From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8908FA3728 for ; Wed, 16 Oct 2019 22:13:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C05F1207FF for ; Wed, 16 Oct 2019 22:13:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571264004; bh=j6J6/XrfGH0dGCQ64DCTclHY+iBTFT8Fgdv2TEDikSw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wu8lO9YuaSZwRpFyUzb7BH4nIA6PaNC/iWdJpMB7OFtsY8LVZRoRA4PSP0ClgRRQf CRmq2n8ogNcf3xIlXP+6DoX/umum8KfPqaleO4mLslvr2WbCqDjbGcD9RU7rpznZbM 90vBWF08GwgaJCK4SDhdAtqZglntPwMceXtvB5lM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439315AbfJPWNX (ORCPT ); Wed, 16 Oct 2019 18:13:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:47004 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2437843AbfJPVzy (ORCPT ); Wed, 16 Oct 2019 17:55:54 -0400 Received: from localhost (unknown [192.55.54.58]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AD5C4218DE; Wed, 16 Oct 2019 21:55:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571262953; bh=j6J6/XrfGH0dGCQ64DCTclHY+iBTFT8Fgdv2TEDikSw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sPsbSneWmjkLIL6ELXtQuK46gKUxmF2Z9PlO0E2VAhhxLVsB8U9UHEpsp/hDFJvtf Lj4XQ/DZcKwxPAX58Tb77JAWQl8g4ZmKV4TYmM2/WuwEOJWVfOb3/iL4PSbnpf11sF mgBe5rmVx/5eDZYFF9bl/J3yuCHdarwRa7SPnjs0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Randy Dunlap , Peter Korsgaard Subject: [PATCH 4.14 23/65] serial: uartlite: fix exit path null pointer Date: Wed, 16 Oct 2019 14:50:37 -0700 Message-Id: <20191016214819.179163209@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016214756.457746573@linuxfoundation.org> References: <20191016214756.457746573@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Randy Dunlap commit a553add0846f355a28ed4e81134012e4a1e280c2 upstream. Call uart_unregister_driver() conditionally instead of unconditionally, only if it has been previously registered. This uses driver.state, just as the sh-sci.c driver does. Fixes this null pointer dereference in tty_unregister_driver(), since the 'driver' argument is null: general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI RIP: 0010:tty_unregister_driver+0x25/0x1d0 Fixes: 238b8721a554 ("[PATCH] serial uartlite driver") Signed-off-by: Randy Dunlap Cc: stable Cc: Peter Korsgaard Link: https://lore.kernel.org/r/9c8e6581-6fcc-a595-0897-4d90f5d710df@infradead.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/uartlite.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/tty/serial/uartlite.c +++ b/drivers/tty/serial/uartlite.c @@ -746,7 +746,8 @@ err_uart: static void __exit ulite_exit(void) { platform_driver_unregister(&ulite_platform_driver); - uart_unregister_driver(&ulite_uart_driver); + if (ulite_uart_driver.state) + uart_unregister_driver(&ulite_uart_driver); } module_init(ulite_init);