From: Dan Carpenter <redacted>

commit 19f1bc7edf0f97186810e13a88f5b62069d89097 upstream.

If copy_from_user() or kstrtoull() fail then the correct behavior is to
return a negative error code.

Link: https://lore.kernel.org/r/YEsbU/UxYypVrC7/@mwanda
Fixes: f9bb2da11db8 ("[SCSI] lpfc 8.3.27: T10 additions for SLI4")
Signed-off-by: Dan Carpenter <redacted>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/scsi/lpfc/lpfc_debugfs.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c

@@ -2423,7 +2423,7 @@ lpfc_debugfs_dif_err_write(struct file *
 	memset(dstbuf, 0, 33);
 	size = (nbytes < 32) ? nbytes : 32;
 	if (copy_from_user(dstbuf, buf, size))
-		return 0;
+		return -EFAULT;
 
 	if (dent == phba->debug_InjErrLBA) {
 		if ((dstbuf[0] == 'o') && (dstbuf[1] == 'f') &&

@@ -2432,7 +2432,7 @@ lpfc_debugfs_dif_err_write(struct file *
 	}
 
 	if ((tmp == 0) && (kstrtoull(dstbuf, 0, &tmp)))
-		return 0;
+		return -EINVAL;
 
 	if (dent == phba->debug_writeGuard)
 		phba->lpfc_injerr_wgrd_cnt = (uint32_t)tmp;