From nobody Wed Oct 1 21:23:23 2025 Received: from cstnet.cn (smtp84.cstnet.cn [159.226.251.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 434E9276057; Sat, 27 Sep 2025 09:48:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758966495; cv=none; b=bWVbzxNEi9rXNgo9DeIH7oxL92OTKy7k1z66xGembpZVJWVMKU9YQr3H+Qcw8OAOOvBOdaDJPDGJrQiKhcQLlQbwhm/2EquhaOrdF3R591oHT1H980LT1vUCSKUIYU4zDKSGTzg0uZFDYRh0ExP+kHzD4OJs9rerb4e5pPqDGYA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758966495; c=relaxed/simple; bh=zSpjC6m3pglcmLbIGjS2FcUdLFf8FTEZflp0fi6fCj0=; h=From:To:Cc:Subject:Date:Message-Id; b=FjQs2GL4rEZXxzD3JdR0sf6CbzO0NSRV7QB4syVSvQmwCkdud92Ka27AzpSjOhi1t0U1MXn6tmXMFFasds0Ouh/AS8uuzc4CpLSm6sj0ZFJixvoG31P73ApzleY71JB19iuUqSL9FNZ2m/H/8J/REye5Hp0uknZOk/+SLvdgr78= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [202.112.113.212]) by APP-05 (Coremail) with SMTP id zQCowADXeBLAstdoa+RcBw--.33407S2; Sat, 27 Sep 2025 17:47:57 +0800 (CST) From: Ma Ke To: thierry.reding@gmail.com, mperttunen@nvidia.com, airlied@gmail.com, simona@ffwll.ch, jonathanh@nvidia.com Cc: dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Ma Ke , stable@vger.kernel.org Subject: [PATCH] drm/tegra: dc: fix reference leak in tegra_dc_couple() Date: Sat, 27 Sep 2025 17:47:41 +0800 Message-Id: <20250927094741.9257-1-make24@iscas.ac.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: zQCowADXeBLAstdoa+RcBw--.33407S2 X-Coremail-Antispam: 1UD129KBjvdXoW7Xw15uFW5Zr1rAFy5KFW3Jrb_yoWfuFg_GF yUZryxW3yaqFsY9FnFvr13Zry2yFyq9FW0gr42k393Gry3XFyqg34jgFZ09ryUWa1UWFn8 AayrXr40vF12kjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbDxFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_ Cr1l84ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26F4UJV W0owAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr 1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IE rcIFxwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCY02Avz4vE14 v_GFWl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AK xVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrx kI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v2 6r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8Jw CI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUeF4EDUUU U X-CM-SenderInfo: ppdnvj2u6l2u1dvotugofq/ Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" driver_find_device() calls get_device() to increment the reference count once a matching device is found, but there is no put_device() to balance the reference count. To avoid reference count leakage, add put_device() to decrease the reference count. Found by code review. Cc: stable@vger.kernel.org Fixes: a31500fe7055 ("drm/tegra: dc: Restore coupling of display controller= s") Signed-off-by: Ma Ke --- drivers/gpu/drm/tegra/dc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c index 59d5c1ba145a..6c84bd69b11f 100644 --- a/drivers/gpu/drm/tegra/dc.c +++ b/drivers/gpu/drm/tegra/dc.c @@ -3148,6 +3148,7 @@ static int tegra_dc_couple(struct tegra_dc *dc) dc->client.parent =3D &parent->client; =20 dev_dbg(dc->dev, "coupled to %s\n", dev_name(companion)); + put_device(companion); } =20 return 0; --=20 2.17.1