From: Dan Carpenter Date: Wed, 21 Aug 2019 07:16:11 +0000 Subject: [PATCH] bcache: Fix an error code in bch_dump_read() Message-Id: <20190821071611.GH26957@mwanda> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kernel-janitors@vger.kernel.org The copy_to_user() function returns the number of bytes remaining to be copied, but the intention here was to return -EFAULT if the copy fails. Fixes: cafe56359144 ("bcache: A block layer cache") Signed-off-by: Dan Carpenter --- Another option to fix this bug would be to return the number of bytes which were successfully copied. But probably -EFAULT is the right fix. drivers/md/bcache/debug.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c index 8b123be05254..336f43910383 100644 --- a/drivers/md/bcache/debug.c +++ b/drivers/md/bcache/debug.c @@ -178,10 +178,9 @@ static ssize_t bch_dump_read(struct file *file, char __user *buf, while (size) { struct keybuf_key *w; unsigned int bytes = min(i->bytes, size); - int err = copy_to_user(buf, i->buf, bytes); - if (err) - return err; + if (copy_to_user(buf, i->buf, bytes)) + return -EFAULT; ret += bytes; buf += bytes; -- 2.20.1