[PATCH 4.19 023/105] crypto: vmx - fix copy-paste error in CTR mode

From: Greg Kroah-Hartman
Date: Mon May 20 2019 - 08:24:20 EST


From: Daniel Axtens <dja@xxxxxxxxxx>

commit dcf7b48212c0fab7df69e84fab22d6cb7c8c0fb9 upstream.

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 MosnÃÄek <omosnacek@xxxxxxxxx>
Fixes: 5c380d623ed3 ("crypto: vmx - Add support for VMS instructions by ASM")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Daniel Axtens <dja@xxxxxxxxxx>
Tested-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Tested-by: Ondrej Mosnacek <omosnacek@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/crypto/vmx/aesp8-ppc.pl | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- 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: