From nobody Mon Jun 8 04:25:38 2026 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) (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 30D5237BE74; Sun, 7 Jun 2026 09:03:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.81 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780823010; cv=none; b=Lvxm6ZRVkEgkySyib6596QWgv7Ie0s5zLH1H+/fLL3r4lu9RKx/GzjzA71h8EpFUz+EB622iEHQRerGwvQXStAwYh4jAYxeFjXx1lmtnSnECAkIySN+lMwjznMwBnyxl/R/c+x+scU5ozGQdyqgrm4X7EGtT2n3Ry8KohIIlgT4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780823010; c=relaxed/simple; bh=4SUUNkzDJdg4r/FrEuPSg45I4nO6KJLxlg215SpNcaE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Xd3C0bPLE+TB7DmLFbJL4xBzQpwdZfsIa5SnZofF1KO/rxfUrgEFUQjdmAEFBVyV343AneJNQu6DI+tmgR2i0BMtmQNrQ5m9mv/cc9JthFvc40jk+puqoPwKBy+9R2Jz90cIwq+LmZERaEcE/UTNSvqUEEY8rwsUFo3dTheNgBc= 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=159.226.251.81 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 dfae2b116770.home.arpa (unknown [36.110.52.2]) by APP-03 (Coremail) with SMTP id rQCowAAXKtHQMyVqoCbkEw--.5129S2; Sun, 07 Jun 2026 17:03:12 +0800 (CST) From: Wentao Liang To: airlied@redhat.com, kraxel@redhat.com, dmitry.osipenko@collabora.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, simona@ffwll.ch Cc: gurchetansingh@chromium.org, olvaffe@gmail.com, dri-devel@lists.freedesktop.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, Wentao Liang , stable@vger.kernel.org Subject: [PATCH] drm/virtio: fix dma_fence refcount leak on error in virtio_gpu_dma_fence_wait() Date: Sun, 7 Jun 2026 09:03:03 +0000 Message-Id: <20260607090303.92423-1-vulab@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: rQCowAAXKtHQMyVqoCbkEw--.5129S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Cr45GrWxXryxKryfKw47twb_yoW8GFWxpa 18G343CFnIya1Iqay7A3W09ryrC3ZxArWSgF4j9ayfCwn8XF15tr1DA3ySqryDAFZrt3yf Krn7Cr4YgFn5uaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9214x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwVC2z280aVCY1x0267AKxVWxJr 0_GcWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_JF0_Jw1lYx0Ex4A2jsIE14v26r4UJVWxJr1lOx8S6xCaFVCjc4AY6r 1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02 628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4 IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1r MI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJV WUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j 6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYx BIdaVFxhVjvjDU0xZFpf9x0JUJWrAUUUUU= X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiBwwLA2ok4-xRfwABs9 Content-Type: text/plain; charset="utf-8" dma_fence_unwrap_for_each() internally calls dma_fence_unwrap_first() which does cursor->chain =3D dma_fence_get(head), taking an extra reference. On normal loop completion, dma_fence_unwrap_next() releases this via dma_fence_chain_walk() -> dma_fence_put(). When virtio_gpu_do_fence_wait() fails and the function returns early from inside the loop, the cursor->chain reference is never released. This is the only caller in the entire kernel that does an early return inside dma_fence_unwrap_for_each. Add dma_fence_put(itr.chain) before the early return. Cc: stable@vger.kernel.org Fixes: eba57fb5498f ("drm/virtio: Wait for each dma-fence of in-fence array= individually") Signed-off-by: Wentao Liang --- drivers/gpu/drm/virtio/virtgpu_submit.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_submit.c b/drivers/gpu/drm/virt= io/virtgpu_submit.c index dae761fa5788..32cb1e4aa425 100644 --- a/drivers/gpu/drm/virtio/virtgpu_submit.c +++ b/drivers/gpu/drm/virtio/virtgpu_submit.c @@ -65,8 +65,10 @@ static int virtio_gpu_dma_fence_wait(struct virtio_gpu_s= ubmit *submit, =20 dma_fence_unwrap_for_each(f, &itr, fence) { err =3D virtio_gpu_do_fence_wait(submit, f); - if (err) + if (err) { + dma_fence_put(itr.chain); return err; + } } =20 return 0; --=20 2.34.1