From: Ingo Franzki <ifranzki@linux.ibm.com>
Date: Mon, 27 Aug 2018 14:28:47 +0200
Subject: s390/crypto: Fix return code checking in cbc_paes_crypt()
Patch-mainline: v4.19-rc4
Git-commit: b81126e01a8c6048249955feea46c8217ebefa91
References: bnc#1108323, LTC#171709
Description: s390/crypto: Fix return code checking in cbc_paes_crypt.
Symptom: A protected key is not re-transformed when it became invalid
Problem: The return code of cpacf_kmc() is less than the number of
bytes to process in case of an error, not greater.
Solution: Correct return code checking.
Reproduction: -
Upstream-Description:
s390/crypto: Fix return code checking in cbc_paes_crypt()
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@vger.kernel.org # v4.11+
Fixes: 279378430768 ("s390/crypt: Add protected key AES module")
Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
Acked-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
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 blkcipher_desc *desc, unsigned long modifier,
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);