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Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r--kernel/bpf/verifier.c36
1 files changed, 32 insertions, 4 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d8520095ca03..39d5710c68ad 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -28,6 +28,8 @@
#include <linux/cpumask.h>
#include <linux/bpf_mem_alloc.h>
#include <net/xdp.h>
+#include <linux/trace_events.h>
+#include <linux/kallsyms.h>
#include "disasm.h"
@@ -21154,11 +21156,13 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
{
bool prog_extension = prog->type == BPF_PROG_TYPE_EXT;
bool prog_tracing = prog->type == BPF_PROG_TYPE_TRACING;
+ char trace_symbol[KSYM_SYMBOL_LEN];
const char prefix[] = "btf_trace_";
+ struct bpf_raw_event_map *btp;
int ret = 0, subprog = -1, i;
const struct btf_type *t;
bool conservative = true;
- const char *tname;
+ const char *tname, *fname;
struct btf *btf;
long addr = 0;
struct module *mod = NULL;
@@ -21289,10 +21293,34 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
return -EINVAL;
}
tname += sizeof(prefix) - 1;
- t = btf_type_by_id(btf, t->type);
- if (!btf_type_is_ptr(t))
- /* should never happen in valid vmlinux build */
+
+ /* The func_proto of "btf_trace_##tname" is generated from typedef without argument
+ * names. Thus using bpf_raw_event_map to get argument names.
+ */
+ btp = bpf_get_raw_tracepoint(tname);
+ if (!btp)
return -EINVAL;
+ fname = kallsyms_lookup((unsigned long)btp->bpf_func, NULL, NULL, NULL,
+ trace_symbol);
+ bpf_put_raw_tracepoint(btp);
+
+ if (fname)
+ ret = btf_find_by_name_kind(btf, fname, BTF_KIND_FUNC);
+
+ if (!fname || ret < 0) {
+ bpf_log(log, "Cannot find btf of tracepoint template, fall back to %s%s.\n",
+ prefix, tname);
+ t = btf_type_by_id(btf, t->type);
+ if (!btf_type_is_ptr(t))
+ /* should never happen in valid vmlinux build */
+ return -EINVAL;
+ } else {
+ t = btf_type_by_id(btf, ret);
+ if (!btf_type_is_func(t))
+ /* should never happen in valid vmlinux build */
+ return -EINVAL;
+ }
+
t = btf_type_by_id(btf, t->type);
if (!btf_type_is_func_proto(t))
/* should never happen in valid vmlinux build */