From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:45592 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932777AbeCSJOv (ORCPT ); Mon, 19 Mar 2018 05:14:51 -0400 Subject: Patch "kprobes/x86: Set kprobes pages read-only" has been added to the 3.18-stable tree To: mhiramat@kernel.org, alexander.levin@microsoft.com, ananth@linux.vnet.ibm.com, anil.s.keshavamurthy@intel.com, aryabinin@virtuozzo.com, bp@alien8.de, brgerst@gmail.com, davem@davemloft.net, dvlasenk@redhat.com, gregkh@linuxfoundation.org, hpa@zytor.com, jpoimboe@redhat.com, mingo@kernel.org, peterz@infradead.org, tglx@linutronix.de, torvalds@linux-foundation.org, xiaolong.ye@intel.com Cc: , From: Date: Mon, 19 Mar 2018 10:13:06 +0100 Message-ID: <1521450786183134@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 kprobes/x86: Set kprobes pages read-only 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: kprobes-x86-set-kprobes-pages-read-only.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 foo@baz Mon Mar 19 10:11:52 CET 2018 From: Masami Hiramatsu Date: Wed, 29 Mar 2017 14:02:46 +0900 Subject: kprobes/x86: Set kprobes pages read-only From: Masami Hiramatsu [ Upstream commit d0381c81c2f782fa2131178d11e0cfb23d50d631 ] Set the pages which is used for kprobes' singlestep buffer and optprobe's trampoline instruction buffer to readonly. This can prevent unexpected (or unintended) instruction modification. This also passes rodata_test as below. Without this patch, rodata_test shows a warning: WARNING: CPU: 0 PID: 1 at arch/x86/mm/dump_pagetables.c:235 note_page+0x7a9/0xa20 x86/mm: Found insecure W+X mapping at address ffffffffa0000000/0xffffffffa0000000 With this fix, no W+X pages are found: x86/mm: Checked W+X mappings: passed, no W+X pages found. rodata_test: all tests were successful Reported-by: Andrey Ryabinin Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Anil S Keshavamurthy Cc: Borislav Petkov Cc: Brian Gerst Cc: David S . Miller Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ye Xiaolong Link: http://lkml.kernel.org/r/149076375592.22469.14174394514338612247.stgit@devbox Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/kprobes/core.c | 4 ++++ arch/x86/kernel/kprobes/opt.c | 3 +++ 2 files changed, 7 insertions(+) --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -378,6 +378,8 @@ static int arch_copy_kprobe(struct kprob { int ret; + set_memory_rw((unsigned long)p->ainsn.insn & PAGE_MASK, 1); + /* Copy an instruction with recovering if other optprobe modifies it.*/ ret = __copy_instruction(p->ainsn.insn, p->addr); if (!ret) @@ -392,6 +394,8 @@ static int arch_copy_kprobe(struct kprob else p->ainsn.boostable = -1; + set_memory_ro((unsigned long)p->ainsn.insn & PAGE_MASK, 1); + /* Check whether the instruction modifies Interrupt Flag or not */ p->ainsn.if_modifier = is_IF_modifier(p->ainsn.insn); --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -344,6 +344,7 @@ int arch_prepare_optimized_kprobe(struct } buf = (u8 *)op->optinsn.insn; + set_memory_rw((unsigned long)buf & PAGE_MASK, 1); /* Copy instructions into the out-of-line buffer */ ret = copy_optimized_instructions(buf + TMPL_END_IDX, op->kp.addr); @@ -366,6 +367,8 @@ int arch_prepare_optimized_kprobe(struct synthesize_reljump(buf + TMPL_END_IDX + op->optinsn.size, (u8 *)op->kp.addr + op->optinsn.size); + set_memory_ro((unsigned long)buf & PAGE_MASK, 1); + flush_icache_range((unsigned long) buf, (unsigned long) buf + TMPL_END_IDX + op->optinsn.size + RELATIVEJUMP_SIZE); Patches currently in stable-queue which might be from mhiramat@kernel.org are queue-3.18/perf-session-don-t-rely-on-evlist-in-pipe-mode.patch queue-3.18/kprobes-x86-set-kprobes-pages-read-only.patch queue-3.18/kprobes-x86-fix-kprobe-booster-not-to-boost-far-call-instructions.patch queue-3.18/perf-inject-copy-events-when-reordering-events-in-pipe-mode.patch