4.16-stable review patch. If anyone has any objections, please let me know.
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From: Antoine Tenart antoine.tenart@bootlin.com
[ Upstream commit b7007dbccd92f7b8c00e590020bee542a48c6a2c ]
When exiting a transformation, the cra_exit() helper is called in each driver providing one. The Inside Secure SafeXcel driver has one, which is responsible of freeing some areas and of sending one invalidation request to the crypto engine, to invalidate the context that was used during the transformation.
We could see in some setups (when lots of transformations were being used with a short lifetime, and hence lots of cra_exit() calls) NULL pointer dereferences and other weird issues. All these issues were coming from accessing the tfm context.
The issue is the invalidation request completion is checked using a wait_for_completion_interruptible() call in both the cipher and hash cra_exit() helpers. In some cases this was interrupted while the invalidation request wasn't processed yet. And then cra_exit() returned, and its caller was freeing the tfm instance. Only then the request was being handled by the SafeXcel driver, which lead to the said issues.
This patch fixes this by using wait_for_completion() calls in these specific cases.
Fixes: 1b44c5a60c13 ("crypto: inside-secure - add SafeXcel EIP197 crypto engine driver") Signed-off-by: Antoine Tenart antoine.tenart@bootlin.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/crypto/inside-secure/safexcel_cipher.c | 2 +- drivers/crypto/inside-secure/safexcel_hash.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/crypto/inside-secure/safexcel_cipher.c +++ b/drivers/crypto/inside-secure/safexcel_cipher.c @@ -456,7 +456,7 @@ static int safexcel_cipher_exit_inv(stru queue_work(priv->ring[ring].workqueue, &priv->ring[ring].work_data.work);
- wait_for_completion_interruptible(&result.completion); + wait_for_completion(&result.completion);
if (result.error) { dev_warn(priv->dev, --- a/drivers/crypto/inside-secure/safexcel_hash.c +++ b/drivers/crypto/inside-secure/safexcel_hash.c @@ -496,7 +496,7 @@ static int safexcel_ahash_exit_inv(struc queue_work(priv->ring[ring].workqueue, &priv->ring[ring].work_data.work);
- wait_for_completion_interruptible(&result.completion); + wait_for_completion(&result.completion);
if (result.error) { dev_warn(priv->dev, "hash: completion error (%d)\n",