1 files changed, 18 insertions, 16 deletions

diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index 6e4d5456a885..200eaf500696 100644
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c
@@ -24,8 +24,7 @@ static ssize_t max_phase_adjustment_show(struct device *dev,
 {
 	struct ptp_clock *ptp = dev_get_drvdata(dev);
 
-	return snprintf(page, PAGE_SIZE - 1, "%d\n",
-			ptp->info->getmaxphase(ptp->info));
+	return sysfs_emit(page, "%d\n", ptp->info->getmaxphase(ptp->info));
 }
 static DEVICE_ATTR_RO(max_phase_adjustment);
 
@@ -34,7 +33,7 @@ static ssize_t var##_show(struct device *dev,				\
 			   struct device_attribute *attr, char *page)	\
 {									\
 	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
-	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);	\
+	return sysfs_emit(page, "%d\n", ptp->info->var);	\
 }									\
 static DEVICE_ATTR(name, 0444, var##_show, NULL);
 
@@ -75,32 +74,36 @@ static ssize_t extts_fifo_show(struct device *dev,
 			       struct device_attribute *attr, char *page)
 {
 	struct ptp_clock *ptp = dev_get_drvdata(dev);
-	struct timestamp_event_queue *queue = &ptp->tsevq;
+	struct timestamp_event_queue *queue;
 	struct ptp_extts_event event;
 	unsigned long flags;
 	size_t qcnt;
 	int cnt = 0;
 
-	memset(&event, 0, sizeof(event));
+	cnt = list_count_nodes(&ptp->tsevqs);
+	if (cnt <= 0)
+		goto out;
 
-	if (mutex_lock_interruptible(&ptp->tsevq_mux))
-		return -ERESTARTSYS;
+	/* The sysfs fifo will always draw from the fist queue */
+	queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
+				 qlist);
 
+	memset(&event, 0, sizeof(event));
 	spin_lock_irqsave(&queue->lock, flags);
 	qcnt = queue_cnt(queue);
 	if (qcnt) {
 		event = queue->buf[queue->head];
-		queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
+		/* Paired with READ_ONCE() in queue_cnt() */
+		WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
 	}
 	spin_unlock_irqrestore(&queue->lock, flags);
 
 	if (!qcnt)
 		goto out;
 
-	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
-		       event.index, event.t.sec, event.t.nsec);
+	cnt = sysfs_emit(page, "%u %lld %u\n",
+			 event.index, event.t.sec, event.t.nsec);
 out:
-	mutex_unlock(&ptp->tsevq_mux);
 	return cnt;
 }
 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
@@ -190,7 +193,7 @@ static ssize_t n_vclocks_show(struct device *dev,
 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
 		return -ERESTARTSYS;
 
-	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
+	size = sysfs_emit(page, "%u\n", ptp->n_vclocks);
 
 	mutex_unlock(&ptp->n_vclocks_mux);
 
@@ -266,7 +269,7 @@ static ssize_t max_vclocks_show(struct device *dev,
 	struct ptp_clock *ptp = dev_get_drvdata(dev);
 	ssize_t size;
 
-	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
+	size = sysfs_emit(page, "%u\n", ptp->max_vclocks);
 
 	return size;
 }
@@ -281,7 +284,7 @@ static ssize_t max_vclocks_store(struct device *dev,
 	size_t size;
 	u32 max;
 
-	if (kstrtou32(buf, 0, &max) || max == 0)
+	if (kstrtou32(buf, 0, &max) || max == 0 || max > PTP_MAX_VCLOCKS_LIMIT)
 		return -EINVAL;
 
 	if (max == ptp->max_vclocks)
@@ -293,8 +296,7 @@ static ssize_t max_vclocks_store(struct device *dev,
 	if (max < ptp->n_vclocks)
 		goto out;
 
-	size = sizeof(int) * max;
-	vclock_index = kzalloc(size, GFP_KERNEL);
+	vclock_index = kcalloc(max, sizeof(int), GFP_KERNEL);
 	if (!vclock_index) {
 		err = -ENOMEM;
 		goto out;