From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-4.7 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 2F7481F4B4 for ; Thu, 15 Oct 2020 17:44:49 +0000 (UTC) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 27E6D395187B; Thu, 15 Oct 2020 17:44:48 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 27E6D395187B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1602783888; bh=oG2fmGIEFjxFWMnINxfF5Uf0xeiGSbiUIAleY8zeJe0=; h=Subject:To:References:Date:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=kcRg29VYvWbA3H1WOnZbU7+dgXhiXLiQ/QluUvoHgGIHLUPNy3kbSt2+11s/KAVUd bKR5om+YAZelt0YhmVtJl3IIxHZc4P6XNvRsa/TWEiQbnzky4HdcryEVvI0HiSsciA /d1u9SFa/OW+KWQJ2R/t9wP5PMhtY7V6PecIRBf8= Received: from mail-qv1-xf44.google.com (mail-qv1-xf44.google.com [IPv6:2607:f8b0:4864:20::f44]) by sourceware.org (Postfix) with ESMTPS id D4B9C3857808 for ; Thu, 15 Oct 2020 17:44:44 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org D4B9C3857808 Received: by mail-qv1-xf44.google.com with SMTP id f5so1508569qvx.6 for ; Thu, 15 Oct 2020 10:44:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=oG2fmGIEFjxFWMnINxfF5Uf0xeiGSbiUIAleY8zeJe0=; b=oyrzlVPYvKbuWehdC1iRKzqmaUaZ2AaMZd02DeD845hyDl1ta0+lOUWs6Ye0KPgXGO W65WUT9lP3gJpdXD6hrCy6SaW1GDmMGmEcz8p9pLvVnpF9z8mKqDvQb8YB+STcIvD85h t7M2P9ud587oP1fTl7ONXSQd1kkZdxcsLOGeVezuNdHijQBtxnr8zzZENeDLOVOpEECI MbuD6VMfzdBeBocuFctYSAAwR9Gp96l/wA1iFAEQVCnNO74VmFepZ+r7hpi5nEdkBiz4 /hbIoBINcl5oPfjdBGm0HsBOnabVLfG+KVDC3SrvFYn3/blVf7C6PIJaQWOmgdLT4I8L 5x5A== X-Gm-Message-State: AOAM531F/zRRcwb3ByAD+LjqCVYXAi+As0JHwHum7zoPOwb3/JHY3hG7 UXNr/ArqFgkZCC6+4gEWOD9UMqmCRq5aTA== X-Google-Smtp-Source: ABdhPJwPvHjto0mVIYaTgDapJ/D7vijIgP4KYydiruk7lor5XE+61dY3ozXcrxzYhXtRSbxEi6GabA== X-Received: by 2002:a0c:e9ca:: with SMTP id q10mr5663260qvo.19.1602783884177; Thu, 15 Oct 2020 10:44:44 -0700 (PDT) Received: from [192.168.1.4] ([177.194.48.209]) by smtp.googlemail.com with ESMTPSA id d14sm1433231qtr.62.2020.10.15.10.44.42 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 15 Oct 2020 10:44:43 -0700 (PDT) Subject: Re: [PATCH] IPC_INFO: Cast shmmax and shmall fields to uintptr_t [BZ #26736] To: "H.J. Lu" References: <20201015151756.514621-1-hjl.tools@gmail.com> <0ec71544-c340-ef47-89c2-fd5a13eabb30@linaro.org> Autocrypt: addr=adhemerval.zanella@linaro.org; prefer-encrypt=mutual; keydata= mQINBFcVGkoBEADiQU2x/cBBmAVf5C2d1xgz6zCnlCefbqaflUBw4hB/bEME40QsrVzWZ5Nq 8kxkEczZzAOKkkvv4pRVLlLn/zDtFXhlcvQRJ3yFMGqzBjofucOrmdYkOGo0uCaoJKPT186L NWp53SACXguFJpnw4ODI64ziInzXQs/rUJqrFoVIlrPDmNv/LUv1OVPKz20ETjgfpg8MNwG6 iMizMefCl+RbtXbIEZ3TE/IaDT/jcOirjv96lBKrc/pAL0h/O71Kwbbp43fimW80GhjiaN2y WGByepnkAVP7FyNarhdDpJhoDmUk9yfwNuIuESaCQtfd3vgKKuo6grcKZ8bHy7IXX1XJj2X/ BgRVhVgMHAnDPFIkXtP+SiarkUaLjGzCz7XkUn4XAGDskBNfbizFqYUQCaL2FdbW3DeZqNIa nSzKAZK7Dm9+0VVSRZXP89w71Y7JUV56xL/PlOE+YKKFdEw+gQjQi0e+DZILAtFjJLoCrkEX w4LluMhYX/X8XP6/C3xW0yOZhvHYyn72sV4yJ1uyc/qz3OY32CRy+bwPzAMAkhdwcORA3JPb kPTlimhQqVgvca8m+MQ/JFZ6D+K7QPyvEv7bQ7M+IzFmTkOCwCJ3xqOD6GjX3aphk8Sr0dq3 4Awlf5xFDAG8dn8Uuutb7naGBd/fEv6t8dfkNyzj6yvc4jpVxwARAQABtElBZGhlbWVydmFs IFphbmVsbGEgTmV0dG8gKExpbmFybyBWUE4gS2V5KSA8YWRoZW1lcnZhbC56YW5lbGxhQGxp bmFyby5vcmc+iQI3BBMBCAAhBQJXFRpKAhsDBQsJCAcDBRUKCQgLBRYCAwEAAh4BAheAAAoJ EKqx7BSnlIjv0e8P/1YOYoNkvJ+AJcNUaM5a2SA9oAKjSJ/M/EN4Id5Ow41ZJS4lUA0apSXW NjQg3VeVc2RiHab2LIB4MxdJhaWTuzfLkYnBeoy4u6njYcaoSwf3g9dSsvsl3mhtuzm6aXFH /Qsauav77enJh99tI4T+58rp0EuLhDsQbnBic/ukYNv7sQV8dy9KxA54yLnYUFqH6pfH8Lly sTVAMyi5Fg5O5/hVV+Z0Kpr+ZocC1YFJkTsNLAW5EIYSP9ftniqaVsim7MNmodv/zqK0IyDB GLLH1kjhvb5+6ySGlWbMTomt/or/uvMgulz0bRS+LUyOmlfXDdT+t38VPKBBVwFMarNuREU2 69M3a3jdTfScboDd2ck1u7l+QbaGoHZQ8ZNUrzgObltjohiIsazqkgYDQzXIMrD9H19E+8fw kCNUlXxjEgH/Kg8DlpoYJXSJCX0fjMWfXywL6ZXc2xyG/hbl5hvsLNmqDpLpc1CfKcA0BkK+ k8R57fr91mTCppSwwKJYO9T+8J+o4ho/CJnK/jBy1pWKMYJPvvrpdBCWq3MfzVpXYdahRKHI ypk8m4QlRlbOXWJ3TDd/SKNfSSrWgwRSg7XCjSlR7PNzNFXTULLB34sZhjrN6Q8NQZsZnMNs TX8nlGOVrKolnQPjKCLwCyu8PhllU8OwbSMKskcD1PSkG6h3r0AquQINBFcVGkoBEACgAdbR Ck+fsfOVwT8zowMiL3l9a2DP3Eeak23ifdZG+8Avb/SImpv0UMSbRfnw/N81IWwlbjkjbGTu oT37iZHLRwYUFmA8fZX0wNDNKQUUTjN6XalJmvhdz9l71H3WnE0wneEM5ahu5V1L1utUWTyh VUwzX1lwJeV3vyrNgI1kYOaeuNVvq7npNR6t6XxEpqPsNc6O77I12XELic2+36YibyqlTJIQ V1SZEbIy26AbC2zH9WqaKyGyQnr/IPbTJ2Lv0dM3RaXoVf+CeK7gB2B+w1hZummD21c1Laua +VIMPCUQ+EM8W9EtX+0iJXxI+wsztLT6vltQcm+5Q7tY+HFUucizJkAOAz98YFucwKefbkTp eKvCfCwiM1bGatZEFFKIlvJ2QNMQNiUrqJBlW9nZp/k7pbG3oStOjvawD9ZbP9e0fnlWJIsj 6c7pX354Yi7kxIk/6gREidHLLqEb/otuwt1aoMPg97iUgDV5mlNef77lWE8vxmlY0FBWIXuZ yv0XYxf1WF6dRizwFFbxvUZzIJp3spAao7jLsQj1DbD2s5+S1BW09A0mI/1DjB6EhNN+4bDB SJCOv/ReK3tFJXuj/HbyDrOdoMt8aIFbe7YFLEExHpSk+HgN05Lg5TyTro8oW7TSMTk+8a5M kzaH4UGXTTBDP/g5cfL3RFPl79ubXwARAQABiQIfBBgBCAAJBQJXFRpKAhsMAAoJEKqx7BSn lIjvI/8P/jg0jl4Tbvg3B5kT6PxJOXHYu9OoyaHLcay6Cd+ZrOd1VQQCbOcgLFbf4Yr+rE9l mYsY67AUgq2QKmVVbn9pjvGsEaz8UmfDnz5epUhDxC6yRRvY4hreMXZhPZ1pbMa6A0a/WOSt AgFj5V6Z4dXGTM/lNManr0HjXxbUYv2WfbNt3/07Db9T+GZkpUotC6iknsTA4rJi6u2ls0W9 1UIvW4o01vb4nZRCj4rni0g6eWoQCGoVDk/xFfy7ZliR5B+3Z3EWRJcQskip/QAHjbLa3pml xAZ484fVxgeESOoaeC9TiBIp0NfH8akWOI0HpBCiBD5xaCTvR7ujUWMvhsX2n881r/hNlR9g fcE6q00qHSPAEgGr1bnFv74/1vbKtjeXLCcRKk3Ulw0bY1OoDxWQr86T2fZGJ/HIZuVVBf3+ gaYJF92GXFynHnea14nFFuFgOni0Mi1zDxYH/8yGGBXvo14KWd8JOW0NJPaCDFJkdS5hu0VY 7vJwKcyHJGxsCLU+Et0mryX8qZwqibJIzu7kUJQdQDljbRPDFd/xmGUFCQiQAncSilYOcxNU EMVCXPAQTteqkvA+gNqSaK1NM9tY0eQ4iJpo+aoX8HAcn4sZzt2pfUB9vQMTBJ2d4+m/qO6+ cFTAceXmIoFsN8+gFN3i8Is3u12u8xGudcBPvpoy4OoG Message-ID: Date: Thu, 15 Oct 2020 14:44:40 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Adhemerval Zanella via Libc-alpha Reply-To: Adhemerval Zanella Cc: GNU C Library Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" On 15/10/2020 14:40, H.J. Lu wrote: > On Thu, Oct 15, 2020 at 10:24 AM Adhemerval Zanella via Libc-alpha > wrote: >> >> >> >> On 15/10/2020 12:17, H.J. Lu via Libc-alpha wrote: >>> On x32, the shmctl (IPC_INFO) syscall returns the x86-64 values for >>> shmmax and shmall. Since x32 is limited to 32-bit address space, >>> shmmax and shmall should be casted to uintptr_t and shmmax should be >>> clamped to INT_MAX only if the size of shmmax is the size of int. >>> --- >>> sysdeps/unix/sysv/linux/shmctl.c | 20 ++++++++++++++++---- >>> sysdeps/unix/sysv/linux/tst-sysvshm-linux.c | 3 ++- >>> 2 files changed, 18 insertions(+), 5 deletions(-) >>> >>> diff --git a/sysdeps/unix/sysv/linux/shmctl.c b/sysdeps/unix/sysv/linux/shmctl.c >>> index 833f013e69..8d34c0e7bf 100644 >>> --- a/sysdeps/unix/sysv/linux/shmctl.c >>> +++ b/sysdeps/unix/sysv/linux/shmctl.c >>> @@ -138,11 +138,11 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf) >>> >>> switch (cmd) >>> { >>> - case IPC_STAT: >>> - case SHM_STAT: >>> - case SHM_STAT_ANY: >>> + case IPC_STAT: >>> + case SHM_STAT: >>> + case SHM_STAT_ANY: >>> #ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T >>> - arg->shm_perm.mode >>= 16; >>> + arg->shm_perm.mode >>= 16; >>> #else >>> /* Old Linux kernel versions might not clear the mode padding. */ >>> if (sizeof ((struct shmid_ds){0}.shm_perm.mode) >>> @@ -153,6 +153,18 @@ __shmctl64 (int shmid, int cmd, struct __shmid64_ds *buf) >>> #if __IPC_TIME64 >>> kshmid64_to_shmid64 (arg, buf); >>> #endif >>> + break; >>> + >>> + case IPC_INFO: >>> + if (sizeof (((struct shminfo *) 0)->shmmax) > sizeof (uintptr_t)) >>> + { >>> + /* Since the address space is limited by the size of uintptr_t, >>> + cast shmmax and shmall to uintptr_t. */ >>> + struct shminfo *shminfo_p = (struct shminfo *) arg; >>> + shminfo_p->shmmax = (uintptr_t) shminfo_p->shmmax; >>> + shminfo_p->shmall = (uintptr_t) shminfo_p->shmall; >>> + } >>> + break; >>> } >>> >>> return ret; >>> diff --git a/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c b/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c >>> index 7128ae2e14..abeeb37a78 100644 >>> --- a/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c >>> +++ b/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c >>> @@ -128,7 +128,8 @@ do_test (void) >>> #if LONG_MAX == INT_MAX >>> /* Kernel explicit clamp the value for shmmax on compat symbol (32-bit >>> binaries running on 64-bit kernels). */ >>> - if (v > INT_MAX) >>> + if (sizeof (((struct shminfo *) 0)->shmmax) == sizeof (int) >>> + && v > INT_MAX) >>> v = INT_MAX; >>> #endif >>> tipcinfo.shmmax = v; >>> >> >> This is semantic change of shmctl for x32, which I really do not oppose >> but I think we should rely on kernel to clamp the value correctly for x32 >> (the shmctl is already rather complex to handle y2038 safeness). >> >> What about changing the testcase to use the expected types for shminfo >> fields (__syscall_ulong_t instead of unsigned long int) and check for >> the expected provided kernel value: >> >> --- >> >> diff --git a/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c b/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c >> index 7128ae2e14..cb32bd522e 100644 >> --- a/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c >> +++ b/sysdeps/unix/sysv/linux/tst-sysvshm-linux.c >> @@ -54,9 +54,9 @@ do_prepare (int argc, char *argv[]) >> >> struct test_shminfo >> { >> - unsigned long int shmall; >> - unsigned long int shmmax; >> - unsigned long int shmmni; >> + __syscall_ulong_t shmall; >> + __syscall_ulong_t shmmax; >> + __syscall_ulong_t shmmni; >> }; >> >> /* It tries to obtain some system-wide SysV shared memory information from >> @@ -128,7 +128,8 @@ do_test (void) >> #if LONG_MAX == INT_MAX >> /* Kernel explicit clamp the value for shmmax on compat symbol (32-bit >> binaries running on 64-bit kernels). */ >> - if (v > INT_MAX) >> + if (sizeof (__syscall_ulong_t) == sizeof (unsigned long int) >> + && v > INT_MAX) >> v = INT_MAX; >> #endif >> tipcinfo.shmmax = v; > > This works. Can you check it in? I will do it.