Thread (13 messages) flat view 13 messages, 4 authors, 2025-11-26
STALE265d

[PATCH bpf-next v3 2/4] bpf: net_sched: Use the correct destructor kfunc type

From: Sami Tolvanen <samitolvanen@google.com>
Date: 2025-07-28 20:27:05
Also in: bpf, lkml
Subsystem: networking [general], tc subsystem, the rest · Maintainers: "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds

With CONFIG_CFI_CLANG enabled, the kernel strictly enforces that
indirect function calls use a function pointer type that matches
the target function. As bpf_kfree_skb() signature differs from the
btf_dtor_kfunc_t pointer type used for the destructor calls in
bpf_obj_free_fields(), add a stub function with the correct type to
fix the type mismatch.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
 net/sched/bpf_qdisc.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/net/sched/bpf_qdisc.c b/net/sched/bpf_qdisc.c
index adcb618a2bfc..e9bea9890777 100644
--- a/net/sched/bpf_qdisc.c
+++ b/net/sched/bpf_qdisc.c
@@ -202,6 +202,12 @@ __bpf_kfunc void bpf_kfree_skb(struct sk_buff *skb)
 	kfree_skb(skb);
 }
 
+__bpf_kfunc void bpf_kfree_skb_dtor(void *skb)
+{
+	bpf_kfree_skb(skb);
+}
+CFI_NOSEAL(bpf_kfree_skb_dtor);
+
 /* bpf_qdisc_skb_drop - Drop an skb by adding it to a deferred free list.
  * @skb: The skb whose reference to be released and dropped.
  * @to_free_list: The list of skbs to be dropped.
@@ -449,7 +455,7 @@ static struct bpf_struct_ops bpf_Qdisc_ops = {
 	.owner = THIS_MODULE,
 };
 
-BTF_ID_LIST_SINGLE(bpf_sk_buff_dtor_ids, func, bpf_kfree_skb)
+BTF_ID_LIST_SINGLE(bpf_sk_buff_dtor_ids, func, bpf_kfree_skb_dtor)
 
 static int __init bpf_qdisc_kfunc_init(void)
 {
-- 
2.50.1.552.g942d659e1b-goog
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help