From: Alexei Starovoitov <ast@xxxxxxxxxx>
bpf_sycall programs can be used directly by the kernel modules
to load programs and create maps via kernel skeleton.
. Export bpf_sys_bpf syscall wrapper to be used in kernel skeleton.
. Export bpf_map_get to be used in kernel skeleton.
. Allow prog_run cmd for bpf_syscall programs with recursion check.
. Enable link_create and raw_tp_open cmds.
Acked-by: Yonghong Song <yhs@xxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
kernel/bpf/syscall.c | 38 ++++++++++++++++++++++++++++++++++----
1 file changed, 34 insertions(+), 4 deletions(-)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 72ce1edde950..49f88b30662a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -985,6 +985,7 @@ struct bpf_map *bpf_map_get(u32 ufd)
return map;
}
+EXPORT_SYMBOL(bpf_map_get);
struct bpf_map *bpf_map_get_with_uref(u32 ufd)
{
@@ -4756,23 +4757,52 @@ static bool syscall_prog_is_valid_access(int off, int size,
return true;
}
-BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
+BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
{
+ struct bpf_prog * __maybe_unused prog;
+
switch (cmd) {
case BPF_MAP_CREATE:
case BPF_MAP_UPDATE_ELEM:
case BPF_MAP_FREEZE:
case BPF_PROG_LOAD:
case BPF_BTF_LOAD:
+ case BPF_LINK_CREATE:
+ case BPF_RAW_TRACEPOINT_OPEN:
break;
- /* case BPF_PROG_TEST_RUN:
- * is not part of this list to prevent recursive test_run
- */
+#ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */
+ case BPF_PROG_TEST_RUN:
+ if (attr->test.data_in || attr->test.data_out ||
+ attr->test.ctx_out || attr->test.duration ||
+ attr->test.repeat || attr->test.flags)
+ return -EINVAL;
+
+ prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL);
+ if (IS_ERR(prog))
+ return PTR_ERR(prog);
+
+ if (attr->test.ctx_size_in < prog->aux->max_ctx_offset ||
+ attr->test.ctx_size_in > U16_MAX) {
+ bpf_prog_put(prog);
+ return -EINVAL;
+ }
+
+ if (!__bpf_prog_enter_sleepable(prog)) {
+ /* recursion detected */
+ bpf_prog_put(prog);
+ return -EBUSY;
+ }
+ attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in);
+ __bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */);
+ bpf_prog_put(prog);
+ return 0;
+#endif
default:
return -EINVAL;
}
return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
}
+EXPORT_SYMBOL(bpf_sys_bpf);
static const struct bpf_func_proto bpf_sys_bpf_proto = {
.func = bpf_sys_bpf,
--
2.30.2
