[PATCH] crypto: vmx - fix copy-paste error in CTR mode

[Daniel Axtens]

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 at gmail.com>
Fixes: 5c380d623ed3 ("crypto: vmx - Add support for VMS instructions by ASM")
Cc: stable at vger.kernel.org
Signed-off-by: Daniel Axtens <dja at axtens.net>
---
 drivers/crypto/vmx/aesp8-ppc.pl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/vmx/aesp8-ppc.pl b/drivers/crypto/vmx/aesp8-ppc.pl
index d6a9f63d65ba..de78282b8f44 100644
--- 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:
-- 
2.19.1