Re: [PATCH net 3/4] can: raw: instantly reject disabled CAN frames
From: Oliver Hartkopp <socketcan@hartkopp.net>
Date: 2026-01-15 07:58:50
Also in:
linux-can
Subsystem:
can network layer, the rest · Maintainers:
Oliver Hartkopp, Marc Kleine-Budde, Linus Torvalds
Hello Marc, On 14.01.26 11:45, Marc Kleine-Budde wrote:
From: Oliver Hartkopp <socketcan@hartkopp.net>
quoted hunk ↗ jump to hunk
@@ -944,6 +945,10 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) if (!dev) return -ENXIO; + /* no sending on a CAN device in read-only mode */ + if (can_cap_enabled(dev, CAN_CAP_RO)) + return -EACCES; + skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv), msg->msg_flags & MSG_DONTWAIT, &err); if (!skb)
At midnight the AI review from the netdev patchwork correctly identified a problem with the above code: https://netdev-ai.bots.linux.dev/ai-review.html?id=fb201338-eed0-488f-bb32-5240af254cf4 An excellent tool indeed! This patch has to be changed to not leak a dev reference. Can you please change it in your tree and send an updated PR? Sorry for that extra effort :-/ Best regards, Oliver
diff --git a/net/can/raw.c b/net/can/raw.c
index d66036da6753..12293363413c 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c@@ -944,12 +944,14 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
dev = dev_get_by_index(sock_net(sk), ifindex);
if (!dev)
return -ENXIO;
/* no sending on a CAN device in read-only mode */
- if (can_cap_enabled(dev, CAN_CAP_RO))
- return -EACCES;
+ if (can_cap_enabled(dev, CAN_CAP_RO)) {
+ err = -EACCES;
+ goto put_dev;
+ }
skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
msg->msg_flags & MSG_DONTWAIT, &err);
if (!skb)
goto put_dev;