Re: [syzbot] Re: [syzbot] [bpf?] [net?] KASAN: slab-use-after-free Read in bq_xmit_all

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Subject: Re: [syzbot] [bpf?] [net?] KASAN: slab-use-after-free Read in bq_xmit_all
Author: aha310510@gmail.com

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

---
 kernel/bpf/devmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 9e0e3b0a18e4..bca00badc0f8 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -465,7 +465,7 @@ static void bq_enqueue(struct net_device *dev, struct xdp_frame *xdpf,
 	 * Do the same with xdp_prog and flush_list since these fields
 	 * are only ever modified together.
 	 */
-	if (!bq->dev_rx) {
+	if (!bq->dev_rx && bq->count <= DEV_MAP_BULK_SIZE) {
 		struct list_head *flush_list = bpf_net_ctx_get_dev_flush_list();
 
 		bq->dev_rx = dev_rx;
--