linux-kernel - [PATCH v3] media: platform: mtk-mdp3: Add missing check and free for ida

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Thu,  9 Feb 2023 17:25:02 +0800
From:   Jiasheng Jiang <jiasheng@...as.ac.cn>
To:     mchehab@...nel.org, matthias.bgg@...il.com,
        angelogioacchino.delregno@...labora.com, moudy.ho@...iatek.com,
        daoyuan.huang@...iatek.com, hverkuil-cisco@...all.nl
Cc:     linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org,
        Jiasheng Jiang <jiasheng@...as.ac.cn>
Subject: [PATCH v3] media: platform: mtk-mdp3: Add missing check and free for ida_alloc

Add the check for the return value of the ida_alloc in order to avoid
NULL pointer dereference.
Moreover, free allocated "ctx->id" if mdp_m2m_open fails later in order
to avoid memory leak.

Fixes: 61890ccaefaf ("media: platform: mtk-mdp3: add MediaTek MDP3 driver")
Signed-off-by: Jiasheng Jiang <jiasheng@...as.ac.cn>
---
Changelog:

v2 -> v3:

1. Fix the goto label.

v1 -> v2:

1. Fix the check for the ida_alloc.
---
 drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c
index 5f74ea3b7a52..a2d204e90aa4 100644
--- a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c
+++ b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-m2m.c
@@ -567,6 +567,11 @@ static int mdp_m2m_open(struct file *file)
 	}
 
 	ctx->id = ida_alloc(&mdp->mdp_ida, GFP_KERNEL);
+	if (ctx->id < 0) {
+		ret = ctx->id;
+		goto err_unlock_mutex;
+	}
+
 	ctx->mdp_dev = mdp;
 
 	v4l2_fh_init(&ctx->fh, vdev);
@@ -617,6 +622,8 @@ static int mdp_m2m_open(struct file *file)
 	v4l2_fh_del(&ctx->fh);
 err_exit_fh:
 	v4l2_fh_exit(&ctx->fh);
+	ida_free(&mdp->mdp_ida, ctx->id);
+err_unlock_mutex:
 	mutex_unlock(&mdp->m2m_lock);
 err_free_ctx:
 	kfree(ctx);
-- 
2.25.1