mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Karan Sanghavi <karansanghvi98@gmail.com>
To: Chun-Kuang Hu <chunkuang.hu@kernel.org>,
	 Philipp Zabel <p.zabel@pengutronix.de>,
	David Airlie <airlied@gmail.com>,
	 Simona Vetter <simona@ffwll.ch>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	 AngeloGioacchino Del Regno
	<angelogioacchino.delregno@collabora.com>,
	 Alexandre Mergnat <amergnat@baylibre.com>,
	 Sui Jingfeng <sui.jingfeng@linux.dev>,
	CK Hu <ck.hu@mediatek.com>
Cc: dri-devel@lists.freedesktop.org,
	linux-mediatek@lists.infradead.org,
	 linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	 Shuah Khan <skhan@linuxfoundation.org>,
	 Karan Sanghavi <karansanghvi98@gmail.com>
Subject: [PATCH] drm/mediatek: Initialize pointer before use to avoid undefiend behaviour
Date: Mon, 11 Nov 2024 18:14:43 +0000	[thread overview]
Message-ID: <20241111-uninitializedpointer1601557-v1-1-7d03668e8141@gmail.com> (raw)

Initialize the pointer with NULL as mtk_drm_of_get_ddp_ep_cid
function might return before assigning value to next pointer
but yet further dereference to next can lead to some undefined
behavior as it may point to some invalid location.

Fixes: 4c932840db1d ("drm/mediatek: Implement OF graphs support for display paths")
Signed-off-by: Karan Sanghavi <karansanghvi98@gmail.com>
---
Coverity Message:
CID 1601557: (#1 of 1): Uninitialized pointer read (UNINIT)
3. uninit_use: Using uninitialized value next.

Coverity Link:
https://scan7.scan.coverity.com/#/project-view/10043/11354?selectedIssue=1601557
---
 drivers/gpu/drm/mediatek/mtk_drm_drv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index 9a8ef8558da9..bc06c664e80f 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -900,7 +900,7 @@ static int mtk_drm_of_ddp_path_build_one(struct device *dev, enum mtk_crtc_path
 					 const unsigned int **out_path,
 					 unsigned int *out_path_len)
 {
-	struct device_node *next, *prev, *vdo = dev->parent->of_node;
+	struct device_node *next = NULL, *prev, *vdo = dev->parent->of_node;
 	unsigned int temp_path[DDP_COMPONENT_DRM_ID_MAX] = { 0 };
 	unsigned int *final_ddp_path;
 	unsigned short int idx = 0;

---
base-commit: 6d59cab07b8d74d0f0422b750038123334f6ecc2
change-id: 20241111-uninitializedpointer1601557-9803b725b6bd

Best regards,
-- 
Karan Sanghavi <karansanghvi98@gmail.com>


             reply	other threads:[~2024-11-11 18:14 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-11-11 18:14 Karan Sanghavi [this message]
2024-12-24  8:34 ` CK Hu (胡俊光)
2024-12-24 16:09 ` Markus Elfring
2024-12-27  9:51   ` Karan Sanghavi
2024-12-27 10:24     ` Markus Elfring

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20241111-uninitializedpointer1601557-v1-1-7d03668e8141@gmail.com \
    --to=karansanghvi98@gmail.com \
    --cc=airlied@gmail.com \
    --cc=amergnat@baylibre.com \
    --cc=angelogioacchino.delregno@collabora.com \
    --cc=chunkuang.hu@kernel.org \
    --cc=ck.hu@mediatek.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=matthias.bgg@gmail.com \
    --cc=p.zabel@pengutronix.de \
    --cc=simona@ffwll.ch \
    --cc=skhan@linuxfoundation.org \
    --cc=sui.jingfeng@linux.dev \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®