[PATCH 06/20] n_hdlc_tty_read(): remove pointless access_ok()

From: Al Viro
Date: Sat May 09 2020 - 19:47:18 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

only copy_to_user() is done to the address in question

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/n_hdlc.c | 7 -------
1 file changed, 7 deletions(-)

diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 991f49ee4026..b09eac4b6d64 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -423,13 +423,6 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
struct n_hdlc_buf *rbuf;
DECLARE_WAITQUEUE(wait, current);

- /* verify user access to buffer */
- if (!access_ok(buf, nr)) {
- pr_warn("%s(%d) %s() can't verify user buffer\n",
- __FILE__, __LINE__, __func__);
- return -EFAULT;
- }
-
add_wait_queue(&tty->read_wait, &wait);

for (;;) {
--
2.11.0