diff options
| author | Hou Tao <houtao1@huawei.com> | 2023-10-21 09:49:59 +0800 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2023-10-26 14:23:33 +0200 |
| commit | c421c12586b3f00fb96b5c9af15c9a051a9090b1 (patch) | |
| tree | 93527c11d4684d0c5dc602a575bd7dc90d2cf320 | |
| parent | 22360fad5889cbefe1eca695b0cc0273ab280b56 (diff) | |
bpf: Add more WARN_ON_ONCE checks for mismatched alloc and free
There are two possible mismatched alloc and free cases in BPF memory
allocator:
1) allocate from cache X but free by cache Y with a different unit_size
2) allocate from per-cpu cache but free by kmalloc cache or vice versa
So add more WARN_ON_ONCE checks in free_bulk() and __free_by_rcu() to
spot these mismatched alloc and free early.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20231021014959.3563841-1-houtao@huaweicloud.com
| -rw-r--r-- | kernel/bpf/memalloc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 5308e386380a..63b909d277d4 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -340,6 +340,7 @@ static void free_bulk(struct bpf_mem_cache *c) int cnt; WARN_ON_ONCE(tgt->unit_size != c->unit_size); + WARN_ON_ONCE(tgt->percpu_size != c->percpu_size); do { inc_active(c, &flags); @@ -365,6 +366,9 @@ static void __free_by_rcu(struct rcu_head *head) struct bpf_mem_cache *tgt = c->tgt; struct llist_node *llnode; + WARN_ON_ONCE(tgt->unit_size != c->unit_size); + WARN_ON_ONCE(tgt->percpu_size != c->percpu_size); + llnode = llist_del_all(&c->waiting_for_gp); if (!llnode) goto out; |