| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20260119-skb-meta-bpf-emit-call-from-prologue-v1-2-e8b88d6430d8@cloudflare.com>
Date: Mon, 19 Jan 2026 20:53:52 +0100
From: Jakub Sitnicki <jakub@...udflare.com>
To: bpf@...r.kernel.org
Cc: Alexei Starovoitov <ast@...nel.org>,
Daniel Borkmann <daniel@...earbox.net>,
John Fastabend <john.fastabend@...il.com>,
Andrii Nakryiko <andrii@...nel.org>,
Martin KaFai Lau <martin.lau@...ux.dev>,
Eduard Zingerman <eddyz87@...il.com>, Song Liu <song@...nel.org>,
Yonghong Song <yonghong.song@...ux.dev>, KP Singh <kpsingh@...nel.org>,
Stanislav Fomichev <sdf@...ichev.me>, Hao Luo <haoluo@...gle.com>,
Jiri Olsa <jolsa@...nel.org>, Amery Hung <ameryhung@...il.com>,
netdev@...r.kernel.org, kernel-team@...udflare.com
Subject: [PATCH bpf-next 2/4] bpf: net_sched: Use direct helper calls
instead of kfuncs in pro/epilogue
Convert bpf_qdisc prologue and epilogue to use BPF_EMIT_CALL for direct
helper calls instead of BPF_CALL_KFUNC.
Remove the BTF_ID_LIST entries for these functions since they are no longer
registered as kfuncs.
Signed-off-by: Jakub Sitnicki <jakub@...udflare.com>
---
net/sched/bpf_qdisc.c | 76 ++++++++++++++++++++++++---------------------------
1 file changed, 35 insertions(+), 41 deletions(-)
diff --git a/net/sched/bpf_qdisc.c b/net/sched/bpf_qdisc.c
index 098ca02aed89..cad9701d3b95 100644
--- a/net/sched/bpf_qdisc.c
+++ b/net/sched/bpf_qdisc.c
@@ -130,7 +130,30 @@ static int bpf_qdisc_btf_struct_access(struct bpf_verifier_log *log,
return 0;
}
-BTF_ID_LIST_SINGLE(bpf_qdisc_init_prologue_ids, func, bpf_qdisc_init_prologue)
+/* bpf_qdisc_init_prologue - Called in prologue of .init. */
+BPF_CALL_2(bpf_qdisc_init_prologue, struct Qdisc *, sch,
+ struct netlink_ext_ack *, extack)
+{
+ struct bpf_sched_data *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct Qdisc *p;
+
+ qdisc_watchdog_init(&q->watchdog, sch);
+
+ if (sch->parent != TC_H_ROOT) {
+ /* If qdisc_lookup() returns NULL, it means .init is called by
+ * qdisc_create_dflt() in mq/mqprio_init and the parent qdisc
+ * has not been added to qdisc_hash yet.
+ */
+ p = qdisc_lookup(dev, TC_H_MAJ(sch->parent));
+ if (p && !(p->flags & TCQ_F_MQROOT)) {
+ NL_SET_ERR_MSG(extack, "BPF qdisc only supported on root or mq");
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
static int bpf_qdisc_gen_prologue(struct bpf_insn *insn_buf, bool direct_write,
const struct bpf_prog *prog)
@@ -151,7 +174,7 @@ static int bpf_qdisc_gen_prologue(struct bpf_insn *insn_buf, bool direct_write,
*insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
*insn++ = BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_1, 16);
*insn++ = BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0);
- *insn++ = BPF_CALL_KFUNC(0, bpf_qdisc_init_prologue_ids[0]);
+ *insn++ = BPF_EMIT_CALL(bpf_qdisc_init_prologue);
*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1);
*insn++ = BPF_EXIT_INSN();
*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
@@ -160,7 +183,15 @@ static int bpf_qdisc_gen_prologue(struct bpf_insn *insn_buf, bool direct_write,
return insn - insn_buf;
}
-BTF_ID_LIST_SINGLE(bpf_qdisc_reset_destroy_epilogue_ids, func, bpf_qdisc_reset_destroy_epilogue)
+/* bpf_qdisc_reset_destroy_epilogue - Called in epilogue of .reset and .destroy */
+BPF_CALL_1(bpf_qdisc_reset_destroy_epilogue, struct Qdisc *, sch)
+{
+ struct bpf_sched_data *q = qdisc_priv(sch);
+
+ qdisc_watchdog_cancel(&q->watchdog);
+
+ return 0;
+}
static int bpf_qdisc_gen_epilogue(struct bpf_insn *insn_buf, const struct bpf_prog *prog,
s16 ctx_stack_off)
@@ -178,7 +209,7 @@ static int bpf_qdisc_gen_epilogue(struct bpf_insn *insn_buf, const struct bpf_pr
*/
*insn++ = BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_FP, ctx_stack_off);
*insn++ = BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0);
- *insn++ = BPF_CALL_KFUNC(0, bpf_qdisc_reset_destroy_epilogue_ids[0]);
+ *insn++ = BPF_EMIT_CALL(bpf_qdisc_reset_destroy_epilogue);
*insn++ = BPF_EXIT_INSN();
return insn - insn_buf;
@@ -230,41 +261,6 @@ __bpf_kfunc void bpf_qdisc_watchdog_schedule(struct Qdisc *sch, u64 expire, u64
qdisc_watchdog_schedule_range_ns(&q->watchdog, expire, delta_ns);
}
-/* bpf_qdisc_init_prologue - Hidden kfunc called in prologue of .init. */
-__bpf_kfunc int bpf_qdisc_init_prologue(struct Qdisc *sch,
- struct netlink_ext_ack *extack)
-{
- struct bpf_sched_data *q = qdisc_priv(sch);
- struct net_device *dev = qdisc_dev(sch);
- struct Qdisc *p;
-
- qdisc_watchdog_init(&q->watchdog, sch);
-
- if (sch->parent != TC_H_ROOT) {
- /* If qdisc_lookup() returns NULL, it means .init is called by
- * qdisc_create_dflt() in mq/mqprio_init and the parent qdisc
- * has not been added to qdisc_hash yet.
- */
- p = qdisc_lookup(dev, TC_H_MAJ(sch->parent));
- if (p && !(p->flags & TCQ_F_MQROOT)) {
- NL_SET_ERR_MSG(extack, "BPF qdisc only supported on root or mq");
- return -EINVAL;
- }
- }
-
- return 0;
-}
-
-/* bpf_qdisc_reset_destroy_epilogue - Hidden kfunc called in epilogue of .reset
- * and .destroy
- */
-__bpf_kfunc void bpf_qdisc_reset_destroy_epilogue(struct Qdisc *sch)
-{
- struct bpf_sched_data *q = qdisc_priv(sch);
-
- qdisc_watchdog_cancel(&q->watchdog);
-}
-
/* bpf_qdisc_bstats_update - Update Qdisc basic statistics
* @sch: The qdisc from which an skb is dequeued.
* @skb: The skb to be dequeued.
@@ -282,8 +278,6 @@ BTF_ID_FLAGS(func, bpf_kfree_skb, KF_RELEASE)
BTF_ID_FLAGS(func, bpf_qdisc_skb_drop, KF_RELEASE)
BTF_ID_FLAGS(func, bpf_dynptr_from_skb)
BTF_ID_FLAGS(func, bpf_qdisc_watchdog_schedule)
-BTF_ID_FLAGS(func, bpf_qdisc_init_prologue)
-BTF_ID_FLAGS(func, bpf_qdisc_reset_destroy_epilogue)
BTF_ID_FLAGS(func, bpf_qdisc_bstats_update)
BTF_KFUNCS_END(qdisc_kfunc_ids)
--
2.43.0
Powered by blists - more mailing lists