From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932636AbcC2URI (ORCPT ); Tue, 29 Mar 2016 16:17:08 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:45133 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758004AbcC2UE4 (ORCPT ); Tue, 29 Mar 2016 16:04:56 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Maciej W. Rozycki" , "Ralf Baechle" Date: Tue, 29 Mar 2016 20:18:22 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 56/62] MIPS: traps: Fix SIGFPE information leak from `do_ov' and `do_trap_or_bp' In-Reply-To: X-SA-Exim-Connect-IP: 213.146.164.225 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.79-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "Maciej W. Rozycki" commit e723e3f7f9591b79e8c56b3d7c5a204a9c571b55 upstream. Avoid sending a partially initialised `siginfo_t' structure along SIGFPE signals issued from `do_ov' and `do_trap_or_bp', leading to information leaking from the kernel stack. Signed-off-by: Maciej W. Rozycki Signed-off-by: Ralf Baechle [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- arch/mips/kernel/traps.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -656,14 +656,14 @@ static int simulate_sync(struct pt_regs asmlinkage void do_ov(struct pt_regs *regs) { - siginfo_t info; + siginfo_t info = { + .si_signo = SIGFPE, + .si_code = FPE_INTOVF, + .si_addr = (void __user *)regs->cp0_epc, + }; die_if_kernel("Integer overflow", regs); - info.si_code = FPE_INTOVF; - info.si_signo = SIGFPE; - info.si_errno = 0; - info.si_addr = (void __user *) regs->cp0_epc; force_sig_info(SIGFPE, &info, current); } @@ -758,7 +758,7 @@ asmlinkage void do_fpe(struct pt_regs *r static void do_trap_or_bp(struct pt_regs *regs, unsigned int code, const char *str) { - siginfo_t info; + siginfo_t info = { 0 }; char b[40]; #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP @@ -785,7 +785,6 @@ static void do_trap_or_bp(struct pt_regs else info.si_code = FPE_INTOVF; info.si_signo = SIGFPE; - info.si_errno = 0; info.si_addr = (void __user *) regs->cp0_epc; force_sig_info(SIGFPE, &info, current); break;