From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kevin Cernekee , Rob Herring Subject: [PATCH 3.17 075/122] of: Fix crash if an earlycon driver is not found Date: Fri, 5 Dec 2014 14:44:09 -0800 Message-Id: <20141205223317.075077519@linuxfoundation.org> In-Reply-To: <20141205223305.514276242@linuxfoundation.org> References: <20141205223305.514276242@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kevin Cernekee commit ab74d00a39f70e1bc34a01322bb59f3750ca7a8c upstream. __earlycon_of_table_sentinel.compatible is a char[128], not a pointer, so it will never be NULL. Checking it against NULL causes the match loop to run past the end of the array, and eventually match a bogus entry, under the following conditions: - Kernel command line specifies "earlycon" with no parameters - DT has a stdout-path pointing to a UART node - The UART driver doesn't use OF_EARLYCON_DECLARE (or maybe the console driver is compiled out) Fix this by checking to see if match->compatible is a non-empty string. Signed-off-by: Kevin Cernekee Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman --- drivers/of/fdt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -773,7 +773,7 @@ int __init early_init_dt_scan_chosen_ser if (offset < 0) return -ENODEV; - while (match->compatible) { + while (match->compatible[0]) { unsigned long addr; if (fdt_node_check_compatible(fdt, offset, match->compatible)) { match++;