From patchwork Wed Dec 5 01:34:06 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nadav Amit X-Patchwork-Id: 10713325 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 19FD818A7 for ; Wed, 5 Dec 2018 08:52:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 092E82CCC3 for ; Wed, 5 Dec 2018 08:52:32 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F17DE2CCD0; Wed, 5 Dec 2018 08:52:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.4 required=2.0 tests=BAYES_00,DATE_IN_PAST_06_12, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5FFF52CCC3 for ; Wed, 5 Dec 2018 08:52:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726937AbeLEIwZ (ORCPT ); Wed, 5 Dec 2018 03:52:25 -0500 Received: from ex13-edg-ou-002.vmware.com ([208.91.0.190]:46460 "EHLO EX13-EDG-OU-002.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727458AbeLEIwN (ORCPT ); Wed, 5 Dec 2018 03:52:13 -0500 Received: from sc9-mailhost3.vmware.com (10.113.161.73) by EX13-EDG-OU-002.vmware.com (10.113.208.156) with Microsoft SMTP Server id 15.0.1156.6; Wed, 5 Dec 2018 00:52:03 -0800 Received: from sc2-haas01-esx0118.eng.vmware.com (sc2-haas01-esx0118.eng.vmware.com [10.172.44.118]) by sc9-mailhost3.vmware.com (Postfix) with ESMTP id 37C1841390; Wed, 5 Dec 2018 00:52:05 -0800 (PST) From: Nadav Amit To: Ingo Molnar CC: , , "H. Peter Anvin" , Thomas Gleixner , Borislav Petkov , Andy Lutomirski , Nadav Amit , Dave Hansen , Peter Zijlstra , , , , Nadav Amit , Kees Cook , Dave Hansen , Masami Hiramatsu Subject: [PATCH v7 12/14] x86/alternative: Remove the return value of text_poke_*() Date: Tue, 4 Dec 2018 17:34:06 -0800 Message-ID: <20181205013408.47725-13-namit@vmware.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181205013408.47725-1-namit@vmware.com> References: <20181205013408.47725-1-namit@vmware.com> MIME-Version: 1.0 Received-SPF: None (EX13-EDG-OU-002.vmware.com: namit@vmware.com does not designate permitted sender hosts) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP The return value of text_poke_early() and text_poke_bp() is useless. Remove it. Cc: Andy Lutomirski Cc: Kees Cook Cc: Peter Zijlstra Cc: Dave Hansen Cc: Masami Hiramatsu Signed-off-by: Nadav Amit --- arch/x86/include/asm/text-patching.h | 4 ++-- arch/x86/kernel/alternative.c | 11 ++++------- 2 files changed, 6 insertions(+), 9 deletions(-) diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h index a75eed841eed..c90678fd391a 100644 --- a/arch/x86/include/asm/text-patching.h +++ b/arch/x86/include/asm/text-patching.h @@ -18,7 +18,7 @@ static inline void apply_paravirt(struct paravirt_patch_site *start, #define __parainstructions_end NULL #endif -extern void *text_poke_early(void *addr, const void *opcode, size_t len); +extern void text_poke_early(void *addr, const void *opcode, size_t len); /* * Clear and restore the kernel write-protection flag on the local CPU. @@ -37,7 +37,7 @@ extern void *text_poke_early(void *addr, const void *opcode, size_t len); extern void *text_poke(void *addr, const void *opcode, size_t len); extern void *text_poke_kgdb(void *addr, const void *opcode, size_t len); extern int poke_int3_handler(struct pt_regs *regs); -extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler); +extern void text_poke_bp(void *addr, const void *opcode, size_t len, void *handler); extern int after_bootmem; extern __ro_after_init struct mm_struct *poking_mm; extern __ro_after_init unsigned long poking_addr; diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 18415e3b6000..2740ad2c6f21 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -264,7 +264,7 @@ static void __init_or_module add_nops(void *insns, unsigned int len) extern struct alt_instr __alt_instructions[], __alt_instructions_end[]; extern s32 __smp_locks[], __smp_locks_end[]; -void *text_poke_early(void *addr, const void *opcode, size_t len); +void text_poke_early(void *addr, const void *opcode, size_t len); /* * Are we looking at a near JMP with a 1 or 4-byte displacement. @@ -666,8 +666,8 @@ void __init alternative_instructions(void) * instructions. And on the local CPU you need to be protected again NMI or MCE * handlers seeing an inconsistent instruction while you patch. */ -void *__init_or_module text_poke_early(void *addr, const void *opcode, - size_t len) +void __init_or_module text_poke_early(void *addr, const void *opcode, + size_t len) { unsigned long flags; @@ -690,7 +690,6 @@ void *__init_or_module text_poke_early(void *addr, const void *opcode, * that causes hangs on some VIA CPUs. */ } - return addr; } __ro_after_init struct mm_struct *poking_mm; @@ -893,7 +892,7 @@ int poke_int3_handler(struct pt_regs *regs) * replacing opcode * - sync cores */ -void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler) +void text_poke_bp(void *addr, const void *opcode, size_t len, void *handler) { unsigned char int3 = 0xcc; @@ -935,7 +934,5 @@ void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler) * the writing of the new instruction. */ bp_patching_in_progress = false; - - return addr; }