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From:   Haowen Bai <baihaowen@meizu.com>
To:     Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>
CC:     Haowen Bai <baihaowen@meizu.com>, <linux-arm-msm@vger.kernel.org>,
        <dri-devel@lists.freedesktop.org>,
        <freedreno@lists.freedesktop.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH] drm/msm/dpu: Fix pointer dereferenced before checking
Date:   Mon, 30 May 2022 10:19:55 +0800
Message-ID: <1653877196-23114-1-git-send-email-baihaowen@meizu.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

The phys_enc->wb_idx is dereferencing before null checking, so move
it after checking.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c
index 4829d1ce0cf8..59da348ff339 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c
@@ -574,11 +574,11 @@ static void dpu_encoder_phys_wb_disable(struct dpu_encoder_phys *phys_enc)
  */
 static void dpu_encoder_phys_wb_destroy(struct dpu_encoder_phys *phys_enc)
 {
-	DPU_DEBUG("[wb:%d]\n", phys_enc->wb_idx - WB_0);
-
 	if (!phys_enc)
 		return;
 
+	DPU_DEBUG("[wb:%d]\n", phys_enc->wb_idx - WB_0);
+
 	kfree(phys_enc);
 }
 
-- 
2.7.4