s390/crypto: Fix return code handling at skcipher_walk_done in PAES algorithms

All the 4 PAES cipher processing loops were not checking the return
value of skcipher_walk_done() immediately after calling it. This could
lead to error masking when both the walk operation failed and a
subsequent key conversion was needed (k < n condition).

Add immediate error checks after skcipher_walk_done() in all main
processing loops (ECB, CBC, CTR, XTS modes) to ensure walk errors are
properly propagated and not masked by subsequent operations.

With that comes a slight rework around the skcipher_walk_done()
invocation. It is now necessary to check if the walk has already been
finalized (walk->nbytes is then 0) or not to avoid double
de-allocation of resources held by the walk.

Fixes: 6cd87cb5ef6c ("s390/crypto: Rework protected key AES for true asynch support")
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Cc: stable@vger.kernel.org # 6.16+
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

0 files changed, 0 insertions, 0 deletions