[PATCH 3.16 107/192] crypto: caam - fix signals handling

[Ben Hutchings]

3.16.49-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Horia GeantÄ <horia.geanta@xxxxxxx>

commit 7459e1d25ffefa2b1be799477fcc1f6c62f6cec7 upstream.

Driver does not properly handle the case when signals interrupt
wait_for_completion_interruptible():
-it does not check for return value
-completion structure is allocated on stack; in case a signal interrupts
the sleep, it will go out of scope, causing the worker thread
(caam_jr_dequeue) to fail when it accesses it

wait_for_completion_interruptible() is replaced with uninterruptable
wait_for_completion().
We choose to block all signals while waiting for I/O (device executing
the split key generation job descriptor) since the alternative - in
order to have a deterministic device state - would be to flush the job
ring (aborting *all* in-progress jobs).

Fixes: 045e36780f115 ("crypto: caam - ahash hmac support")
Fixes: 4c1ec1f930154 ("crypto: caam - refactor key_gen, sg")
Signed-off-by: Horia GeantÄ <horia.geanta@xxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/crypto/caam/caamhash.c | 2 +-
 drivers/crypto/caam/key_gen.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/crypto/caam/caamhash.c
+++ b/drivers/crypto/caam/caamhash.c
@@ -478,7 +478,7 @@ static int hash_digest_key(struct caam_h
 	ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
 	if (!ret) {
 		/* in progress */
-		wait_for_completion_interruptible(&result.completion);
+		wait_for_completion(&result.completion);
 		ret = result.err;
 #ifdef DEBUG
 		print_hex_dump(KERN_ERR,
--- a/drivers/crypto/caam/key_gen.c
+++ b/drivers/crypto/caam/key_gen.c
@@ -103,7 +103,7 @@ int gen_split_key(struct device *jrdev,
 	ret = caam_jr_enqueue(jrdev, desc, split_key_done, &result);
 	if (!ret) {
 		/* in progress */
-		wait_for_completion_interruptible(&result.completion);
+		wait_for_completion(&result.completion);
 		ret = result.err;
 #ifdef DEBUG
 		print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",