[PATCH v3 2/8] drm/amdkfd: Correct SMI event read size

[Philip Yang <Philip.Yang@xxxxxxx>]

sizeof(buf) is 8 bytes because it is defined as unsigned char *buf,
each SMI event read only copy max 8 bytes to user buffer. Correct this
by using the buf allocate size.

Use KFD_SMI_EVENT_MSG_SIZE to define msg size, the same size will be
used in user space to alloc the msg receive buffer.

Signed-off-by: Philip Yang <Philip.Yang@xxxxxxx>
Reviewed-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
---
 drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
index f9eafc796e70..ce78bbd360da 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
@@ -82,7 +82,8 @@ static ssize_t kfd_smi_ev_read(struct file *filep, char __user *user,
 	struct kfd_smi_client *client = filep->private_data;
 	unsigned char *buf;
 
-	buf = kmalloc_array(MAX_KFIFO_SIZE, sizeof(*buf), GFP_KERNEL);
+	size = min_t(size_t, size, MAX_KFIFO_SIZE);
+	buf = kmalloc(size, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
@@ -96,7 +97,7 @@ static ssize_t kfd_smi_ev_read(struct file *filep, char __user *user,
 		ret = -EAGAIN;
 		goto ret_err;
 	}
-	to_copy = min3(size, sizeof(buf), to_copy);
+	to_copy = min(size, to_copy);
 	ret = kfifo_out(&client->fifo, buf, to_copy);
 	spin_unlock(&client->lock);
 	if (ret <= 0) {
@@ -183,7 +184,7 @@ void kfd_smi_event_update_gpu_reset(struct kfd_dev *dev, bool post_reset)
 	 * 1 byte event + 1 byte space + 8 bytes seq num +
 	 * 1 byte \n + 1 byte \0 = 12
 	 */
-	char fifo_in[12];
+	char fifo_in[KFD_SMI_EVENT_MSG_SIZE];
 	int len;
 	unsigned int event;
 
@@ -215,7 +216,7 @@ void kfd_smi_event_update_thermal_throttling(struct kfd_dev *dev,
 	 * 1 byte : + 16 byte thermal_interupt_counter + 1 byte \n +
 	 * 1 byte \0 = 37
 	 */
-	char fifo_in[37];
+	char fifo_in[KFD_SMI_EVENT_MSG_SIZE];
 	int len;
 
 	if (list_empty(&dev->smi_clients))
@@ -235,7 +236,7 @@ void kfd_smi_event_update_vmfault(struct kfd_dev *dev, uint16_t pasid)
 	/* 1 byte event + 1 byte space + 25 bytes msg + 1 byte \n +
 	 * 1 byte \0 = 29
 	 */
-	char fifo_in[29];
+	char fifo_in[KFD_SMI_EVENT_MSG_SIZE];
 	int len;
 
 	if (list_empty(&dev->smi_clients))
-- 
2.17.1