From 0e0836625b0a5efb1b86b2836b0d2349c66753de Mon Sep 17 00:00:00 2001 From: =?utf8?q?Christian=20L=C3=BCtke-Stetzkamp?= Date: Sat, 7 Apr 2018 10:16:24 +0200 Subject: [PATCH] staging: mt7621-mmc: Fix: copy_from_user() returns a positive value MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit copy_from_user() returns a positive value in case of an error, to fix this the check is turned around, also a better return value is chosen. Reported-by: Dan Carpenter Suggested-by: Dan Carpenter Signed-off-by: Christian Lütke-Stetzkamp Reviewed-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- drivers/staging/mt7621-mmc/dbg.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/staging/mt7621-mmc/dbg.c b/drivers/staging/mt7621-mmc/dbg.c index ec95f6d..9a1809d 100644 --- a/drivers/staging/mt7621-mmc/dbg.c +++ b/drivers/staging/mt7621-mmc/dbg.c @@ -265,9 +265,8 @@ static ssize_t msdc_debug_proc_write(struct file *file, if (count > 255) count = 255; - ret = copy_from_user(cmd_buf, buf, count); - if (ret < 0) - return -1; + if (copy_from_user(cmd_buf, buf, count)) + return -EFAULT; cmd_buf[count] = '\0'; printk("msdc Write %s\n", cmd_buf); -- 2.7.4