Re: [PATCH] drm/msm/dpu: reorder pointer operations after sanity checks to avoid NULL deref

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To: Qasim Ijaz <qasdev00@xxxxxxxxx>, dri-devel@xxxxxxxxxxxxxxxxxxxxx, freedreno@xxxxxxxxxxxxxxxxxxxxx, linux-arm-msm@xxxxxxxxxxxxxxx

Subject: Re: [PATCH] drm/msm/dpu: reorder pointer operations after sanity checks to avoid NULL deref

From: Markus Elfring <Markus.Elfring@xxxxxx>

Date: Sun, 9 Mar 2025 11:00:15 +0100

Cc: LKML <linux-kernel@xxxxxxxxxxxxxxx>, Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>, David Airlie <airlied@xxxxxxxxx>, Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>, Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>, Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>, Rob Clark <robdclark@xxxxxxxxx>, Sean Paul <sean@xxxxxxxxxx>, Simona Vetter <simona@xxxxxxxx>

In-reply-to: <20250308144839.33849-1-qasdev00@gmail.com>

References: <20250308144839.33849-1-qasdev00@gmail.com>

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User-agent: Mozilla Thunderbird

…
> Fix this by reordering the dereference after the sanity checks.

Another wording suggestion:
Thus move the assignment of the variable “dpu_enc” behind a null pointer check.


Would an other summary phrase be nicer?

Regards,
Markus