From: Jiri Olsa jolsa@kernel.org
[ Upstream commit 74bc3a5acc82f020d2e126f56c535d02d1e74e37 ]
We take the BTF reference before we register dtors and we need to put it back when it's done.
We probably won't se a problem with kernel BTF, but module BTF would stay loaded (because of the extra ref) even when its module is removed.
Cc: Kumar Kartikeya Dwivedi memxor@gmail.com Fixes: 5ce937d613a4 ("bpf: Populate pairs of btf_id and destructor kfunc in btf") Acked-by: Kumar Kartikeya Dwivedi memxor@gmail.com Signed-off-by: Jiri Olsa jolsa@kernel.org Link: https://lore.kernel.org/r/20230120122148.1522359-1-jolsa@kernel.org Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/btf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index efdbba2a0230..a7c2f0c3fc19 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -7607,9 +7607,9 @@ int register_btf_id_dtor_kfuncs(const struct btf_id_dtor_kfunc *dtors, u32 add_c
sort(tab->dtors, tab->cnt, sizeof(tab->dtors[0]), btf_id_cmp_func, NULL);
- return 0; end: - btf_free_dtor_kfunc_tab(btf); + if (ret) + btf_free_dtor_kfunc_tab(btf); btf_put(btf); return ret; }