From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:37884 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751418AbdEPKwJ (ORCPT ); Tue, 16 May 2017 06:52:09 -0400 Subject: Patch "um: Fix PTRACE_POKEUSER on x86_64" has been added to the 3.18-stable tree To: richard@nod.at, cj3054@gmail.com, gregkh@linuxfoundation.org Cc: , From: Date: Tue, 16 May 2017 12:51:56 +0200 Message-ID: <149493191618338@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 um: Fix PTRACE_POKEUSER on x86_64 to the 3.18-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: um-fix-ptrace_pokeuser-on-x86_64.patch and it can be found in the queue-3.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 9abc74a22d85ab29cef9896a2582a530da7e79bf Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Sat, 1 Apr 2017 00:41:57 +0200 Subject: um: Fix PTRACE_POKEUSER on x86_64 From: Richard Weinberger commit 9abc74a22d85ab29cef9896a2582a530da7e79bf upstream. This is broken since ever but sadly nobody noticed. Recent versions of GDB set DR_CONTROL unconditionally and UML dies due to a heap corruption. It turns out that the PTRACE_POKEUSER was copy&pasted from i386 and assumes that addresses are 4 bytes long. Fix that by using 8 as address size in the calculation. Reported-by: jie cao Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman --- arch/x86/um/ptrace_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/um/ptrace_64.c +++ b/arch/x86/um/ptrace_64.c @@ -120,7 +120,7 @@ int poke_user(struct task_struct *child, else if ((addr >= offsetof(struct user, u_debugreg[0])) && (addr <= offsetof(struct user, u_debugreg[7]))) { addr -= offsetof(struct user, u_debugreg[0]); - addr = addr >> 2; + addr = addr >> 3; if ((addr == 4) || (addr == 5)) return -EIO; child->thread.arch.debugregs[addr] = data; Patches currently in stable-queue which might be from richard@nod.at are queue-3.18/um-fix-ptrace_pokeuser-on-x86_64.patch