From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A967F1C03 for ; Mon, 20 Mar 2023 15:15:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2A052C433D2; Mon, 20 Mar 2023 15:15:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1679325317; bh=dTqqnBtIoFk9VceyZ0w0v7RtRo8JyQSF6PysbcSkc5s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yvGenS9oKjUDT+pcAT5vWyA84RIZoR4ixfk5tolwsklmyzXh/Z2VTmHdXcDR5sfmG iS1/Dn7yrv8sBCslsAVDkje4H+zJXYFAKYgAYvWQN3YG4fkreS8+e8eWxNLgDmSLZh saME0CoZiFmWuwyt5XlARBGNMj8XKGOfBst0W0VA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dmitry Osipenko , Rob Clark Subject: [PATCH 5.15 090/115] drm/shmem-helper: Remove another errant put in error path Date: Mon, 20 Mar 2023 15:55:02 +0100 Message-Id: <20230320145453.189399602@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230320145449.336983711@linuxfoundation.org> References: <20230320145449.336983711@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Dmitry Osipenko commit ee9adb7a45516cfa536ca92253d7ae59d56db9e4 upstream. drm_gem_shmem_mmap() doesn't own reference in error code path, resulting in the dma-buf shmem GEM object getting prematurely freed leading to a later use-after-free. Fixes: f49a51bfdc8e ("drm/shme-helpers: Fix dma_buf_mmap forwarding bug") Cc: stable@vger.kernel.org Signed-off-by: Dmitry Osipenko Reviewed-by: Rob Clark Link: https://patchwork.freedesktop.org/patch/msgid/20230108211311.3950107-1-dmitry.osipenko@collabora.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_gem_shmem_helper.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -591,11 +591,14 @@ int drm_gem_shmem_mmap(struct drm_gem_sh int ret; if (obj->import_attach) { - /* Drop the reference drm_gem_mmap_obj() acquired.*/ - drm_gem_object_put(obj); vma->vm_private_data = NULL; + ret = dma_buf_mmap(obj->dma_buf, vma, 0); + + /* Drop the reference drm_gem_mmap_obj() acquired.*/ + if (!ret) + drm_gem_object_put(obj); - return dma_buf_mmap(obj->dma_buf, vma, 0); + return ret; } ret = drm_gem_shmem_get_pages(shmem);