From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C37EC433DB for ; Sat, 13 Feb 2021 19:13:53 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6D5C664E3F for ; Sat, 13 Feb 2021 19:13:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D5C664E3F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=vivier.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34396 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lB0MZ-0005Xp-Fv for qemu-devel@archiver.kernel.org; Sat, 13 Feb 2021 14:13:51 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51852) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lB0LX-00052E-5G for qemu-devel@nongnu.org; Sat, 13 Feb 2021 14:12:48 -0500 Received: from mout.kundenserver.de ([217.72.192.73]:45523) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lB0LS-0002zK-4Y for qemu-devel@nongnu.org; Sat, 13 Feb 2021 14:12:45 -0500 Received: from [192.168.100.1] ([82.252.149.54]) by mrelayeu.kundenserver.de (mreue107 [213.165.67.119]) with ESMTPSA (Nemesis) id 1MzyAy-1m84VP45zS-00wzYK; Sat, 13 Feb 2021 20:12:30 +0100 Subject: Re: [PATCH] linux-user: fix O_NONBLOCK in signalfd4() and eventfd2() syscalls To: Helge Deller , qemu-devel@nongnu.org References: <20210210061214.GA221322@ls3530.fritz.box> <5fb8b28c-a78f-2523-067d-bfc4c06e27af@vivier.eu> <2734966e-ab5d-aa38-d3a6-0133e5900457@gmx.de> From: Laurent Vivier Message-ID: <9153ab76-459b-8dc0-6682-445e2692b54e@vivier.eu> Date: Sat, 13 Feb 2021 20:12:28 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 MIME-Version: 1.0 In-Reply-To: <2734966e-ab5d-aa38-d3a6-0133e5900457@gmx.de> Content-Type: text/plain; charset=utf-8 Content-Language: fr Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:JmiNdct09qNwDXAmJJdxwjIU9vanLzKDzjH5jgr02T3V9bu9vy0 dtG4+DwPLjDdnDfF4Z6ofOcoUrvR2TWxbc0mTKGClQzI2vn0aTJcpoW/2koZar3xplvNMTJ gpngCNRjhd4ZkvfdhuLB6OTuewfk4jGdqHeHOQ8QXCD4Cx8eHr3AHKAv7KVbUbA8BfYP0Sj gyK1gCYEQFeSh4UdixYkw== X-UI-Out-Filterresults: notjunk:1;V03:K0:XP7frJP/0Js=:PpT4C2JsisHL8XbVAi0WcE 48I+nqyWlNHE97t7q6oiMeUAHZSa1r8xl1epJy9z95AJHlpS+ZTTb37+NF0HrHqSKdX8XShxL KOr40pkDLKKdQRe4RoIoebPejyghpqhR73ithVTScXKtL1Keje9/E9pi32Yg1NCPMjizun0vL tFgER8nPfTPb95ueSP6c71FeXUw/a1D78qrK9Mpeb4HbIZV0py0MtaiKhxe/QvKd8i1hSnI41 aeFaaj14BMAuH/bEFHDWfOHmKqaICNmg787UgdNgww+CbmCGfhYxWWmSRCiqrWgu/aFcOHH17 icGXLb7x3aJ8cSYTV3j0kZRsb6ggGM/mmMMosQ6cg6MyNedZItJV0J7Occ705/u8ZqUTyujJI hYeKGR3U9DvMqLjQ67+ab/wu8zr4CvyC8zi4LPgH2Oe8ozNzdQ237dkrf48pYgn2xKKXdyOfs eYq1DvNW2w== Received-SPF: none client-ip=217.72.192.73; envelope-from=laurent@vivier.eu; helo=mout.kundenserver.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: John David Anglin , Richard Henderson , =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Le 13/02/2021 à 20:05, Helge Deller a écrit : > On 2/13/21 5:38 PM, Laurent Vivier wrote: >> Le 10/02/2021 à 07:12, Helge Deller a écrit : >>> On the hppa target userspace binaries may call signalfd4() and >>> eventfd2() with an old TARGET_O_NONBLOCK value of 000200004 instead of >>> 000200000 for the "mask" syscall parameter, in which case the current >>> emulation doesn't handle the translation to the native O_NONBLOCK value >>> correctly. >>> >>> The 0x04 bit is not masked out before the new O_NONBLOCK bit is set and >>> as such when calling the native syscall errors out with EINVAL. >>> >>> Fix this by introducing TARGET_O_NONBLOCK_MASK which is used to mask off >>> all possible bits. This define defaults to TARGET_O_NONBLOCK when not >>> defined otherwise, so for all other targets the implementation will >>> behave as before. >>> >>> This patch needs to be applied on top of my previous two patches. >>> >>> Bug was found and patch was verified by using qemu-hppa as debian buildd >>> server on x86_64. >>> >>> Signed-off-by: Helge Deller >>> >>> --- >>> >>> diff --git a/linux-user/hppa/target_fcntl.h b/linux-user/hppa/target_fcntl.h >>> index 08e3a4fcb0..4eb0ec98e2 100644 >>> --- a/linux-user/hppa/target_fcntl.h >>> +++ b/linux-user/hppa/target_fcntl.h >>> @@ -9,6 +9,7 @@ >>>   #define HPPA_TARGET_FCNTL_H >>> >>>   #define TARGET_O_NONBLOCK    000200000 >>> +#define TARGET_O_NONBLOCK_MASK 000200004 /* includes old HP-UX NDELAY flag */ >>>   #define TARGET_O_APPEND      000000010 >>>   #define TARGET_O_CREAT       000000400 /* not fcntl */ >>>   #define TARGET_O_EXCL        000002000 /* not fcntl */ >>> diff --git a/linux-user/syscall.c b/linux-user/syscall.c >>> index 27adee908e..3031aa342f 100644 >>> --- a/linux-user/syscall.c >>> +++ b/linux-user/syscall.c >>> @@ -273,6 +273,11 @@ static type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5,    \ >>>   #define TARGET_NR__llseek TARGET_NR_llseek >>>   #endif >>> >>> +/* some platforms need to mask more bits than just TARGET_O_NONBLOCK */ >>> +#ifndef TARGET_O_NONBLOCK_MASK >>> +#define TARGET_O_NONBLOCK_MASK TARGET_O_NONBLOCK >>> +#endif >>> + >>>   #define __NR_sys_gettid __NR_gettid >>>   _syscall0(int, sys_gettid) >>> >>> @@ -7719,7 +7724,7 @@ static abi_long do_signalfd4(int fd, abi_long mask, int flags) >>>       sigset_t host_mask; >>>       abi_long ret; >>> >>> -    if (flags & ~(TARGET_O_NONBLOCK | TARGET_O_CLOEXEC)) { >>> +    if (flags & ~(TARGET_O_NONBLOCK_MASK | TARGET_O_CLOEXEC)) { >>>           return -TARGET_EINVAL; >>>       } >>>       if (!lock_user_struct(VERIFY_READ, target_mask, mask, 1)) { >>> @@ -12508,7 +12513,7 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, >>>   #if defined(TARGET_NR_eventfd2) >>>       case TARGET_NR_eventfd2: >>>       { >>> -        int host_flags = arg2 & (~(TARGET_O_NONBLOCK | TARGET_O_CLOEXEC)); >>> +        int host_flags = arg2 & (~(TARGET_O_NONBLOCK_MASK | TARGET_O_CLOEXEC)); >>>           if (arg2 & TARGET_O_NONBLOCK) { >>>               host_flags |= O_NONBLOCK; >>>           } >>> >> >> You might also update fcntl_flags_tbl[], the first column is the mask. > > No, I intentionally did not updated the fcntl_flags_tbl[] entry. > The check in target_to_host_bitmask() is: >         if ((target_mask & btp->target_mask) == btp->target_bits) > and the table entry is: >  { TARGET_O_NONBLOCK,  TARGET_O_NONBLOCK,  O_NONBLOCK,  O_NONBLOCK,  }, > > Application may hand in 000200000 *or* 000200004 as value. > So checking (value & 000200000) == 000200000 is correct for both cases. > Yes, you're right. Reviewed-by: Laurent Vivier