Forwarded: Re: [syzbot] [kvm?] [net?] [virt?] WARNING in virtio_transport_send_pkt_info

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Subject: Re: [syzbot] [kvm?] [net?] [virt?] WARNING in virtio_transport_send_pkt_info
Author: mst@xxxxxxxxxx


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


diff --git a/net/core/datagram.c b/net/core/datagram.c
index 94cc4705e91d..ab890448f3a2 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -642,6 +642,7 @@ int zerocopy_fill_skb_from_iter(struct sk_buff *skb,
 			return -EFAULT;
 
 		length -= copied;
+		iov_iter_advance(from, copied);
 
 		skb->data_len += copied;
 		skb->len += copied;