From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:46502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730810AbeLKP53 (ORCPT ); Tue, 11 Dec 2018 10:57:29 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, William Cohen , Laura Abbott , Masami Hiramatsu , Kees Cook , Russell King Subject: [PATCH 4.19 088/118] ARM: 8806/1: kprobes: Fix false positive with FORTIFY_SOURCE Date: Tue, 11 Dec 2018 16:41:47 +0100 Message-Id: <20181211151647.822266181@linuxfoundation.org> In-Reply-To: <20181211151644.216668863@linuxfoundation.org> References: <20181211151644.216668863@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kees Cook commit e46daee53bb50bde38805f1823a182979724c229 upstream. The arm compiler internally interprets an inline assembly label as an unsigned long value, not a pointer. As a result, under CONFIG_FORTIFY_SOURCE, the address of a label has a size of 4 bytes, which was tripping the runtime checks. Instead, we can just cast the label (as done with the size calculations earlier). Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1639397 Reported-by: William Cohen Fixes: 6974f0c4555e ("include/linux/string.h: add the option of fortified string.h functions") Cc: stable@vger.kernel.org Acked-by: Laura Abbott Acked-by: Masami Hiramatsu Tested-by: William Cohen Signed-off-by: Kees Cook Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman --- arch/arm/probes/kprobes/opt-arm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/arm/probes/kprobes/opt-arm.c +++ b/arch/arm/probes/kprobes/opt-arm.c @@ -247,7 +247,7 @@ int arch_prepare_optimized_kprobe(struct } /* Copy arch-dep-instance from template. */ - memcpy(code, &optprobe_template_entry, + memcpy(code, (unsigned char *)optprobe_template_entry, TMPL_END_IDX * sizeof(kprobe_opcode_t)); /* Adjust buffer according to instruction. */