Re: [syzbot] Test for 5681e40d297b30f5b513

From: syzbot
Date: Sun May 12 2024 - 11:21:21 EST


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Subject: Test for 5681e40d297b30f5b513
Author: syoshida@xxxxxxxxxx

#syz test

diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c
index a6fb89fa6278..df01628c6509 100644
--- a/net/can/j1939/main.c
+++ b/net/can/j1939/main.c
@@ -344,6 +344,9 @@ int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb)
/* make it a full can frame again */
skb_put(skb, J1939_CAN_FTR + (8 - dlc));

+ /* initialize unused data */
+ memset(cf->data + dlc, 0, 8 - dlc);
+
canid = CAN_EFF_FLAG |
(skcb->priority << 26) |
(skcb->addr.pgn << 8) |