From patchwork Fri Jul 22 12:41:52 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 9243493 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A4D2D607D3 for ; Fri, 22 Jul 2016 12:42:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 967CA27FA3 for ; Fri, 22 Jul 2016 12:42:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8B5AE27FA4; Fri, 22 Jul 2016 12:42:28 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id F037327D76 for ; Fri, 22 Jul 2016 12:42:27 +0000 (UTC) Received: from localhost ([::1]:47036 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bQZmc-0000iO-VH for patchwork-qemu-devel@patchwork.kernel.org; Fri, 22 Jul 2016 08:42:26 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51869) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bQZmF-0000gN-Qv for qemu-devel@nongnu.org; Fri, 22 Jul 2016 08:42:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bQZmD-0006fK-Vt for qemu-devel@nongnu.org; Fri, 22 Jul 2016 08:42:02 -0400 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:58392) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bQZmD-0006eS-Nz for qemu-devel@nongnu.org; Fri, 22 Jul 2016 08:42:01 -0400 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84_2) (envelope-from ) id 1bQZm5-0004VB-0F; Fri, 22 Jul 2016 13:41:53 +0100 From: Peter Maydell To: qemu-devel@nongnu.org Date: Fri, 22 Jul 2016 13:41:52 +0100 Message-Id: <1469191312-8330-1-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 1.9.1 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:8b0:1d0::2 Subject: [Qemu-devel] [PATCH] linux-user: Handle brk() attempts with very large sizes X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Riku Voipio , patches@linaro.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP In do_brk(), we were inadvertently truncating the size of a requested brk() from the guest by putting it into an 'int' variable. This meant that we would incorrectly report success back to the guest rather than a failed allocation, typically resulting in the guest then segfaulting. Use abi_ulong instead. This fixes a crash in the '31370.cc' test in the gcc libstdc++ test suite (the test case starts by trying to allocate a very large size and reduces the size until the allocation succeeds). Signed-off-by: Peter Maydell --- linux-user/syscall.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index b4dc721..0e98593 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -830,7 +830,7 @@ void target_set_brk(abi_ulong new_brk) abi_long do_brk(abi_ulong new_brk) { abi_long mapped_addr; - int new_alloc_size; + abi_ulong new_alloc_size; DEBUGF_BRK("do_brk(" TARGET_ABI_FMT_lx ") -> ", new_brk);