From: Andrii Nakryiko <andriin@xxxxxx>
commit 62039c30c19dcab96621e074aeeb90da7100def7 upstream.
Local storage array isn't initialized, so if cgroup storage allocation fails
for BPF_CGROUP_STORAGE_SHARED, error handling code will attempt to free
uninitialized pointer for BPF_CGROUP_STORAGE_PERCPU storage type. Avoid this
by always initializing storage pointers to NULLs.
Fixes: 8bad74f9840f ("bpf: extend cgroup bpf core to allow multiple cgroup storage types")
Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Link: https://lore.kernel.org/bpf/20200309222756.1018737-1-andriin@xxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/bpf/cgroup.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -303,8 +303,8 @@ int __cgroup_bpf_attach(struct cgroup *c
{
struct list_head *progs = &cgrp->bpf.progs[type];
struct bpf_prog *old_prog = NULL;
- struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE],
- *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {NULL};
+ struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {};
+ struct bpf_cgroup_storage *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {};
enum bpf_cgroup_storage_type stype;
struct bpf_prog_list *pl;
bool pl_was_allocated;
