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 31D39267F68; Tue, 8 Apr 2025 11:51:44 +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=1744113105; cv=none; b=QPIjz9R1ogHxc3QYG+XyOeWMAttu9FqPsZBgwjGCNrLoyizqTNlHa7GlCCX7i47WBeZaBmg7cp7Qgtdn8i67c/mIjTkO9h0IRXxDu/enSl3qhxwOnn+IOp9wbTh2GXlK/ronhDXoR8llManWENWDvygmhGjxjN/fO7cUvz0fdb8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744113105; c=relaxed/simple; bh=psMwmmG7prNurx5+P2JzdIpchLZCqg3pYS0otxdMnLM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ZI853YgzhN0cYj14UIgUfLlSJwYGQnG99l0QIjarriLZ9uQRaSTLXkHz88gFF3XWlxaVij3css1VDmqptnC4Hh0QlRfIowczpSjlw87EH+pPWvLLbhu+f/Nzo0bBUmSdNc5EcX+BUANvxQOuNqs47hVDzccN5a65Xog04CbmIVQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zpKyYTLV; 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="zpKyYTLV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60931C4CEE5; Tue, 8 Apr 2025 11:51:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744113104; bh=psMwmmG7prNurx5+P2JzdIpchLZCqg3pYS0otxdMnLM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zpKyYTLV9bVI93XsuFqS2gVIXIIgXXp0+i/B9jVssrFqmHOjMbLUl00VF5yaGrF1x Afs7fZOZj2gPfi5dwXVofgdJvocuQm4gFmGg4D2FJVYBKr+xoHMOqbAQcfH1p95dEk Q4BMNlyEnKsYtoRzvP4Btw/t4nxPMMtjqXhblQbA= 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 6.6 036/268] drm/vkms: Fix use after free and double free on init error Date: Tue, 8 Apr 2025 12:47:27 +0200 Message-ID: <20250408104829.473896269@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104828.499967190@linuxfoundation.org> References: <20250408104828.499967190@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 6.6-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 dd0af086e7fa9..25db36ec06d49 100644 --- a/drivers/gpu/drm/vkms/vkms_drv.c +++ b/drivers/gpu/drm/vkms/vkms_drv.c @@ -243,17 +243,19 @@ 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) @@ -277,9 +279,10 @@ 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