From patchwork Mon Sep 21 14:34:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11790107 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 06FC7112C for ; Mon, 21 Sep 2020 14:36:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7E522226A for ; Mon, 21 Sep 2020 14:36:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="FaYNCJyy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727818AbgIUOf4 (ORCPT ); Mon, 21 Sep 2020 10:35:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727131AbgIUOef (ORCPT ); Mon, 21 Sep 2020 10:34:35 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E11FC061755; Mon, 21 Sep 2020 07:34:34 -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=HMS3wpmHJ08+TjASQ52pDgUhrjMpeVTpap30GBFvOAE=; b=FaYNCJyyME4i3uvXayjfkbvAqj z7tJWyj7bZEt0QdENw0WQ7ww4hTah5nBc2c2ZYSSjANmXgH5MhdZkY2vwwLERNLSdqHgqDMYrbdhA 7Y1IUhSVsaLoqQXCT2FYvxcvjkCIZhdAnxRI60M1X9M+kWvZdxBNBkB6Tt0V4O0MvwNMj3L5s1NAl mjajE+5ZNJkcQm0JWVF9Efr6csREsE6r4SgdAjoDPcoC0HRp6t6pHecWQaQy8HBQFVDyodVwJe0bV Mzfpqr3Grxf3py+y+PrDRx4RHgYCqvX+UhqY27e2Y9L07pRI7fUC4KFQt/YUN1imvNFX0qVSNi19y tDqOx4sw==; 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 1kKMte-0007rq-Pi; Mon, 21 Sep 2020 14:34:27 +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 06/11] iov_iter: handle the compat case in import_iovec Date: Mon, 21 Sep 2020 16:34:29 +0200 Message-Id: <20200921143434.707844-7-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200921143434.707844-1-hch@lst.de> References: <20200921143434.707844-1-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: linux-mips@vger.kernel.org Use in compat_syscall to import either native or the compat iovecs, and remove the now superflous compat_import_iovec, which removes the need for special compat logic in most callers. Only io_uring needs special treatment given that it can call import_iovec from kernel threads acting on behalf of native or compat syscalls. Expose the low-level __import_iovec helper and use it in io_uring to explicitly pick a iovec layout. Signed-off-by: Christoph Hellwig --- block/scsi_ioctl.c | 12 ++---------- drivers/scsi/sg.c | 9 +-------- fs/aio.c | 38 ++++++++++++++------------------------ fs/io_uring.c | 20 ++++++++------------ fs/read_write.c | 6 ++++-- fs/splice.c | 2 +- include/linux/uio.h | 10 +++------- lib/iov_iter.c | 17 +++-------------- mm/process_vm_access.c | 7 ++++--- net/compat.c | 4 ++-- security/keys/compat.c | 5 ++--- 11 files changed, 44 insertions(+), 86 deletions(-) diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index ef722f04f88a93..e08df86866ee5d 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -333,16 +333,8 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk, struct iov_iter i; struct iovec *iov = NULL; -#ifdef CONFIG_COMPAT - if (in_compat_syscall()) - ret = compat_import_iovec(rq_data_dir(rq), - hdr->dxferp, hdr->iovec_count, - 0, &iov, &i); - else -#endif - ret = import_iovec(rq_data_dir(rq), - hdr->dxferp, hdr->iovec_count, - 0, &iov, &i); + ret = import_iovec(rq_data_dir(rq), hdr->dxferp, + hdr->iovec_count, 0, &iov, &i); if (ret < 0) goto out_free_cdb; diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 20472aaaf630a4..bfa8d77322d732 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -1820,14 +1820,7 @@ sg_start_req(Sg_request *srp, unsigned char *cmd) struct iovec *iov = NULL; struct iov_iter i; -#ifdef CONFIG_COMPAT - if (in_compat_syscall()) - res = compat_import_iovec(rw, hp->dxferp, iov_count, - 0, &iov, &i); - else -#endif - res = import_iovec(rw, hp->dxferp, iov_count, - 0, &iov, &i); + res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i); if (res < 0) return res; diff --git a/fs/aio.c b/fs/aio.c index d5ec303855669d..b377f5c2048e18 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1478,8 +1478,7 @@ static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb) } static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, - struct iovec **iovec, bool vectored, bool compat, - struct iov_iter *iter) + struct iovec **iovec, bool vectored, struct iov_iter *iter) { void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; size_t len = iocb->aio_nbytes; @@ -1489,11 +1488,6 @@ static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, *iovec = NULL; return ret; } -#ifdef CONFIG_COMPAT - if (compat) - return compat_import_iovec(rw, buf, len, UIO_FASTIOV, iovec, - iter); -#endif return import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter); } @@ -1517,8 +1511,7 @@ static inline void aio_rw_done(struct kiocb *req, ssize_t ret) } } -static int aio_read(struct kiocb *req, const struct iocb *iocb, - bool vectored, bool compat) +static int aio_read(struct kiocb *req, const struct iocb *iocb, bool vectored) { struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct iov_iter iter; @@ -1535,7 +1528,7 @@ static int aio_read(struct kiocb *req, const struct iocb *iocb, if (unlikely(!file->f_op->read_iter)) return -EINVAL; - ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter); + ret = aio_setup_rw(READ, iocb, &iovec, vectored, &iter); if (ret < 0) return ret; ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter)); @@ -1545,8 +1538,7 @@ static int aio_read(struct kiocb *req, const struct iocb *iocb, return ret; } -static int aio_write(struct kiocb *req, const struct iocb *iocb, - bool vectored, bool compat) +static int aio_write(struct kiocb *req, const struct iocb *iocb, bool vectored) { struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct iov_iter iter; @@ -1563,7 +1555,7 @@ static int aio_write(struct kiocb *req, const struct iocb *iocb, if (unlikely(!file->f_op->write_iter)) return -EINVAL; - ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter); + ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, &iter); if (ret < 0) return ret; ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter)); @@ -1799,8 +1791,7 @@ static int aio_poll(struct aio_kiocb *aiocb, const struct iocb *iocb) } static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, - struct iocb __user *user_iocb, struct aio_kiocb *req, - bool compat) + struct iocb __user *user_iocb, struct aio_kiocb *req) { req->ki_filp = fget(iocb->aio_fildes); if (unlikely(!req->ki_filp)) @@ -1833,13 +1824,13 @@ static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, switch (iocb->aio_lio_opcode) { case IOCB_CMD_PREAD: - return aio_read(&req->rw, iocb, false, compat); + return aio_read(&req->rw, iocb, false); case IOCB_CMD_PWRITE: - return aio_write(&req->rw, iocb, false, compat); + return aio_write(&req->rw, iocb, false); case IOCB_CMD_PREADV: - return aio_read(&req->rw, iocb, true, compat); + return aio_read(&req->rw, iocb, true); case IOCB_CMD_PWRITEV: - return aio_write(&req->rw, iocb, true, compat); + return aio_write(&req->rw, iocb, true); case IOCB_CMD_FSYNC: return aio_fsync(&req->fsync, iocb, false); case IOCB_CMD_FDSYNC: @@ -1852,8 +1843,7 @@ static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, } } -static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, - bool compat) +static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb) { struct aio_kiocb *req; struct iocb iocb; @@ -1882,7 +1872,7 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, if (unlikely(!req)) return -EAGAIN; - err = __io_submit_one(ctx, &iocb, user_iocb, req, compat); + err = __io_submit_one(ctx, &iocb, user_iocb, req); /* Done with the synchronous reference */ iocb_put(req); @@ -1941,7 +1931,7 @@ SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr, break; } - ret = io_submit_one(ctx, user_iocb, false); + ret = io_submit_one(ctx, user_iocb); if (ret) break; } @@ -1983,7 +1973,7 @@ COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id, break; } - ret = io_submit_one(ctx, compat_ptr(user_iocb), true); + ret = io_submit_one(ctx, compat_ptr(user_iocb)); if (ret) break; } diff --git a/fs/io_uring.c b/fs/io_uring.c index 3790c7fe9fee22..ba84ecea7cb1a4 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2837,13 +2837,8 @@ static ssize_t __io_import_iovec(int rw, struct io_kiocb *req, return ret; } -#ifdef CONFIG_COMPAT - if (req->ctx->compat) - return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV, - iovec, iter); -#endif - - return import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter); + return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter, + req->ctx->compat); } static ssize_t io_import_iovec(int rw, struct io_kiocb *req, @@ -4179,8 +4174,9 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req, sr->len); iomsg->iov = NULL; } else { - ret = import_iovec(READ, uiov, iov_len, UIO_FASTIOV, - &iomsg->iov, &iomsg->msg.msg_iter); + ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV, + &iomsg->iov, &iomsg->msg.msg_iter, + false); if (ret > 0) ret = 0; } @@ -4220,9 +4216,9 @@ static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req, sr->len = iomsg->iov[0].iov_len; iomsg->iov = NULL; } else { - ret = compat_import_iovec(READ, uiov, len, UIO_FASTIOV, - &iomsg->iov, - &iomsg->msg.msg_iter); + ret = __import_iovec(READ, (struct iovec __user *)uiov, len, + UIO_FASTIOV, &iomsg->iov, + &iomsg->msg.msg_iter, true); if (ret < 0) return ret; } diff --git a/fs/read_write.c b/fs/read_write.c index e5e891a88442ef..0a68037580b455 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1078,7 +1078,8 @@ static size_t compat_readv(struct file *file, struct iov_iter iter; ssize_t ret; - ret = compat_import_iovec(READ, vec, vlen, UIO_FASTIOV, &iov, &iter); + 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); @@ -1186,7 +1187,8 @@ static size_t compat_writev(struct file *file, struct iov_iter iter; ssize_t ret; - ret = compat_import_iovec(WRITE, vec, vlen, UIO_FASTIOV, &iov, &iter); + 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); diff --git a/fs/splice.c b/fs/splice.c index d7c8a7c4db07ff..132d42b9871f9b 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -1387,7 +1387,7 @@ COMPAT_SYSCALL_DEFINE4(vmsplice, int, fd, const struct compat_iovec __user *, io if (error) return error; - error = compat_import_iovec(type, iov32, nr_segs, + error = import_iovec(type, (struct iovec __user *)iov32, nr_segs, ARRAY_SIZE(iovstack), &iov, &iter); if (error >= 0) { error = do_vmsplice(f.file, &iter, flags); diff --git a/include/linux/uio.h b/include/linux/uio.h index 3835a8a8e9eae0..fff5d49dd0d53e 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -269,13 +269,9 @@ size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp, ssize_t import_iovec(int type, const struct iovec __user * uvector, unsigned nr_segs, unsigned fast_segs, struct iovec **iov, struct iov_iter *i); - -#ifdef CONFIG_COMPAT -struct compat_iovec; -ssize_t compat_import_iovec(int type, const struct compat_iovec __user * uvector, - unsigned nr_segs, unsigned fast_segs, - struct iovec **iov, struct iov_iter *i); -#endif +ssize_t __import_iovec(int type, const struct iovec __user *uvector, + unsigned nr_segs, unsigned fast_segs, struct iovec **iovp, + struct iov_iter *i, bool compat); int import_single_range(int type, void __user *buf, size_t len, struct iovec *iov, struct iov_iter *i); diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 8bfa47b63d39aa..632265178d8737 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -1683,7 +1683,7 @@ static int compat_copy_iovecs_from_user(struct iovec *iov, return ret; } -static ssize_t __import_iovec(int type, const struct iovec __user *uvector, +ssize_t __import_iovec(int type, const struct iovec __user *uvector, unsigned nr_segs, unsigned fast_segs, struct iovec **iovp, struct iov_iter *i, bool compat) { @@ -1793,22 +1793,11 @@ ssize_t import_iovec(int type, const struct iovec __user * uvector, unsigned nr_segs, unsigned fast_segs, struct iovec **iov, struct iov_iter *i) { - return __import_iovec(type, uvector, nr_segs, fast_segs, iov, i, false); + return __import_iovec(type, uvector, nr_segs, fast_segs, iov, i, + in_compat_syscall()); } EXPORT_SYMBOL(import_iovec); -#ifdef CONFIG_COMPAT -ssize_t compat_import_iovec(int type, - const struct compat_iovec __user * uvector, - unsigned nr_segs, unsigned fast_segs, - struct iovec **iov, struct iov_iter *i) -{ - return __import_iovec(type, (const struct iovec __user *)uvector, - nr_segs, fast_segs, iov, i, true); -} -EXPORT_SYMBOL(compat_import_iovec); -#endif - int import_single_range(int rw, void __user *buf, size_t len, struct iovec *iov, struct iov_iter *i) { diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index 40cd502c337534..b759ed264840d8 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -331,13 +331,14 @@ compat_process_vm_rw(compat_pid_t pid, if (flags != 0) return -EINVAL; - rc = compat_import_iovec(dir, lvec, liovcnt, UIO_FASTIOV, &iov_l, &iter_l); + rc = import_iovec(dir, (const struct iovec __user *)iov_l, liovcnt, + UIO_FASTIOV, &iov_l, &iter_l); if (rc < 0) return rc; if (!iov_iter_count(&iter_l)) goto free_iovecs; - rc = compat_import_iovec(CHECK_IOVEC_ONLY, rvec, riovcnt, UIO_FASTIOV, - &iov_r, &iter_r); + rc = import_iovec(CHECK_IOVEC_ONLY, iov_r, riovcnt, UIO_FASTIOV, &iov_r, + &iter_r); if (rc <= 0) goto free_iovecs; diff --git a/net/compat.c b/net/compat.c index 95ce707a30a31d..ddd15af3a2837b 100644 --- a/net/compat.c +++ b/net/compat.c @@ -98,8 +98,8 @@ int get_compat_msghdr(struct msghdr *kmsg, if (err) return err; - err = compat_import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr), - len, UIO_FASTIOV, iov, &kmsg->msg_iter); + err = import_iovec(save_addr ? READ : WRITE, compat_ptr(ptr), len, + UIO_FASTIOV, iov, &kmsg->msg_iter); return err < 0 ? err : 0; } diff --git a/security/keys/compat.c b/security/keys/compat.c index 6ee9d8f6a4a5bb..7ae531db031cf8 100644 --- a/security/keys/compat.c +++ b/security/keys/compat.c @@ -33,9 +33,8 @@ static long compat_keyctl_instantiate_key_iov( if (!_payload_iov) ioc = 0; - ret = compat_import_iovec(WRITE, _payload_iov, ioc, - ARRAY_SIZE(iovstack), &iov, - &from); + ret = import_iovec(WRITE, (const struct iovec __user *)_payload_iov, + ioc, ARRAY_SIZE(iovstack), &iov, &from); if (ret < 0) return ret;