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 <dan.carpenter@xxxxxxxxxx>
---
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
