diff options
Diffstat (limited to 'kernel/bpf/trampoline.c')
| -rw-r--r-- | kernel/bpf/trampoline.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index f30bca2a4d01..9be85aa4ec5f 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -6,6 +6,7 @@ #include <linux/ftrace.h> #include <linux/rbtree_latch.h> #include <linux/perf_event.h> +#include <linux/btf.h> /* dummy _ops. The verifier will operate on target program's ops. */ const struct bpf_verifier_ops bpf_extension_verifier_ops = { @@ -233,15 +234,23 @@ out: return err; } -static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(enum bpf_attach_type t) +static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog) { - switch (t) { + switch (prog->expected_attach_type) { case BPF_TRACE_FENTRY: return BPF_TRAMP_FENTRY; case BPF_MODIFY_RETURN: return BPF_TRAMP_MODIFY_RETURN; case BPF_TRACE_FEXIT: return BPF_TRAMP_FEXIT; + case BPF_LSM_MAC: + if (!prog->aux->attach_func_proto->type) + /* The function returns void, we cannot modify its + * return value. + */ + return BPF_TRAMP_FEXIT; + else + return BPF_TRAMP_MODIFY_RETURN; default: return BPF_TRAMP_REPLACE; } @@ -255,7 +264,7 @@ int bpf_trampoline_link_prog(struct bpf_prog *prog) int cnt; tr = prog->aux->trampoline; - kind = bpf_attach_type_to_tramp(prog->expected_attach_type); + kind = bpf_attach_type_to_tramp(prog); mutex_lock(&tr->mutex); if (tr->extension_prog) { /* cannot attach fentry/fexit if extension prog is attached. @@ -305,7 +314,7 @@ int bpf_trampoline_unlink_prog(struct bpf_prog *prog) int err; tr = prog->aux->trampoline; - kind = bpf_attach_type_to_tramp(prog->expected_attach_type); + kind = bpf_attach_type_to_tramp(prog); mutex_lock(&tr->mutex); if (kind == BPF_TRAMP_REPLACE) { WARN_ON_ONCE(!tr->extension_prog); |