From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 23 Apr 2020 03:20:52 +0000 (-0400)
Subject: lpfc_debugfs: get rid of pointless access_ok()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e6c0433e270ae96fb62fd30cf7c2c7bf57d5391f;p=linux.git

lpfc_debugfs: get rid of pointless access_ok()

	No, you do NOT need to "protect copy from user" that way.
Incidentally, your userland ABI stinks.  I understand that you
wanted to accept "reset" and "reset\n" as equivalent, but I suspect
that accepting "reset this, you !@^!@!" had been an accident.
Nothing to do about that now - it is a userland ABI...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index 8a6e02aa553fc..5a754fb5f8546 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -2166,10 +2166,6 @@ lpfc_debugfs_lockstat_write(struct file *file, const char __user *buf,
 	char *pbuf;
 	int i;
 
-	/* Protect copy from user */
-	if (!access_ok(buf, nbytes))
-		return -EFAULT;
-
 	memset(mybuf, 0, sizeof(mybuf));
 
 	if (copy_from_user(mybuf, buf, nbytes))
@@ -2621,10 +2617,6 @@ lpfc_debugfs_multixripools_write(struct file *file, const char __user *buf,
 	if (nbytes > 64)
 		nbytes = 64;
 
-	/* Protect copy from user */
-	if (!access_ok(buf, nbytes))
-		return -EFAULT;
-
 	memset(mybuf, 0, sizeof(mybuf));
 
 	if (copy_from_user(mybuf, buf, nbytes))
@@ -2787,10 +2779,6 @@ lpfc_debugfs_scsistat_write(struct file *file, const char __user *buf,
 	char mybuf[6] = {0};
 	int i;
 
-	/* Protect copy from user */
-	if (!access_ok(buf, nbytes))
-		return -EFAULT;
-
 	if (copy_from_user(mybuf, buf, (nbytes >= sizeof(mybuf)) ?
 				       (sizeof(mybuf) - 1) : nbytes))
 		return -EFAULT;