lkml.org 
[lkml]   [2021]   [Apr]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subject[BUG] ethernet:enic: A use after free bug in enic_hard_start_xmit
Hi, maintainers.
Our code analyzer reported a uaf bug, but it is a little
difficult for me to fix it directly.

File: drivers/net/ethernet/cisco/enic/enic_main.c
In enic_hard_start_xmit, it calls enic_queue_wq_skb(). Inside
enic_queue_wq_skb, if some error happens, the skb will be freed
by dev_kfree_skb(skb). But the freed skb is still used in
skb_tx_timestamp(skb).

```
enic_queue_wq_skb(enic, wq, skb);// skb could freed here

if (vnic_wq_desc_avail(wq) < MAX_SKB_FRAGS + ENIC_DESC_MAX_SPLITS)
netif_tx_stop_queue(txq);
skb_tx_timestamp(skb); // freed skb is used here.
```
Bug introduced by fb7516d42478e ("enic: add sw timestamp support").

Thanks for your time, looking forwarding to your reply.
Lv Yunlong <lyl2019@mail.ustc.edu.cn>

\
 
 \ /
  Last update: 2021-04-27 04:56    [W:0.055 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site