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From: Stefan Baranoff <sbaranoff@gmail.com>
Date: Fri, 20 Aug 2021 14:18:20 -0400
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Subject: [dpdk-dev] i40evf: potential segfault
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Hi all!

I was chasing a potential segfault and it appears, if I'm reading this
driver correctly, that in i40evf_init_vf() the value vf->adapter->eth_dev
is never set like pf->adapter->eth_dev is in eth_i40e_dev_init().

I believe this is leading to a segfault when something like
i40e_recv_scattered_pkts calls:
dev = I40E_VSI_TO_ETH_DEV(rxq->vsi); // dev ends up NULL here
dev->data->rx_mbuf_alloc_failed++; // this generates a NULL pointer
dereference/segfault


I'm not completely confident in my understanding of the PF/VF drivers so I
may be missing something; but we are seeing the segfault on those lines in
v20.05 at least. I couldn't find a related patch/commit but wanted to check
if my reasoning was correct before adding this 1 line fix.


Thanks,
Stefan Baranoff