From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932931AbaICVX7 (ORCPT ); Wed, 3 Sep 2014 17:23:59 -0400 Received: from mail-ig0-f179.google.com ([209.85.213.179]:58404 "EHLO mail-ig0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932684AbaICVXL (ORCPT ); Wed, 3 Sep 2014 17:23:11 -0400 From: Andrew Pinski To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, pinskia@gmail.com Cc: Andrew Pinski Subject: [PATCH 22/24] ARM64:ILP32: Fix signal return for ILP32 when the user modified the signal stack Date: Wed, 3 Sep 2014 14:19:16 -0700 Message-Id: <1409779158-30963-23-git-send-email-apinski@cavium.com> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1409779158-30963-1-git-send-email-apinski@cavium.com> References: <1409779158-30963-1-git-send-email-apinski@cavium.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the user decided to change the stack_t that was on the stack when returning from the signal handler, the stack_t's padding for ILP32 might be not zero. So we need to use the syscall version of restore_altstack (ilp32_sys_sigaltstack). Signed-off-by: Andrew Pinski --- arch/arm64/kernel/signal.c | 14 ++++++++++++++ 1 files changed, 14 insertions(+), 0 deletions(-) diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index 5311147..6316d54 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -35,6 +35,7 @@ #include #include #include +#include /* * Do a signal return; undo the signal stack. These are aligned to 128-bit. @@ -149,6 +150,19 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs) if (restore_sigframe(regs, frame)) goto badframe; +#ifdef CONFIG_ARM64_ILP32 + /* + * ILP32 has to be handled "special" due to maybe not zeroing out + * the upper 32bits of the pointer if the user changed the frame. + */ + if (is_ilp32_compat_task()) { + if (ilp32_sys_sigaltstack(&frame->uc.uc_stack, + NULL) == -EFAULT) + goto badframe; + return regs->regs[0]; + } +#endif + if (restore_altstack(&frame->uc.uc_stack)) goto badframe; -- 1.7.2.5