[PATCH v2 1/9] libbpf: Introduce bpf_map_get_fd_by_id_flags()
From: Roberto Sassu
Date: Thu Jun 02 2022 - 10:38:20 EST
Introduce bpf_map_get_fd_by_id_flags(), to let a caller specify the open
flags needed for the operation. This could make an operation succeed, if
access to a map is restricted (i.e. it allows only certain operations).
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
---
tools/lib/bpf/bpf.c | 8 +++++++-
tools/lib/bpf/bpf.h | 1 +
tools/lib/bpf/libbpf.map | 1 +
3 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 240186aac8e6..33bac2006043 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -1047,18 +1047,24 @@ int bpf_prog_get_fd_by_id(__u32 id)
return libbpf_err_errno(fd);
}
-int bpf_map_get_fd_by_id(__u32 id)
+int bpf_map_get_fd_by_id_flags(__u32 id, __u32 flags)
{
union bpf_attr attr;
int fd;
memset(&attr, 0, sizeof(attr));
attr.map_id = id;
+ attr.open_flags = flags;
fd = sys_bpf_fd(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr));
return libbpf_err_errno(fd);
}
+int bpf_map_get_fd_by_id(__u32 id)
+{
+ return bpf_map_get_fd_by_id_flags(id, 0);
+}
+
int bpf_btf_get_fd_by_id(__u32 id)
{
union bpf_attr attr;
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index cabc03703e29..20e4c852362d 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -438,6 +438,7 @@ LIBBPF_API int bpf_map_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_btf_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_link_get_next_id(__u32 start_id, __u32 *next_id);
LIBBPF_API int bpf_prog_get_fd_by_id(__u32 id);
+LIBBPF_API int bpf_map_get_fd_by_id_flags(__u32 id, __u32 flags);
LIBBPF_API int bpf_map_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_btf_get_fd_by_id(__u32 id);
LIBBPF_API int bpf_link_get_fd_by_id(__u32 id);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 38e284ff057d..019278e66836 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -466,6 +466,7 @@ LIBBPF_1.0.0 {
libbpf_bpf_link_type_str;
libbpf_bpf_map_type_str;
libbpf_bpf_prog_type_str;
+ bpf_map_get_fd_by_id_flags;
local: *;
};
--
2.25.1