[PATCH v3 2/3] can: skb: make CAN skb allocation failure paths IRQ-safe

Cunhao Lu <[email protected]> Fri, 31 Jul 2026 17:45:01 +0800
Newsgroups org.kernel.vger.linux-can,org.kernel.vger.linux-kernel,org.kernel.vger.stable
Message-ID <[email protected]>
The CAN skb allocation helpers are used from hardware interrupt receive
handlers. If can_skb_ext_add() fails, they release the newly allocated skb
with kfree_skb(), which is not safe in hardware interrupt context.

Use dev_kfree_skb_any() for the allocation failure paths in
alloc_can_skb(), alloc_canfd_skb(), and alloc_canxl_skb().

Fixes: 96ea3a1e2d31 ("can: add CAN skb extension infrastructure")
Cc: [email protected]
Signed-off-by: Cunhao Lu <[email protected]>
---
 drivers/net/can/dev/skb.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c
index d7b5a5d17ff2..d34d3e7d4c9f 100644
--- a/drivers/net/can/dev/skb.c
+++ b/drivers/net/can/dev/skb.c
@@ -223,7 +223,7 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
 
 	csx = can_skb_ext_add(skb);
 	if (!csx) {
-		kfree_skb(skb);
+		dev_kfree_skb_any(skb);
 		goto out_error_cc;
 	}
 
@@ -254,7 +254,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev,
 
 	csx = can_skb_ext_add(skb);
 	if (!csx) {
-		kfree_skb(skb);
+		dev_kfree_skb_any(skb);
 		goto out_error_fd;
 	}
 
@@ -292,7 +292,7 @@ struct sk_buff *alloc_canxl_skb(struct net_device *dev,
 
 	csx = can_skb_ext_add(skb);
 	if (!csx) {
-		kfree_skb(skb);
+		dev_kfree_skb_any(skb);
 		goto out_error_xl;
 	}
 

-- 
2.34.1