bpf: bpf_prog_array_copy() should return -ENOENT if exclude_prog not found

This makes is it possible for bpf prog detach to return -ENOENT.

Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Sean Young 2018-05-27 12:24:08 +01:00 committed by Daniel Borkmann
parent 9ce64f192d
commit 170a7e3ea0
2 changed files with 11 additions and 2 deletions

View File

@ -1616,6 +1616,7 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
int new_prog_cnt, carry_prog_cnt = 0;
struct bpf_prog **existing_prog;
struct bpf_prog_array *array;
bool found_exclude = false;
int new_prog_idx = 0;
/* Figure out how many existing progs we need to carry over to
@ -1624,14 +1625,20 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
if (old_array) {
existing_prog = old_array->progs;
for (; *existing_prog; existing_prog++) {
if (*existing_prog != exclude_prog &&
*existing_prog != &dummy_bpf_prog.prog)
if (*existing_prog == exclude_prog) {
found_exclude = true;
continue;
}
if (*existing_prog != &dummy_bpf_prog.prog)
carry_prog_cnt++;
if (*existing_prog == include_prog)
return -EEXIST;
}
}
if (exclude_prog && !found_exclude)
return -ENOENT;
/* How many progs (not NULL) will be in the new array? */
new_prog_cnt = carry_prog_cnt;
if (include_prog)

View File

@ -1006,6 +1006,8 @@ void perf_event_detach_bpf_prog(struct perf_event *event)
old_array = event->tp_event->prog_array;
ret = bpf_prog_array_copy(old_array, event->prog, NULL, &new_array);
if (ret == -ENOENT)
goto unlock;
if (ret < 0) {
bpf_prog_array_delete_safe(old_array, event->prog);
} else {