From patchwork Wed Mar 9 00:29:51 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 594714 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id CC9EE14031D; Wed, 9 Mar 2016 11:40:34 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1adSAy-0003Gs-0M; Wed, 09 Mar 2016 00:40:32 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1adS6z-0000pL-6b for kernel-team@lists.ubuntu.com; Wed, 09 Mar 2016 00:36:25 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1adS6y-0003sG-OX; Wed, 09 Mar 2016 00:36:24 +0000 Received: from kamal by fourier with local (Exim 4.86) (envelope-from ) id 1adS6w-00086s-3z; Tue, 08 Mar 2016 16:36:22 -0800 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.19.y-ckt 133/196] s390/compat: correct restore of high gprs on signal return Date: Tue, 8 Mar 2016 16:29:51 -0800 Message-Id: <1457483454-30115-134-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457483454-30115-1-git-send-email-kamal@canonical.com> References: <1457483454-30115-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Cc: Martin Schwidefsky , Kamal Mostafa X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.19.8-ckt16 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Martin Schwidefsky commit 342300cc9cd3428bc6bfe5809bfcc1b9a0f06702 upstream. git commit 8070361799ae1e3f4ef347bd10f0a508ac10acfb "s390: add support for vector extension" broke 31-bit compat processes in regard to signal handling. The restore_sigregs_ext32() function is used to restore the additional elements from the user space signal frame. Among the additional elements are the upper registers halves for 64-bit register support for 31-bit processes. The copy_from_user that is used to retrieve the high-gprs array from the user stack uses an incorrect length, 8 bytes instead of 64 bytes. This causes incorrect upper register halves to get loaded. Signed-off-by: Martin Schwidefsky Signed-off-by: Kamal Mostafa --- arch/s390/kernel/compat_signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c index f564740..020e872 100644 --- a/arch/s390/kernel/compat_signal.c +++ b/arch/s390/kernel/compat_signal.c @@ -293,7 +293,7 @@ static int restore_sigregs_ext32(struct pt_regs *regs, /* Restore high gprs from signal stack */ if (__copy_from_user(&gprs_high, &sregs_ext->gprs_high, - sizeof(&sregs_ext->gprs_high))) + sizeof(sregs_ext->gprs_high))) return -EFAULT; for (i = 0; i < NUM_GPRS; i++) *(__u32 *)®s->gprs[i] = gprs_high[i];