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@xxxxxxxxx

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

---
 kernel/bpf/devmap.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 9e0e3b0a18e4..5e2ee97ad09f 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -378,7 +378,9 @@ static void bq_xmit_all(struct xdp_dev_bulk_queue *bq, u32 flags)
 	int to_send = cnt;
 	int i;
 
-	if (unlikely(!cnt))
+	printk(KERN_INFO "bq->count = %u\n",cnt);
+
+	if (unlikely(!cnt) || unlikely(cnt) > DEV_MAP_BULK_SIZE)
 		return;
 
 	for (i = 0; i < cnt; i++) {
--