Re: [PATCH][next] net: mvpp2: cls: fix less than zero check on a u32 variable

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

Hi Colin,

On Sun,  5 May 2019 22:38:14 +0100
Colin King <colin.king@canonical.com> wrote:

>From: Colin Ian King <colin.king@canonical.com>
>
>The signed return from the call to mvpp2_cls_c2_port_flow_index is being
>assigned to the u32 variable c2.index and then checked for a negative
>error condition which is always going to be false. Fix this by assigning
>the return to the int variable index and checking this instead.
>
>Addresses-Coverity: ("Unsigned compared against 0")
>Fixes: 90b509b39ac9 ("net: mvpp2: cls: Add Classification offload support")
>Signed-off-by: Colin Ian King <colin.king@canonical.com>
>---
> drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c
>index 4989fb13244f..c10bc257f571 100644
>--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c
>+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c
>@@ -1029,12 +1029,14 @@ static int mvpp2_port_c2_tcam_rule_add(struct mvpp2_port *port,
> 	struct flow_action_entry *act;
> 	struct mvpp2_cls_c2_entry c2;
> 	u8 qh, ql, pmap;
>+	int index;
> 
> 	memset(&c2, 0, sizeof(c2));
> 
>-	c2.index = mvpp2_cls_c2_port_flow_index(port, rule->loc);
>-	if (c2.index < 0)
>+	index = mvpp2_cls_c2_port_flow_index(port, rule->loc);
>+	if (index < 0)
> 		return -EINVAL;
>+	c2.index = index;
> 
> 	act = &rule->flow->action.entries[0];
> 

Thanks for the fix, my bad.

Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>

Maxime