From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:49890 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755558AbbHNQq7 (ORCPT ); Fri, 14 Aug 2015 12:46:59 -0400 Subject: Patch "signal: fix information leak in copy_siginfo_to_user" has been added to the 3.10-stable tree To: amanieu@gmail.com, akpm@linux-foundation.org, gregkh@linuxfoundation.org, mingo@kernel.org, oleg@redhat.com, rmk@arm.linux.org.uk, torvalds@linux-foundation.org Cc: , From: Date: Fri, 14 Aug 2015 09:46:58 -0700 Message-ID: <14395708184369@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled signal: fix information leak in copy_siginfo_to_user to the 3.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: signal-fix-information-leak-in-copy_siginfo_to_user.patch and it can be found in the queue-3.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 26135022f85105ad725cda103fa069e29e83bd16 Mon Sep 17 00:00:00 2001 From: Amanieu d'Antras Date: Thu, 6 Aug 2015 15:46:29 -0700 Subject: signal: fix information leak in copy_siginfo_to_user From: Amanieu d'Antras commit 26135022f85105ad725cda103fa069e29e83bd16 upstream. This function may copy the si_addr_lsb, si_lower and si_upper fields to user mode when they haven't been initialized, which can leak kernel stack data to user mode. Just checking the value of si_code is insufficient because the same si_code value is shared between multiple signals. This is solved by checking the value of si_signo in addition to si_code. Signed-off-by: Amanieu d'Antras Cc: Oleg Nesterov Cc: Ingo Molnar Cc: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/signal32.c | 3 ++- kernel/signal.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) --- a/arch/arm64/kernel/signal32.c +++ b/arch/arm64/kernel/signal32.c @@ -193,7 +193,8 @@ int copy_siginfo_to_user32(compat_siginf * Other callers might not initialize the si_lsb field, * so check explicitely for the right codes here. */ - if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO) + if (from->si_signo == SIGBUS && + (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif break; --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2768,7 +2768,8 @@ int copy_siginfo_to_user(siginfo_t __use * Other callers might not initialize the si_lsb field, * so check explicitly for the right codes here. */ - if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO) + if (from->si_signo == SIGBUS && + (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif break; Patches currently in stable-queue which might be from amanieu@gmail.com are queue-3.10/signal-fix-information-leak-in-copy_siginfo_from_user32.patch queue-3.10/signal-fix-information-leak-in-copy_siginfo_to_user.patch queue-3.10/signalfd-fix-information-leak-in-signalfd_copyinfo.patch