cryptd_queue_worker attempts to prevent simultaneous accesses to crypto
workqueue by cryptd_enqueue_request using preempt_disable/preempt_enable.
However cryptd_enqueue_request might be called from interrupt context,
so add local_irq_save/local_irq_restore to prevent data corruption and
panics.
Bug report at http://marc.info/?l=linux-crypto-vger&m=134858649616319&w=2
Cc: [email protected]
Reported-by: Gurucharan Shetty <[email protected]>
Tested-by: Gurucharan Shetty <[email protected]>
Signed-off-by: Jussi Kivilinna <[email protected]>
---
crypto/cryptd.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/crypto/cryptd.c b/crypto/cryptd.c
index 671d4d6..8f62d06 100644
--- a/crypto/cryptd.c
+++ b/crypto/cryptd.c
@@ -133,16 +133,23 @@ static int cryptd_enqueue_request(struct cryptd_queue *queue,
* do. */
static void cryptd_queue_worker(struct work_struct *work)
{
+ unsigned long flags;
struct cryptd_cpu_queue *cpu_queue;
struct crypto_async_request *req, *backlog;
cpu_queue = container_of(work, struct cryptd_cpu_queue, work);
- /* Only handle one request at a time to avoid hogging crypto
+ /*
+ * Only handle one request at a time to avoid hogging crypto
* workqueue. preempt_disable/enable is used to prevent
- * being preempted by cryptd_enqueue_request() */
+ * being preempted by cryptd_enqueue_request(). local_irq_save/restore
+ * is used to prevent cryptd_enqueue_request() being accessed from
+ * interrupts.
+ */
+ local_irq_save(flags);
preempt_disable();
backlog = crypto_get_backlog(&cpu_queue->queue);
req = crypto_dequeue_request(&cpu_queue->queue);
+ local_irq_restore(flags);
preempt_enable();
if (!req)
You should be disabling software interrupts, not hardware ones.
Quoting David Miller <[email protected]>:
>
> You should be disabling software interrupts, not hardware ones.
>
Ok, I'll roll out v2.
-Jussi