From patchwork Wed Sep 23 06:05:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: hch X-Patchwork-Id: 260365 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4E3B2C47423 for ; Wed, 23 Sep 2020 06:06:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 078B0221F0 for ; Wed, 23 Sep 2020 06:06:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="cu8HDs2Z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726841AbgIWGGR (ORCPT ); Wed, 23 Sep 2020 02:06:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726179AbgIWGGF (ORCPT ); Wed, 23 Sep 2020 02:06:05 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A873C0613D2; Tue, 22 Sep 2020 23:06:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=ZJRp28PMlTdViRaEFVh58ely0fCO34dl1prBreJiUZM=; b=cu8HDs2ZfDjgABDofRWrgPjJGG 4gvPVWHdh8kTX69hSVA5cdhQIF6fyifMSpOFraLIYUY/ZyXMwos4TrRSwPO2oJ5qwglKPlUtCXCJS 4vb2t23yio64/yc92MKSD9AZqdANFMljxDDFMKiSerK8MapJ/uc1hU2ZESlaVG6ZjYajzckk5gsit zUCa1veq10ua1GdvWA34RzE2LSsEU5YIZzn+SxnOnSVZbhlE0J+mEvP2fsH0SSaOYTuHyS44OVjJO vco2NzHGw4DZvTyGf8s92/u41mPkfEJp1XvE8XhCgLI/UeeiYxYRypZ+/E6KlYTPoyRxAfxzT4xSh juAGaoiw==; Received: from p4fdb0c34.dip0.t-ipconnect.de ([79.219.12.52] helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKxuf-0003Tn-03; Wed, 23 Sep 2020 06:05:57 +0000 From: Christoph Hellwig To: Alexander Viro Cc: Andrew Morton , Jens Axboe , Arnd Bergmann , David Howells , David Laight , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, io-uring@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH 5/9] fs: remove various compat readv/writev helpers Date: Wed, 23 Sep 2020 08:05:43 +0200 Message-Id: <20200923060547.16903-6-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200923060547.16903-1-hch@lst.de> References: <20200923060547.16903-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Now that import_iovec handles compat iovecs as well, all the duplicated code in the compat readv/writev helpers is not needed. Remove them and switch the compat syscall handlers to use the native helpers. Signed-off-by: Christoph Hellwig --- fs/read_write.c | 179 ++++++++---------------------------------------- 1 file changed, 30 insertions(+), 149 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 0a68037580b455..eab427b7cc0a3f 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1068,226 +1068,107 @@ SYSCALL_DEFINE6(pwritev2, unsigned long, fd, const struct iovec __user *, vec, return do_pwritev(fd, vec, vlen, pos, flags); } +/* + * Various compat syscalls. Note that they all pretend to take a native + * iovec - import_iovec will properly treat those as compat_iovecs based on + * in_compat_syscall(). + */ #ifdef CONFIG_COMPAT -static size_t compat_readv(struct file *file, - const struct compat_iovec __user *vec, - unsigned long vlen, loff_t *pos, rwf_t flags) -{ - struct iovec iovstack[UIO_FASTIOV]; - struct iovec *iov = iovstack; - struct iov_iter iter; - ssize_t ret; - - ret = import_iovec(READ, (const struct iovec __user *)vec, vlen, - UIO_FASTIOV, &iov, &iter); - if (ret >= 0) { - ret = do_iter_read(file, &iter, pos, flags); - kfree(iov); - } - if (ret > 0) - add_rchar(current, ret); - inc_syscr(current); - return ret; -} - -static size_t do_compat_readv(compat_ulong_t fd, - const struct compat_iovec __user *vec, - compat_ulong_t vlen, rwf_t flags) -{ - struct fd f = fdget_pos(fd); - ssize_t ret; - loff_t pos; - - if (!f.file) - return -EBADF; - pos = f.file->f_pos; - ret = compat_readv(f.file, vec, vlen, &pos, flags); - if (ret >= 0) - f.file->f_pos = pos; - fdput_pos(f); - return ret; - -} - COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, compat_ulong_t, vlen) { - return do_compat_readv(fd, vec, vlen, 0); -} - -static long do_compat_preadv64(unsigned long fd, - const struct compat_iovec __user *vec, - unsigned long vlen, loff_t pos, rwf_t flags) -{ - struct fd f; - ssize_t ret; - - if (pos < 0) - return -EINVAL; - f = fdget(fd); - if (!f.file) - return -EBADF; - ret = -ESPIPE; - if (f.file->f_mode & FMODE_PREAD) - ret = compat_readv(f.file, vec, vlen, &pos, flags); - fdput(f); - return ret; + return do_readv(fd, vec, vlen, 0); } #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, unsigned long, vlen, loff_t, pos) { - return do_compat_preadv64(fd, vec, vlen, pos, 0); + return do_preadv(fd, vec, vlen, pos, 0); } #endif COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, compat_ulong_t, vlen, u32, pos_low, u32, pos_high) { loff_t pos = ((loff_t)pos_high << 32) | pos_low; - return do_compat_preadv64(fd, vec, vlen, pos, 0); + return do_preadv(fd, vec, vlen, pos, 0); } #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64V2 COMPAT_SYSCALL_DEFINE5(preadv64v2, unsigned long, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, unsigned long, vlen, loff_t, pos, rwf_t, flags) { if (pos == -1) - return do_compat_readv(fd, vec, vlen, flags); - - return do_compat_preadv64(fd, vec, vlen, pos, flags); + return do_readv(fd, vec, vlen, flags); + return do_preadv(fd, vec, vlen, pos, flags); } #endif COMPAT_SYSCALL_DEFINE6(preadv2, compat_ulong_t, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, compat_ulong_t, vlen, u32, pos_low, u32, pos_high, rwf_t, flags) { loff_t pos = ((loff_t)pos_high << 32) | pos_low; if (pos == -1) - return do_compat_readv(fd, vec, vlen, flags); - - return do_compat_preadv64(fd, vec, vlen, pos, flags); -} - -static size_t compat_writev(struct file *file, - const struct compat_iovec __user *vec, - unsigned long vlen, loff_t *pos, rwf_t flags) -{ - struct iovec iovstack[UIO_FASTIOV]; - struct iovec *iov = iovstack; - struct iov_iter iter; - ssize_t ret; - - ret = import_iovec(WRITE, (const struct iovec __user *)vec, vlen, - UIO_FASTIOV, &iov, &iter); - if (ret >= 0) { - file_start_write(file); - ret = do_iter_write(file, &iter, pos, flags); - file_end_write(file); - kfree(iov); - } - if (ret > 0) - add_wchar(current, ret); - inc_syscw(current); - return ret; -} - -static size_t do_compat_writev(compat_ulong_t fd, - const struct compat_iovec __user* vec, - compat_ulong_t vlen, rwf_t flags) -{ - struct fd f = fdget_pos(fd); - ssize_t ret; - loff_t pos; - - if (!f.file) - return -EBADF; - pos = f.file->f_pos; - ret = compat_writev(f.file, vec, vlen, &pos, flags); - if (ret >= 0) - f.file->f_pos = pos; - fdput_pos(f); - return ret; + return do_readv(fd, vec, vlen, flags); + return do_preadv(fd, vec, vlen, pos, flags); } COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, - const struct compat_iovec __user *, vec, + const struct iovec __user *, vec, compat_ulong_t, vlen) { - return do_compat_writev(fd, vec, vlen, 0); -} - -static long do_compat_pwritev64(unsigned long fd, - const struct compat_iovec __user *vec, - unsigned long vlen, loff_t pos, rwf_t flags) -{ - struct fd f; - ssize_t ret; - - if (pos < 0) - return -EINVAL; - f = fdget(fd); - if (!f.file) - return -EBADF; - ret = -ESPIPE; - if (f.file->f_mode & FMODE_PWRITE) - ret = compat_writev(f.file, vec, vlen, &pos, flags); - fdput(f); - return ret; + return do_writev(fd, vec, vlen, 0); } #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64 COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, unsigned long, vlen, loff_t, pos) { - return do_compat_pwritev64(fd, vec, vlen, pos, 0); + return do_pwritev(fd, vec, vlen, pos, 0); } #endif COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *,vec, compat_ulong_t, vlen, u32, pos_low, u32, pos_high) { loff_t pos = ((loff_t)pos_high << 32) | pos_low; - return do_compat_pwritev64(fd, vec, vlen, pos, 0); + return do_pwritev(fd, vec, vlen, pos, 0); } #ifdef __ARCH_WANT_COMPAT_SYS_PWRITEV64V2 COMPAT_SYSCALL_DEFINE5(pwritev64v2, unsigned long, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *, vec, unsigned long, vlen, loff_t, pos, rwf_t, flags) { if (pos == -1) - return do_compat_writev(fd, vec, vlen, flags); - - return do_compat_pwritev64(fd, vec, vlen, pos, flags); + return do_writev(fd, vec, vlen, flags); + return do_pwritev(fd, vec, vlen, pos, flags); } #endif COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd, - const struct compat_iovec __user *,vec, + const struct iovec __user *,vec, compat_ulong_t, vlen, u32, pos_low, u32, pos_high, rwf_t, flags) { loff_t pos = ((loff_t)pos_high << 32) | pos_low; if (pos == -1) - return do_compat_writev(fd, vec, vlen, flags); - - return do_compat_pwritev64(fd, vec, vlen, pos, flags); + return do_writev(fd, vec, vlen, flags); + return do_pwritev(fd, vec, vlen, pos, flags); } - -#endif +#endif /* CONFIG_COMPAT */ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, size_t count, loff_t max)