Add 'priv_stack_allowed()' callback function in bpf_verifier_ops. If the
callback function returns true, the struct_ops are eligible to
use private stack. Otherwise, normal kernel stack is used.
Signed-off-by: Yonghong Song <yonghong.song@xxxxxxxxx>
---
include/linux/bpf.h | 1 +
kernel/bpf/verifier.c | 2 ++
2 files changed, 3 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 6ad8ace7075a..a789cd2f5d6a 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -988,6 +988,7 @@ struct bpf_verifier_ops {
int (*btf_struct_access)(struct bpf_verifier_log *log,
const struct bpf_reg_state *reg,
int off, int size);
+ bool (*priv_stack_allowed)(void);
};
struct bpf_prog_offload_ops {
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index a12f5e823284..a14857015ad4 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5995,6 +5995,8 @@ static bool bpf_enable_private_stack(struct bpf_verifier_env *env)
case BPF_PROG_TYPE_PERF_EVENT:
case BPF_PROG_TYPE_RAW_TRACEPOINT:
return true;
+ case BPF_PROG_TYPE_STRUCT_OPS:
+ return env->ops->priv_stack_allowed && env->ops->priv_stack_allowed();
case BPF_PROG_TYPE_TRACING:
if (env->prog->expected_attach_type != BPF_TRACE_ITER)
return true;
--
2.43.5
