[PATCH 3.10 113/139] crypto: caam - fix signals handling

From: Willy Tarreau
Date: Wed Nov 01 2017 - 17:39:12 EST


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).

Cc: <stable@xxxxxxxxxxxxxxx>
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: Willy Tarreau <w@xxxxxx>
---
drivers/crypto/caam/caamhash.c | 2 +-
drivers/crypto/caam/key_gen.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/caam/caamhash.c b/drivers/crypto/caam/caamhash.c
index e9d8b23..34815a7 100644
--- a/drivers/crypto/caam/caamhash.c
+++ b/drivers/crypto/caam/caamhash.c
@@ -476,7 +476,7 @@ static int hash_digest_key(struct caam_hash_ctx *ctx, const u8 *key_in,
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, "digested key@"xstr(__LINE__)": ",
diff --git a/drivers/crypto/caam/key_gen.c b/drivers/crypto/caam/key_gen.c
index 87138d2..fd6bc0b 100644
--- a/drivers/crypto/caam/key_gen.c
+++ b/drivers/crypto/caam/key_gen.c
@@ -107,7 +107,7 @@ int gen_split_key(struct device *jrdev, u8 *key_out, int split_key_len,
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@"xstr(__LINE__)": ",
--
2.8.0.rc2.1.gbe9624a