This is a note to let you know that I've just added the patch titled
bpf: Add missing btf_put to register_btf_id_dtor_kfuncs
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bpf-add-missing-btf_put-to-register_btf_id_dtor_kfun.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e979ec2158d753a572e5ee08b826b39d9896e306
Author: Jiri Olsa <jolsa@xxxxxxxxxx>
Date: Fri Jan 20 13:21:48 2023 +0100
bpf: Add missing btf_put to register_btf_id_dtor_kfuncs
[ 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@xxxxxxxxx>
Fixes: 5ce937d613a4 ("bpf: Populate pairs of btf_id and destructor kfunc in btf")
Acked-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230120122148.1522359-1-jolsa@xxxxxxxxxx
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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;
}
