This is a note to let you know that I've just added the patch titled
bpf: refactor bpf_helper_changes_pkt_data to use helper number
to the 6.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bpf-refactor-bpf_helper_changes_pkt_data-to-use-help.patch
and it can be found in the queue-6.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 902b683d7eab7703b8d9968e37971d32bd58c144
Author: Eduard Zingerman <eddyz87@xxxxxxxxx>
Date: Mon Dec 9 20:10:54 2024 -0800
bpf: refactor bpf_helper_changes_pkt_data to use helper number
[ Upstream commit b238e187b4a2d3b54d80aec05a9cab6466b79dde ]
Use BPF helper number instead of function pointer in
bpf_helper_changes_pkt_data(). This would simplify usage of this
function in verifier.c:check_cfg() (in a follow-up patch),
where only helper number is easily available and there is no real need
to lookup helper proto.
Signed-off-by: Eduard Zingerman <eddyz87@xxxxxxxxx>
Link: https://lore.kernel.org/r/20241210041100.1898468-3-eddyz87@xxxxxxxxx
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Stable-dep-of: 1a4607ffba35 ("bpf: consider that tail calls invalidate packet pointers")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 7d7578a8eac1..5118caf8aa1c 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1121,7 +1121,7 @@ bool bpf_jit_supports_arena(void);
bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena);
u64 bpf_arch_uaddress_limit(void);
void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie);
-bool bpf_helper_changes_pkt_data(void *func);
+bool bpf_helper_changes_pkt_data(enum bpf_func_id func_id);
static inline bool bpf_dump_raw_ok(const struct cred *cred)
{
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 3af5f42ea791..2b9c8c168a0b 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -2940,7 +2940,7 @@ void __weak bpf_jit_compile(struct bpf_prog *prog)
{
}
-bool __weak bpf_helper_changes_pkt_data(void *func)
+bool __weak bpf_helper_changes_pkt_data(enum bpf_func_id func_id)
{
return false;
}
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 767f1cb8c27e..a0cab0d0252f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -10476,7 +10476,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn
}
/* With LD_ABS/IND some JITs save/restore skb from r1. */
- changes_data = bpf_helper_changes_pkt_data(fn->func);
+ changes_data = bpf_helper_changes_pkt_data(func_id);
if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) {
verbose(env, "kernel subsystem misconfigured func %s#%d: r1 != ctx\n",
func_id_name(func_id), func_id);
diff --git a/net/core/filter.c b/net/core/filter.c
index 55495063621d..4b0ad74cfff5 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -7918,42 +7918,35 @@ static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv6_proto = {
#endif /* CONFIG_INET */
-bool bpf_helper_changes_pkt_data(void *func)
-{
- if (func == bpf_skb_vlan_push ||
- func == bpf_skb_vlan_pop ||
- func == bpf_skb_store_bytes ||
- func == bpf_skb_change_proto ||
- func == bpf_skb_change_head ||
- func == sk_skb_change_head ||
- func == bpf_skb_change_tail ||
- func == sk_skb_change_tail ||
- func == bpf_skb_adjust_room ||
- func == sk_skb_adjust_room ||
- func == bpf_skb_pull_data ||
- func == sk_skb_pull_data ||
- func == bpf_clone_redirect ||
- func == bpf_l3_csum_replace ||
- func == bpf_l4_csum_replace ||
- func == bpf_xdp_adjust_head ||
- func == bpf_xdp_adjust_meta ||
- func == bpf_msg_pull_data ||
- func == bpf_msg_push_data ||
- func == bpf_msg_pop_data ||
- func == bpf_xdp_adjust_tail ||
-#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
- func == bpf_lwt_seg6_store_bytes ||
- func == bpf_lwt_seg6_adjust_srh ||
- func == bpf_lwt_seg6_action ||
-#endif
-#ifdef CONFIG_INET
- func == bpf_sock_ops_store_hdr_opt ||
-#endif
- func == bpf_lwt_in_push_encap ||
- func == bpf_lwt_xmit_push_encap)
+bool bpf_helper_changes_pkt_data(enum bpf_func_id func_id)
+{
+ switch (func_id) {
+ case BPF_FUNC_clone_redirect:
+ case BPF_FUNC_l3_csum_replace:
+ case BPF_FUNC_l4_csum_replace:
+ case BPF_FUNC_lwt_push_encap:
+ case BPF_FUNC_lwt_seg6_action:
+ case BPF_FUNC_lwt_seg6_adjust_srh:
+ case BPF_FUNC_lwt_seg6_store_bytes:
+ case BPF_FUNC_msg_pop_data:
+ case BPF_FUNC_msg_pull_data:
+ case BPF_FUNC_msg_push_data:
+ case BPF_FUNC_skb_adjust_room:
+ case BPF_FUNC_skb_change_head:
+ case BPF_FUNC_skb_change_proto:
+ case BPF_FUNC_skb_change_tail:
+ case BPF_FUNC_skb_pull_data:
+ case BPF_FUNC_skb_store_bytes:
+ case BPF_FUNC_skb_vlan_pop:
+ case BPF_FUNC_skb_vlan_push:
+ case BPF_FUNC_store_hdr_opt:
+ case BPF_FUNC_xdp_adjust_head:
+ case BPF_FUNC_xdp_adjust_meta:
+ case BPF_FUNC_xdp_adjust_tail:
return true;
-
- return false;
+ default:
+ return false;
+ }
}
const struct bpf_func_proto bpf_event_output_data_proto __weak;
