From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14AF7C43387 for ; Wed, 16 Jan 2019 17:03:08 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 884BA20651 for ; Wed, 16 Jan 2019 17:03:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="unknown key hash" (0-bit key) header.d=c-s.fr header.i=@c-s.fr header.b="Khwl8Sdf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 884BA20651 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-s.fr Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43ftnP3d4TzDqlr for ; Thu, 17 Jan 2019 04:03:05 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=c-s.fr (client-ip=93.17.236.30; helo=pegase1.c-s.fr; envelope-from=christophe.leroy@c-s.fr; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=c-s.fr Authentication-Results: lists.ozlabs.org; dkim=fail reason="unknown key hash" (0-bit key; unprotected) header.d=c-s.fr header.i=@c-s.fr header.b="Khwl8Sdf"; dkim-atps=neutral Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43ftjK1dX6zDqkq for ; Thu, 17 Jan 2019 03:59:33 +1100 (AEDT) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 43ftjD3zfTz9vBmT; Wed, 16 Jan 2019 17:59:28 +0100 (CET) Authentication-Results: localhost; dkim=pass reason="1024-bit key; insecure key" header.d=c-s.fr header.i=@c-s.fr header.b=Khwl8Sdf; dkim-adsp=pass; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id wQTomXkCom_3; Wed, 16 Jan 2019 17:59:28 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 43ftjD2XzQz9vBmJ; Wed, 16 Jan 2019 17:59:28 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c-s.fr; s=mail; t=1547657968; bh=VS0H/GV7FY7nPJrZuJkENuwqd89d98HCiR9a0gQHbK0=; h=In-Reply-To:References:From:Subject:To:Cc:Date:From; b=Khwl8SdfOqxJHr3TpI4Ab+XN4eSlHofcgIrMBmybK/gWc5pwMocRAVp83IpnJPZq3 znvEFmndmjTzi87TTQhg7VgK93YoP8wDLDM4QWLw/eSeC7Gu/IgnaHDlp7sXyrWc2G ttiL9QqBkoagXDpe0x05dR233sXigz7frh3vgV+I= Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id CD6738B84F; Wed, 16 Jan 2019 17:59:29 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id vMtuhXty79AC; Wed, 16 Jan 2019 17:59:29 +0100 (CET) Received: from po16846vm.idsi0.si.c-s.fr (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 8300D8B84C; Wed, 16 Jan 2019 17:59:29 +0100 (CET) Received: by po16846vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 4C18A7187C; Wed, 16 Jan 2019 16:59:29 +0000 (UTC) Message-Id: In-Reply-To: <39fb6c5a191025378676492e140dc012915ecaeb.1547652372.git.christophe.leroy@c-s.fr> References: <39fb6c5a191025378676492e140dc012915ecaeb.1547652372.git.christophe.leroy@c-s.fr> From: Christophe Leroy Subject: [PATCH v3 2/2] powerpc: use probe_user_read() To: Kees Cook , Andrew Morton , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Mike Rapoport Date: Wed, 16 Jan 2019 16:59:29 +0000 (UTC) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Instead of opencoding, use probe_user_read() to failessly read a user location. Signed-off-by: Christophe Leroy --- v3: No change v2: Using probe_user_read() instead of probe_user_address() arch/powerpc/kernel/process.c | 12 +----------- arch/powerpc/mm/fault.c | 6 +----- arch/powerpc/perf/callchain.c | 20 +++----------------- arch/powerpc/perf/core-book3s.c | 8 +------- arch/powerpc/sysdev/fsl_pci.c | 10 ++++------ 5 files changed, 10 insertions(+), 46 deletions(-) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index ce393df243aa..6a4b59d574c2 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1298,16 +1298,6 @@ void show_user_instructions(struct pt_regs *regs) pc = regs->nip - (NR_INSN_TO_PRINT * 3 / 4 * sizeof(int)); - /* - * Make sure the NIP points at userspace, not kernel text/data or - * elsewhere. - */ - if (!__access_ok(pc, NR_INSN_TO_PRINT * sizeof(int), USER_DS)) { - pr_info("%s[%d]: Bad NIP, not dumping instructions.\n", - current->comm, current->pid); - return; - } - seq_buf_init(&s, buf, sizeof(buf)); while (n) { @@ -1318,7 +1308,7 @@ void show_user_instructions(struct pt_regs *regs) for (i = 0; i < 8 && n; i++, n--, pc += sizeof(int)) { int instr; - if (probe_kernel_address((const void *)pc, instr)) { + if (probe_user_read(&instr, (void __user *)pc, sizeof(instr))) { seq_buf_printf(&s, "XXXXXXXX "); continue; } diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 887f11bcf330..ec74305fa330 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -276,12 +276,8 @@ static bool bad_stack_expansion(struct pt_regs *regs, unsigned long address, if ((flags & FAULT_FLAG_WRITE) && (flags & FAULT_FLAG_USER) && access_ok(nip, sizeof(*nip))) { unsigned int inst; - int res; - pagefault_disable(); - res = __get_user_inatomic(inst, nip); - pagefault_enable(); - if (!res) + if (!probe_user_read(&inst, nip, sizeof(inst))) return !store_updates_sp(inst); *must_retry = true; } diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c index 0af051a1974e..0680efb2237b 100644 --- a/arch/powerpc/perf/callchain.c +++ b/arch/powerpc/perf/callchain.c @@ -159,12 +159,8 @@ static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret) ((unsigned long)ptr & 7)) return -EFAULT; - pagefault_disable(); - if (!__get_user_inatomic(*ret, ptr)) { - pagefault_enable(); + if (!probe_user_read(ret, ptr, sizeof(*ret))) return 0; - } - pagefault_enable(); return read_user_stack_slow(ptr, ret, 8); } @@ -175,12 +171,8 @@ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) ((unsigned long)ptr & 3)) return -EFAULT; - pagefault_disable(); - if (!__get_user_inatomic(*ret, ptr)) { - pagefault_enable(); + if (!probe_user_read(ret, ptr, sizeof(*ret))) return 0; - } - pagefault_enable(); return read_user_stack_slow(ptr, ret, 4); } @@ -307,17 +299,11 @@ static inline int current_is_64bit(void) */ static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret) { - int rc; - if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) || ((unsigned long)ptr & 3)) return -EFAULT; - pagefault_disable(); - rc = __get_user_inatomic(*ret, ptr); - pagefault_enable(); - - return rc; + return probe_user_read(ret, ptr, sizeof(*ret)); } static inline void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry, diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index b0723002a396..4b64ddf0db68 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -416,7 +416,6 @@ static void power_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) static __u64 power_pmu_bhrb_to(u64 addr) { unsigned int instr; - int ret; __u64 target; if (is_kernel_addr(addr)) { @@ -427,13 +426,8 @@ static __u64 power_pmu_bhrb_to(u64 addr) } /* Userspace: need copy instruction here then translate it */ - pagefault_disable(); - ret = __get_user_inatomic(instr, (unsigned int __user *)addr); - if (ret) { - pagefault_enable(); + if (probe_user_read(&instr, (unsigned int __user *)addr, sizeof(instr))) return 0; - } - pagefault_enable(); target = branch_target(&instr); if ((!target) || (instr & BRANCH_ABSOLUTE)) diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c index 918be816b097..c8a1b26489f5 100644 --- a/arch/powerpc/sysdev/fsl_pci.c +++ b/arch/powerpc/sysdev/fsl_pci.c @@ -1068,13 +1068,11 @@ int fsl_pci_mcheck_exception(struct pt_regs *regs) addr += mfspr(SPRN_MCAR); if (is_in_pci_mem_space(addr)) { - if (user_mode(regs)) { - pagefault_disable(); - ret = get_user(inst, (__u32 __user *)regs->nip); - pagefault_enable(); - } else { + if (user_mode(regs)) + ret = probe_user_read(&inst, (void __user *)regs->nip, + sizeof(inst)); + else ret = probe_kernel_address((void *)regs->nip, inst); - } if (!ret && mcheck_handle_load(regs, inst)) { regs->nip += 4; -- 2.13.3