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From:   YE Chengfeng <cyeaa@connect.ust.hk>
To:     "Eugeniy.Paltsev@synopsys.com" <Eugeniy.Paltsev@synopsys.com>,
        "vkoul@kernel.org" <vkoul@kernel.org>
CC:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: drivers/dma: suspected missing null-check issue in
 dw-axi-dmac/dw-axi-dmac-platform.c
Thread-Topic: drivers/dma: suspected missing null-check issue in
 dw-axi-dmac/dw-axi-dmac-platform.c
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Date:   Wed, 27 Oct 2021 11:55:44 +0000
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Hi,

https://github.com/torvalds/linux/blob/9840cfcb97fc8b6aa7b36cec3cc3fd763f14=
052e/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c#L982

We notice that null-check for the return pointer of vchan_next_desc exsits =
at #line 395, but is missing at #line 982 and #line 1018. Could it be a pot=
ential null-pointer-dereference pointer?

This is detected by our experimental static analysis tool, it could be fals=
e positive, we manually check and report those we think may be true issues.=
 Would you like to have a look at them?

Thanks so much,
Chengfeng