[PATCH net 08/14] can: skb: make echo skb freeing safe in any IRQ context
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2026-08-26 12:10:48
Also in:
linux-can
Subsystem:
can network drivers, can network layer, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Oliver Hartkopp, Linus Torvalds
From: Cunhao Lu <redacted> can_put_echo_skb() can be called with hardware interrupts disabled. Its direct drop paths use kfree_skb(), while can_create_echo_skb() uses kfree_skb() when cloning fails and consume_skb() after a successful clone. None of these helpers is safe in every IRQ context. Use dev_kfree_skb_any() for all drop paths and dev_consume_skb_any() when consuming a successfully cloned skb. This preserves the respective skb drop and consumed semantics regardless of the caller IRQ context. Signed-off-by: Cunhao Lu <redacted> Link: https://patch.msgid.link/tencent_E84809CF236D0137885E7E4E4D58340B3208@qq.com Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/can/dev/skb.c | 4 ++-- include/linux/can/skb.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c
index 4f7a189de265..0ed8057a3cb2 100644
--- a/drivers/net/can/dev/skb.c
+++ b/drivers/net/can/dev/skb.c@@ -63,7 +63,7 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, (skb->protocol != htons(ETH_P_CAN) && skb->protocol != htons(ETH_P_CANFD) && skb->protocol != htons(ETH_P_CANXL))) { - kfree_skb(skb); + dev_kfree_skb_any(skb); return 0; }
@@ -91,7 +91,7 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, } else { /* locking problem with netif_stop_queue() ?? */ netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx); - kfree_skb(skb); + dev_kfree_skb_any(skb); return -EBUSY; }
diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h
index a70a02967071..78c5870e2f9a 100644
--- a/include/linux/can/skb.h
+++ b/include/linux/can/skb.h@@ -76,12 +76,12 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb) nskb = skb_clone(skb, GFP_ATOMIC); if (unlikely(!nskb)) { - kfree_skb(skb); + dev_kfree_skb_any(skb); return NULL; } can_skb_set_owner(nskb, skb->sk); - consume_skb(skb); + dev_consume_skb_any(skb); return nskb; }
--
2.53.0