Introduce bpf_obj_get_opts(), to let the caller pass the needed permissions
for the operation. Keep the existing bpf_obj_get() to request read-write
permissions.
bpf_obj_get() allows the caller to get a file descriptor from a pinned
object with the provided pathname. Specifying permissions has only effect
on maps (for links, the permission must be always read-write).
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
---
tools/lib/bpf/bpf.c | 12 +++++++++++-
tools/lib/bpf/bpf.h | 2 ++
tools/lib/bpf/libbpf.map | 1 +
3 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 5f2785a4c358..0df088890864 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -577,18 +577,28 @@ int bpf_obj_pin(int fd, const char *pathname)
return libbpf_err_errno(ret);
}
-int bpf_obj_get(const char *pathname)
+int bpf_obj_get_opts(const char *pathname,
+ const struct bpf_get_fd_opts *opts)
{
union bpf_attr attr;
int fd;
+ if (!OPTS_VALID(opts, bpf_get_fd_opts))
+ return libbpf_err(-EINVAL);
+
memset(&attr, 0, sizeof(attr));
attr.pathname = ptr_to_u64((void *)pathname);
+ attr.file_flags = OPTS_GET(opts, flags, 0);
fd = sys_bpf_fd(BPF_OBJ_GET, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
+int bpf_obj_get(const char *pathname)
+{
+ return bpf_obj_get_opts(pathname, NULL);
+}
+
int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
unsigned int flags)
{
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index b75fd9d37bad..e0c5018cc131 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -279,6 +279,8 @@ struct bpf_get_fd_opts {
};
#define bpf_get_fd_opts__last_field flags
+LIBBPF_API int bpf_obj_get_opts(const char *pathname,
+ const struct bpf_get_fd_opts *opts);
LIBBPF_API int bpf_obj_get(const char *pathname);
struct bpf_prog_attach_opts {
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index dba97d2ef8a9..55516b19e22f 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -368,4 +368,5 @@ LIBBPF_1.0.0 {
bpf_map_get_fd_by_id_opts;
bpf_btf_get_fd_by_id_opts;
bpf_link_get_fd_by_id_opts;
+ bpf_obj_get_opts;
};
--
2.25.1
