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From:   YE Chengfeng <cyeaa@connect.ust.hk>
To:     "mturquette@baylibre.com" <mturquette@baylibre.com>,
        "sboyd@kernel.org" <sboyd@kernel.org>,
        "mripard@kernel.org" <mripard@kernel.org>,
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CC:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: drivers/clk/sunxi-ng: suspected missing null check for callsite of
 clk_hw_get_parent 
Thread-Topic: drivers/clk/sunxi-ng: suspected missing null check for callsite
 of clk_hw_get_parent 
Thread-Index: AdfKNUoa0glysWrhRPmS8LHgDDJ0YA==
Date:   Tue, 26 Oct 2021 06:47:15 +0000
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Hi,

https://github.com/torvalds/linux/blob/5bfc75d92efd494db37f5c4c173d3639d477=
2966/drivers/clk/sunxi-ng/ccu_gate.c#L101
https://github.com/torvalds/linux/blob/master/drivers/clk/sunxi-ng/ccu_mux.=
c#L93

Our experimental static analysis tool detects a null-ptr-reference problem.=
 It could be false positive, we report this to you just in case.

In these two call sites of clk_hw_get_parent, the return pointer is not nul=
l-check. We are not familiar with the code, and don't know whether it would=
 be a potential null pointer dereference problem. Would you like to spare s=
ome time to have a look at it?

Thanks so much,
Chengfeng