[PATCH] firmware: tegra: switch over to memdup_user()

[Qing Wang]

This patch fixes the following Coccinelle warning:

drivers/firmware/tegra/bpmp-debugfs.c:379: WARNING opportunity for memdup_user

Use memdup_user rather than duplicating its implementation
This is a little bit restricted to reduce false positives

Signed-off-by: Qing Wang <wangqing@xxxxxxxx>
---
 drivers/firmware/tegra/bpmp-debugfs.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/drivers/firmware/tegra/bpmp-debugfs.c b/drivers/firmware/tegra/bpmp-debugfs.c
index 6d66fe0..0435709
--- a/drivers/firmware/tegra/bpmp-debugfs.c
+++ b/drivers/firmware/tegra/bpmp-debugfs.c
@@ -376,18 +376,11 @@ static ssize_t bpmp_debug_store(struct file *file, const char __user *buf,
 	if (!filename)
 		return -ENOENT;
 
-	databuf = kmalloc(count, GFP_KERNEL);
-	if (!databuf)
-		return -ENOMEM;
-
-	if (copy_from_user(databuf, buf, count)) {
-		err = -EFAULT;
-		goto free_ret;
-	}
+	databuf = memdup_user(buf, count);
+	if (IS_ERR(databuf))
+		return ERR_PTR(PTR_ERR(databuf));
 
 	err = mrq_debug_write(bpmp, filename, databuf, count);
-
-free_ret:
 	kfree(databuf);
 
 	return err ?: count;
-- 
2.7.4