Ensure that registered destructor kfuncs have the same type
as btf_dtor_kfunc_t to avoid a kernel panic on systems with
CONFIG_CFI_CLANG enabled.
Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
Acked-by: Yonghong Song <yonghong.song@xxxxxxxxx>
---
kernel/bpf/btf.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 0aff814cb53a..2b0ebd46db4a 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -8856,6 +8856,13 @@ static int btf_check_dtor_kfuncs(struct btf *btf, const struct btf_id_dtor_kfunc
*/
if (!t || !btf_type_is_ptr(t))
return -EINVAL;
+
+ if (IS_ENABLED(CONFIG_CFI_CLANG)) {
+ /* Ensure the destructor kfunc type matches btf_dtor_kfunc_t */
+ t = btf_type_by_id(btf, t->type);
+ if (!btf_type_is_void(t))
+ return -EINVAL;
+ }
}
return 0;
}
--
2.50.1.552.g942d659e1b-goog
