From patchwork Mon Jun 10 21:20:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 10985521 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3E94C13AD for ; Mon, 10 Jun 2019 21:25:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2D6B427F89 for ; Mon, 10 Jun 2019 21:25:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1FC5828409; Mon, 10 Jun 2019 21:25:58 +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=-2.7 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SUSPICIOUS_RECIPS autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3FB2C28414 for ; Mon, 10 Jun 2019 21:25:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=mcgqSBTtraRgGj4bBEaEVFV6+JCc7iVxVbgWInh3hU0=; b=Rcs1pt+qPt1fQf z8FVQH+Gvhj0i2Gn/2T9VFuJt3ni+tzbNpWGq+dN565qt+cUPexA47qDElxYeC4LW8zinVhuIMJtG DJvxQswzUw/lVAIL3KW0Ne5T5BhoRdCycORDhuroIS1K0hn5Oy7Tsv7Myn1DD1h4Gl82GaxLG0DY0 EGQsc6vvA/qTk73MJvE+4UNriO9ZHjCbzSKIPOq4lDS7WMx3QUgJX8x+sE8NDqLg9vmWgcdMSSodR PLUrDPUvrjjl7OVr1585FpI6Kr4LLNE6XLfGhveuxZAQkkCCximzz4iRPJQCK7nHgWUsxpO/Vnuh7 JEufBashc2PmfTIgNujQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1haRnX-0006Pm-CS; Mon, 10 Jun 2019 21:25:47 +0000 Received: from 089144193064.atnat0002.highway.a1.net ([89.144.193.64] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1haRip-0000p9-Vm; Mon, 10 Jun 2019 21:20:56 +0000 From: Christoph Hellwig To: Greg Ungerer Subject: [PATCH 14/15] binfmt_flat: don't offset the data start Date: Mon, 10 Jun 2019 23:20:14 +0200 Message-Id: <20190610212015.9157-15-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190610212015.9157-1-hch@lst.de> References: <20190610212015.9157-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: uclinux-h8-devel@lists.sourceforge.jp, linux-xtensa@linux-xtensa.org, Michal Simek , linux-c6x-dev@linux-c6x.org, linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Ever since the initial commit of the binfmt_flat shared library support back in the bitkeeper days we've offset the actual in-memory .data start by one field per possible shared library, or 1 in case shared library support isn't enabled. I can't find anything in the loader that actually makes use of it, nor was it present before shared library support it. Signed-off-by: Christoph Hellwig --- fs/binfmt_flat.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index 2c7f32d5435f..e1ccc9f14150 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -572,7 +572,7 @@ static int load_flat_file(struct linux_binprm *bprm, goto err; } - len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); + len = data_len + extra; len = PAGE_ALIGN(len); realdatastart = vm_mmap(NULL, 0, len, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0); @@ -586,9 +586,7 @@ static int load_flat_file(struct linux_binprm *bprm, vm_munmap(textpos, text_len); goto err; } - datapos = ALIGN(realdatastart + - MAX_SHARED_LIBS * sizeof(unsigned long), - FLAT_DATA_ALIGN); + datapos = ALIGN(realdatastart, FLAT_DATA_ALIGN); pr_debug("Allocated data+bss+stack (%u bytes): %lx\n", data_len + bss_len + stack_len, datapos); @@ -618,7 +616,7 @@ static int load_flat_file(struct linux_binprm *bprm, memp_size = len; } else { - len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(u32); + len = text_len + data_len + extra; len = PAGE_ALIGN(len); textpos = vm_mmap(NULL, 0, len, PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0); @@ -633,9 +631,7 @@ static int load_flat_file(struct linux_binprm *bprm, } realdatastart = textpos + ntohl(hdr->data_start); - datapos = ALIGN(realdatastart + - MAX_SHARED_LIBS * sizeof(u32), - FLAT_DATA_ALIGN); + datapos = ALIGN(realdatastart, FLAT_DATA_ALIGN); reloc = (__be32 __user *) (datapos + (ntohl(hdr->reloc_start) - text_len)); @@ -652,8 +648,9 @@ static int load_flat_file(struct linux_binprm *bprm, (text_len + full_data - sizeof(struct flat_hdr)), 0); - memmove((void *) datapos, (void *) realdatastart, - full_data); + if (datapos != realdatastart) + memmove((void *)datapos, (void *)realdatastart, + full_data); #else /* * This is used on MMU systems mainly for testing. @@ -709,8 +706,7 @@ static int load_flat_file(struct linux_binprm *bprm, if (IS_ERR_VALUE(result)) { ret = result; pr_err("Unable to read code+data+bss, errno %d\n", ret); - vm_munmap(textpos, text_len + data_len + extra + - MAX_SHARED_LIBS * sizeof(u32)); + vm_munmap(textpos, text_len + data_len + extra); goto err; } }