| Message ID | 20190503123948.GD29695@mwanda |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net] net: atm: clean up a range check | expand |
From: Dan Carpenter <dan.carpenter@oracle.com> Date: Fri, 3 May 2019 15:39:48 +0300 > The code works fine but the problem is that check for negatives is a > no-op: > > if (arg < 0) > i = 0; > > The "i" value isn't used. We immediately overwrite it with: > > i = array_index_nospec(arg, MAX_LEC_ITF); > > The array_index_nospec() macro returns zero if "arg" is out of bounds so > this works, but the dead code is confusing and it doesn't look very > intentional. > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > --- > This applies to net, but it's just a clean up. I'm applying this to net-next, thanks Dan.
diff --git a/net/atm/lec.c b/net/atm/lec.c index ad4f829193f0..a0311493b01b 100644 --- a/net/atm/lec.c +++ b/net/atm/lec.c @@ -726,9 +726,7 @@ static int lecd_attach(struct atm_vcc *vcc, int arg) struct lec_priv *priv; if (arg < 0) - i = 0; - else - i = arg; + arg = 0; if (arg >= MAX_LEC_ITF) return -EINVAL; i = array_index_nospec(arg, MAX_LEC_ITF);
The code works fine but the problem is that check for negatives is a no-op: if (arg < 0) i = 0; The "i" value isn't used. We immediately overwrite it with: i = array_index_nospec(arg, MAX_LEC_ITF); The array_index_nospec() macro returns zero if "arg" is out of bounds so this works, but the dead code is confusing and it doesn't look very intentional. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- This applies to net, but it's just a clean up. net/atm/lec.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)