bpf_xdp_pull_data() may change packet data and therefore packet pointers
need to be invalidated. Add bpf_xdp_pull_data() to the special kfunc
list instead of introducing a new KF_ flag until there are more kfuncs
changing packet data.
Signed-off-by: Amery Hung <ameryhung@xxxxxxxxx>
---
kernel/bpf/verifier.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b9394f8fac0e..2355f2999773 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -12235,6 +12235,7 @@ enum special_kfunc_type {
KF_bpf_dynptr_from_skb,
KF_bpf_dynptr_from_xdp,
KF_bpf_dynptr_from_skb_meta,
+ KF_bpf_xdp_pull_data,
KF_bpf_dynptr_slice,
KF_bpf_dynptr_slice_rdwr,
KF_bpf_dynptr_clone,
@@ -12285,10 +12286,12 @@ BTF_ID(func, bpf_rbtree_right)
BTF_ID(func, bpf_dynptr_from_skb)
BTF_ID(func, bpf_dynptr_from_xdp)
BTF_ID(func, bpf_dynptr_from_skb_meta)
+BTF_ID(func, bpf_xdp_pull_data)
#else
BTF_ID_UNUSED
BTF_ID_UNUSED
BTF_ID_UNUSED
+BTF_ID_UNUSED
#endif
BTF_ID(func, bpf_dynptr_slice)
BTF_ID(func, bpf_dynptr_slice_rdwr)
@@ -12358,6 +12361,11 @@ static bool is_kfunc_bpf_preempt_enable(struct bpf_kfunc_call_arg_meta *meta)
return meta->func_id == special_kfunc_list[KF_bpf_preempt_enable];
}
+static bool is_kfunc_pkt_changing(struct bpf_kfunc_call_arg_meta *meta)
+{
+ return meta->func_id == special_kfunc_list[KF_bpf_xdp_pull_data];
+}
+
static enum kfunc_ptr_arg_type
get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,
struct bpf_kfunc_call_arg_meta *meta,
@@ -14077,6 +14085,9 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
}
}
+ if (is_kfunc_pkt_changing(&meta))
+ clear_all_pkt_pointers(env);
+
nargs = btf_type_vlen(meta.func_proto);
args = (const struct btf_param *)(meta.func_proto + 1);
for (i = 0; i < nargs; i++) {
@@ -17798,6 +17809,8 @@ static int visit_insn(int t, struct bpf_verifier_env *env)
*/
if (ret == 0 && is_kfunc_sleepable(&meta))
mark_subprog_might_sleep(env, t);
+ if (ret == 0 && is_kfunc_pkt_changing(&meta))
+ mark_subprog_changes_pkt_data(env, t);
}
return visit_func_call_insn(t, insns, env, insn->src_reg == BPF_PSEUDO_CALL);
--
2.47.3
