netdev - [PATCH] can: janz-ican3: initialize dlc variable

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Date:   Sat,  8 Jan 2022 06:33:19 -0800
From:   trix@...hat.com
To:     wg@...ndegger.com, mkl@...gutronix.de, davem@...emloft.net,
        kuba@...nel.org, nathan@...nel.org, ndesaulniers@...gle.com,
        mailhol.vincent@...adoo.fr, stefan.maetje@....eu
Cc:     linux-can@...r.kernel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org, llvm@...ts.linux.dev,
        Tom Rix <trix@...hat.com>
Subject: [PATCH] can: janz-ican3: initialize dlc variable

From: Tom Rix <trix@...hat.com>

Clang static analysis reports this problem
janz-ican3.c:1311:2: warning: Undefined or garbage value returned to caller
        return dlc;
        ^~~~~~~~~~

dlc is only set with this conditional
	if (!(cf->can_id & CAN_RTR_FLAG))
		dlc = cf->len;

But is always returned.  So initialize dlc to 0.

Fixes: cc4b08c31b5c ("can: do not increase tx_bytes statistics for RTR frames")
Signed-off-by: Tom Rix <trix@...hat.com>
---
 drivers/net/can/janz-ican3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/janz-ican3.c b/drivers/net/can/janz-ican3.c
index 5b677af5f2a41..808c105cf8f7e 100644
--- a/drivers/net/can/janz-ican3.c
+++ b/drivers/net/can/janz-ican3.c
@@ -1285,7 +1285,7 @@ static unsigned int ican3_get_echo_skb(struct ican3_dev *mod)
 {
 	struct sk_buff *skb = skb_dequeue(&mod->echoq);
 	struct can_frame *cf;
-	u8 dlc;
+	u8 dlc = 0;
 
 	/* this should never trigger unless there is a driver bug */
 	if (!skb) {
-- 
2.26.3