[PATCH 4.14 079/173] s390/crypto: Fix return code checking in cbc_paes_crypt()

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ingo Franzki <ifranzki@xxxxxxxxxxxxx>

commit b81126e01a8c6048249955feea46c8217ebefa91 upstream.

The return code of cpacf_kmc() is less than the number of
bytes to process in case of an error, not greater.
The crypt routines for the other cipher modes already have
this correctly.

Cc: stable@xxxxxxxxxxxxxxx # v4.11+
Fixes: 279378430768 ("s390/crypt: Add protected key AES module")
Signed-off-by: Ingo Franzki <ifranzki@xxxxxxxxxxxxx>
Acked-by: Harald Freudenberger <freude@xxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/s390/crypto/paes_s390.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/s390/crypto/paes_s390.c
+++ b/arch/s390/crypto/paes_s390.c
@@ -212,7 +212,7 @@ static int cbc_paes_crypt(struct blkciph
 			      walk->dst.virt.addr, walk->src.virt.addr, n);
 		if (k)
 			ret = blkcipher_walk_done(desc, walk, nbytes - k);
-		if (n < k) {
+		if (k < n) {
 			if (__cbc_paes_set_key(ctx) != 0)
 				return blkcipher_walk_done(desc, walk, -EIO);
 			memcpy(param.key, ctx->pk.protkey, MAXPROTKEYSIZE);