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 9AFA6268690; Tue, 8 Apr 2025 11:16:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744111015; cv=none; b=kbqoHqwBmecCFDKS/JG6EGoxGeAQHJIeRHTEaGkYTDWsI3jd3Ma7fAP+qc5d3Ouby/SxchFLvBik+69fmCzVXT+M0NRHS1pQdkqLBuzUG8xXmJ8SrQwLIVFByzCMvT5EHKwc8e+2fyy7b/AjDUibrqp+QTXC2Q/sZq297E01/Io= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744111015; c=relaxed/simple; bh=CLxMgQxkFOW7FLmZfjdqEz1Kzjd4mLLPKo0EZfSTZe4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=JO95+nyuV+EbW1Vx8ahv1nqiJNMGf9VBJmQANViAKSsJWgV4nFnqOT+WIzM+teutlszCUhicTNU/sAXbnV/1MnKNYDPeFu8d3GeL6Pmf/givwMW0w4w3LxYsKmFEsO1dwkgFmCMBtQdNX0KgwRML6mYna1thxhRHjRZcC9LyLcM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JZSCuQNP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="JZSCuQNP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 243BDC4CEE5; Tue, 8 Apr 2025 11:16:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744111015; bh=CLxMgQxkFOW7FLmZfjdqEz1Kzjd4mLLPKo0EZfSTZe4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JZSCuQNPW77ZLzaI99gEPGNJCZrqaoczbpNgWAAUlFedXuzbmATwnxpUJZKxcvplP iFigdNO9BlqNWSE6fTviJF1DppQjd4c7hO72VdQDZGuikYaZjO9NHzBecgjOY5GIMz GMhFFhkDsDLyLwGoeprdvd4/AzECIEYjXGQayq4E= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Louis Chauvet , =?UTF-8?q?Jos=C3=A9=20Exp=C3=B3sito?= , Thomas Zimmermann , Sasha Levin Subject: [PATCH 6.14 278/731] drm/vkms: Fix use after free and double free on init error Date: Tue, 8 Apr 2025 12:42:55 +0200 Message-ID: <20250408104920.745243041@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104914.247897328@linuxfoundation.org> References: <20250408104914.247897328@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: José Expósito [ Upstream commit ed15511a773df86205bda66c37193569575ae828 ] If the driver initialization fails, the vkms_exit() function might access an uninitialized or freed default_config pointer and it might double free it. Fix both possible errors by initializing default_config only when the driver initialization succeeded. Reported-by: Louis Chauvet Closes: https://lore.kernel.org/all/Z5uDHcCmAwiTsGte@louis-chauvet-laptop/ Fixes: 2df7af93fdad ("drm/vkms: Add vkms_config type") Signed-off-by: José Expósito Reviewed-by: Thomas Zimmermann Reviewed-by: Louis Chauvet Link: https://patchwork.freedesktop.org/patch/msgid/20250212084912.3196-1-jose.exposito89@gmail.com Signed-off-by: Louis Chauvet Signed-off-by: Sasha Levin --- drivers/gpu/drm/vkms/vkms_drv.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c index e0409aba93496..7fefef690ab6b 100644 --- a/drivers/gpu/drm/vkms/vkms_drv.c +++ b/drivers/gpu/drm/vkms/vkms_drv.c @@ -244,17 +244,19 @@ static int __init vkms_init(void) if (!config) return -ENOMEM; - default_config = config; - config->cursor = enable_cursor; config->writeback = enable_writeback; config->overlay = enable_overlay; ret = vkms_create(config); - if (ret) + if (ret) { kfree(config); + return ret; + } - return ret; + default_config = config; + + return 0; } static void vkms_destroy(struct vkms_config *config) @@ -278,9 +280,10 @@ static void vkms_destroy(struct vkms_config *config) static void __exit vkms_exit(void) { - if (default_config->dev) - vkms_destroy(default_config); + if (!default_config) + return; + vkms_destroy(default_config); kfree(default_config); } -- 2.39.5