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From:   Vincent Mailhol <mailhol.vincent@wanadoo.fr>
To:     Marc Kleine-Budde <mkl@pengutronix.de>, linux-can@vger.kernel.org
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Oliver Hartkopp <socketcan@hartkopp.net>,
        Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Subject: [PATCH v2 1/2] can: netlink: remove redundant check in can_validate()
Date:   Fri,  4 Jun 2021 00:15:49 +0900
Message-Id: <20210603151550.140727-2-mailhol.vincent@wanadoo.fr>
In-Reply-To: <20210603151550.140727-1-mailhol.vincent@wanadoo.fr>
References: <20210603151550.140727-1-mailhol.vincent@wanadoo.fr>
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can_validate() does a first check:
|	if (is_can_fd) {
|		if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
|			return -EOPNOTSUPP;
|	}

If that first if succeeds, we know that if is_can_fd is true then
data[IFLA_CAN_BITTIMING is set.

However, the next if switch does not leverage on above knowledge and
redoes the check:
| 	if (data[IFLA_CAN_DATA_BITTIMING]) {
|		if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
|		                   ^~~~~~~~~~~~~~~~~~~~~~~~
| 			return -EOPNOTSUPP;
| 	}

This patch removes that redundant check.

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
---
 drivers/net/can/dev/netlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index e38c2566aff4..32c603a09809 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -47,7 +47,7 @@ static int can_validate(struct nlattr *tb[], struct nlattr *data[],
 	}
 
 	if (data[IFLA_CAN_DATA_BITTIMING]) {
-		if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
+		if (!is_can_fd)
 			return -EOPNOTSUPP;
 	}
 
-- 
2.31.1