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From: Li Tuo <>
Subject: [BUG] mwifiex: possible null-pointer dereference in mwifiex_dnld_cmd_to_fw()
Date: Sat, 31 Jul 2021 11:45:46 +0800	[thread overview]
Message-ID: <> (raw)


Our static analysis tool finds a possible null-pointer dereference in 
the mwifiex driver in Linux 5.14.0-rc3:

The variable cmd_node->cmd_skb->data is assigned to the variable 
host_cmd, and host_cmd is checked in:
190:    if (host_cmd == NULL || host_cmd->size == 0)

This indicates that host_cmd can be NULL.
If so, the function mwifiex_recycle_cmd_node() will be called with the 
argument cmd_node:
196:    mwifiex_recycle_cmd_node(adapter, cmd_node);

In this called function, the variable cmd_node->cmd_skb->data is 
assigned to the variable host_cmd, too.
Thus the variable host_cmd in the function mwifiex_recycle_cmd_node() 
can be also NULL.
However, it is dereferenced when calling le16_to_cpu():
144:    le16_to_cpu(host_cmd->command)

I am not quite sure whether this possible null-pointer dereference is 
real and how to fix it if it is real.
Any feedback would be appreciated, thanks!

Reported-by: TOTE Robot <>

Best wishes,
Tuo Li

             reply	other threads:[~2021-07-31  3:45 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-31  3:45 Li Tuo [this message]
2021-07-31  4:13 Li Tuo
2021-08-02 20:44 ` Brian Norris
2021-08-03  2:34   ` Li Tuo

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