crypto: vmx - fix copy-paste error in CTR mode

The original assembly imported from OpenSSL has two copy-paste
errors in handling CTR mode. When dealing with a 2 or 3 block tail,
the code branches to the CBC decryption exit path, rather than to
the CTR exit path.

This leads to corruption of the IV, which leads to subsequent blocks
being corrupted.

This can be detected with libkcapi test suite, which is available at
https://github.com/smuellerDD/libkcapi

Reported-by: Ondrej Mosnáček <omosnacek@gmail.com>
Fixes: 5c380d623ed3 ("crypto: vmx - Add support for VMS instructions by ASM")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Axtens <dja@axtens.net>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/vmx/aesp8-ppc.pl b/drivers/crypto/vmx/aesp8-ppc.pl
index d6a9f63d65ba2d6d3a0d903d5167808351cd603c..de78282b8f4473d6884d66240c1fc31284599803 100644 (file)
--- a/drivers/crypto/vmx/aesp8-ppc.pl
+++ b/drivers/crypto/vmx/aesp8-ppc.pl
@@ -1854,7 +1854,7 @@ Lctr32_enc8x_three:
        stvx_u          $out1,$x10,$out
        stvx_u          $out2,$x20,$out
        addi            $out,$out,0x30
-       b               Lcbc_dec8x_done
+       b               Lctr32_enc8x_done
 
 .align 5
 Lctr32_enc8x_two:
@@ -1866,7 +1866,7 @@ Lctr32_enc8x_two:
        stvx_u          $out0,$x00,$out
        stvx_u          $out1,$x10,$out
        addi            $out,$out,0x20
-       b               Lcbc_dec8x_done
+       b               Lctr32_enc8x_done
 
 .align 5
 Lctr32_enc8x_one: