_bytes
        jb      .Ldo_return2\key_len
 


Patches currently in stable-queue which might be from [email protected] are

queue-3.18/crypto-aesni-fix-by8-variant-for-128-bit-keys.patch
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