add bpf_map_def support for setting uid/gid/mode
Test: build, atest, adb shell ls -lZ /sys/fs/bpf
Bug: 149434314
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ie4001fbe16b4bc84fc8ec7138ae4928cd86f5ce7
diff --git a/libbpf_android/Loader.cpp b/libbpf_android/Loader.cpp
index 18dabba..1c27f9e 100644
--- a/libbpf_android/Loader.cpp
+++ b/libbpf_android/Loader.cpp
@@ -24,6 +24,7 @@
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <sys/stat.h>
#include <sys/utsname.h>
#include <unistd.h>
@@ -411,7 +412,11 @@
if (!reuse) {
ret = bpf_obj_pin(fd, mapPinLoc.c_str());
- if (ret < 0) return ret;
+ if (ret) return -errno;
+ ret = chown(mapPinLoc.c_str(), (uid_t)md[i].uid, (gid_t)md[i].gid);
+ if (ret) return -errno;
+ ret = chmod(mapPinLoc.c_str(), md[i].mode);
+ if (ret) return -errno;
}
mapFds.push_back(std::move(fd));
diff --git a/progs/include/bpf_helpers.h b/progs/include/bpf_helpers.h
index 825947f..ac08649 100644
--- a/progs/include/bpf_helpers.h
+++ b/progs/include/bpf_helpers.h
@@ -53,16 +53,16 @@
const void* key) = (void*)BPF_FUNC_map_delete_elem;
/* type safe macro to declare a map and related accessor functions */
-#define DEFINE_BPF_MAP_NO_ACCESSORS(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries) \
- const struct bpf_map_def SEC("maps") the_map = { \
- .type = BPF_MAP_TYPE_##TYPE, \
- .key_size = sizeof(TypeOfKey), \
- .value_size = sizeof(TypeOfValue), \
- .max_entries = (num_entries), \
- };
-
-#define DEFINE_BPF_MAP(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries) \
- DEFINE_BPF_MAP_NO_ACCESSORS(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries) \
+#define DEFINE_BPF_MAP_UGM(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries, usr, grp, md) \
+ const struct bpf_map_def SEC("maps") the_map = { \
+ .type = BPF_MAP_TYPE_##TYPE, \
+ .key_size = sizeof(TypeOfKey), \
+ .value_size = sizeof(TypeOfValue), \
+ .max_entries = (num_entries), \
+ .uid = (usr), \
+ .gid = (grp), \
+ .mode = (md), \
+ }; \
\
static inline __always_inline __unused TypeOfValue* bpf_##the_map##_lookup_elem( \
const TypeOfKey* k) { \
@@ -78,6 +78,15 @@
return bpf_map_delete_elem_unsafe(&the_map, k); \
};
+#define DEFINE_BPF_MAP(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries) \
+ DEFINE_BPF_MAP_UGM(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries, AID_ROOT, AID_ROOT, 0600)
+
+#define DEFINE_BPF_MAP_GRO(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries, gid) \
+ DEFINE_BPF_MAP_UGM(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries, AID_ROOT, gid, 0640)
+
+#define DEFINE_BPF_MAP_GRW(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries, gid) \
+ DEFINE_BPF_MAP_UGM(the_map, TYPE, TypeOfKey, TypeOfValue, num_entries, AID_ROOT, gid, 0660)
+
static int (*bpf_probe_read)(void* dst, int size, void* unsafe_ptr) = (void*) BPF_FUNC_probe_read;
static int (*bpf_probe_read_str)(void* dst, int size, void* unsafe_ptr) = (void*) BPF_FUNC_probe_read_str;
static unsigned long long (*bpf_ktime_get_ns)(void) = (void*) BPF_FUNC_ktime_get_ns;
diff --git a/progs/include/bpf_map_def.h b/progs/include/bpf_map_def.h
index 89a96d4..b233dc9 100644
--- a/progs/include/bpf_map_def.h
+++ b/progs/include/bpf_map_def.h
@@ -62,4 +62,8 @@
// The following are not supported by the Android bpfloader:
// unsigned int inner_map_idx;
// unsigned int numa_node;
+
+ unsigned int uid; // uid_t
+ unsigned int gid; // gid_t
+ unsigned int mode; // mode_t
};