summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorMiaoqing Pan <miaoqing@codeaurora.org>2017-06-27 16:31:54 +0200
committerKalle Valo <kvalo@qca.qualcomm.com>2017-06-28 18:54:38 +0200
commit473becac4b310dd720a0f5e07ce149a09467f1a4 (patch)
tree3d4053e20aac695dfd62df4406f4e38abbe4575a
parentath9k: fix an invalid pointer dereference in ath9k_rng_stop() (diff)
downloadlinux-473becac4b310dd720a0f5e07ce149a09467f1a4.tar.xz
linux-473becac4b310dd720a0f5e07ce149a09467f1a4.zip
ath9k: avoid potential freezing during random generator read
In the worst case, ath9k_rng_stop() may take 10s to stop rng kthread. The time is too long for users, use wait_event_interruptible_timeout() instead of msleep_interruptible(), wakup immediately once kthread_should_stop() is true. Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org> Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
-rw-r--r--drivers/net/wireless/ath/ath9k/rng.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/net/wireless/ath/ath9k/rng.c b/drivers/net/wireless/ath/ath9k/rng.c
index 73f46fb3e83a..f9d3d6eedd3c 100644
--- a/drivers/net/wireless/ath/ath9k/rng.c
+++ b/drivers/net/wireless/ath/ath9k/rng.c
@@ -24,6 +24,8 @@
#define ATH9K_RNG_BUF_SIZE 320
#define ATH9K_RNG_ENTROPY(x) (((x) * 8 * 10) >> 5) /* quality: 10/32 */
+static DECLARE_WAIT_QUEUE_HEAD(rng_queue);
+
static int ath9k_rng_data_read(struct ath_softc *sc, u32 *buf, u32 buf_size)
{
int i, j;
@@ -85,7 +87,9 @@ static int ath9k_rng_kthread(void *data)
ATH9K_RNG_BUF_SIZE);
if (unlikely(!bytes_read)) {
delay = ath9k_rng_delay_get(++fail_stats);
- msleep_interruptible(delay);
+ wait_event_interruptible_timeout(rng_queue,
+ kthread_should_stop(),
+ msecs_to_jiffies(delay));
continue;
}