Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932631AbbFHWZy (ORCPT ); Mon, 8 Jun 2015 18:25:54 -0400 Received: from terminus.zytor.com ([198.137.202.10]:43789 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932395AbbFHWZr (ORCPT ); Mon, 8 Jun 2015 18:25:47 -0400 Date: Mon, 8 Jun 2015 15:24:35 -0700 From: tip-bot for Denys Vlasenko Message-ID: Cc: oleg@redhat.com, ast@plumgrid.com, keescook@chromium.org, peterz@infradead.org, torvalds@linux-foundation.org, fweisbec@gmail.com, hpa@zytor.com, rostedt@goodmis.org, akpm@linux-foundation.org, wad@chromium.org, bp@alien8.de, linux-kernel@vger.kernel.org, luto@amacapital.net, dvlasenk@redhat.com, mingo@kernel.org, tglx@linutronix.de Reply-To: rostedt@goodmis.org, hpa@zytor.com, fweisbec@gmail.com, peterz@infradead.org, torvalds@linux-foundation.org, wad@chromium.org, akpm@linux-foundation.org, ast@plumgrid.com, oleg@redhat.com, keescook@chromium.org, mingo@kernel.org, tglx@linutronix.de, bp@alien8.de, dvlasenk@redhat.com, linux-kernel@vger.kernel.org, luto@amacapital.net In-Reply-To: <1433701470-28800-1-git-send-email-dvlasenk@redhat.com> References: <1433701470-28800-1-git-send-email-dvlasenk@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/asm/entry/32: Reinstate clearing of pt_regs-> r8..r11 on EFAULT path Git-Commit-ID: eb47854415825a69b1c578e7487da571227ba25a X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2680 Lines: 75 Commit-ID: eb47854415825a69b1c578e7487da571227ba25a Gitweb: http://git.kernel.org/tip/eb47854415825a69b1c578e7487da571227ba25a Author: Denys Vlasenko AuthorDate: Sun, 7 Jun 2015 20:24:30 +0200 Committer: Ingo Molnar CommitDate: Mon, 8 Jun 2015 23:43:37 +0200 x86/asm/entry/32: Reinstate clearing of pt_regs->r8..r11 on EFAULT path I broke this recently when I changed pt_regs->r8..r11 clearing logic in INT 80 code path. There is a branch from SYSENTER/SYSCALL code to INT 80 code: if we fail to retrieve arg6, we return EFAULT. Before this patch, in this case we don't clear pt_regs->r8..r11. This patch fixes this. The resulting code is smaller and simpler. While at it, remove incorrect comment about syscall dispatching CALL insn: it does not use RIP-relative addressing form (the comment was meant to be "TODO: make this rip-relative", and morphed since then, dropping "TODO"). Signed-off-by: Denys Vlasenko Cc: Alexei Starovoitov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Will Drewry Link: http://lkml.kernel.org/r/1433701470-28800-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/entry/entry_64_compat.S | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 59840e3..5757dde 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -413,9 +413,7 @@ END(entry_SYSCALL_compat) ia32_badarg: ASM_CLAC - movq $-EFAULT, %rax - jmp ia32_sysret - + movq $-EFAULT, RAX(%rsp) ia32_ret_from_sys_call: xorl %eax, %eax /* Do not leak kernel information */ movq %rax, R11(%rsp) @@ -486,9 +484,7 @@ ia32_do_call: cmpq $(IA32_NR_syscalls-1), %rax ja 1f - call *ia32_sys_call_table(, %rax, 8) /* RIP relative */ - -ia32_sysret: + call *ia32_sys_call_table(, %rax, 8) movq %rax, RAX(%rsp) 1: jmp int_ret_from_sys_call -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/