From patchwork Mon Aug 17 07:32:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345725 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVQzM6htyz9sTK for ; Mon, 17 Aug 2020 17:44:15 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=ULgPyG8A; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVQzM4R14zDqLT for ; Mon, 17 Aug 2020 17:44:15 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=casper.srs.infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=batv+1cabf852a0fb828109f5+6203+infradead.org+hch@casper.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=ULgPyG8A; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BVQjl3BNRzDqN5 for ; Mon, 17 Aug 2020 17:32:27 +1000 (AEST) 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=bPO6IUsgQ1dooQn8lqNrZ8txirq2bFGwte1YnA3ccwk=; b=ULgPyG8AIdpi54WFRLGQa3atjG MYcmUn91T2ZJwQ8XUjt9xRibemgLD7hIV+9q374K0MCkC0goKr1Y5e6cPl974kSIuI9du3LtRhqWy pVNlGGcYWdlFvV35a8J+rXDvK/p4cY4tcFx0JloEF90rwLpx6aRcRrKuOjirQ9xAKtPSPbpuRxs7c 3Ey2vwIhY4owqJn2UjpCnCdSPT4bw5VuudP/c4hvH+V44EHWcyL4DPUp+UiUSngAzDKo4/Iu/3U4j qumfNWtUCBhkIE77s5aYJXDpSNz0oppHKsoMsQuY93PpZh7c4n94SxD6zUNW0R+Mw0/+U5Ii6zhDS k6IPCgFQ==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zcu-0000uv-IA; Mon, 17 Aug 2020 07:32:17 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 01/11] mem: remove duplicate ops for /dev/zero and /dev/null Date: Mon, 17 Aug 2020 09:32:02 +0200 Message-Id: <20200817073212.830069-2-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" There is no good reason to implement both the traditional ->read and ->write as well as the iter based ops. So implement just the iter based ones. Suggested-by: Al Viro Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- drivers/char/mem.c | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 687d4af6945d36..14851f36787372 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -670,18 +670,6 @@ static ssize_t write_port(struct file *file, const char __user *buf, return tmp-buf; } -static ssize_t read_null(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - return 0; -} - -static ssize_t write_null(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - return count; -} - static ssize_t read_iter_null(struct kiocb *iocb, struct iov_iter *to) { return 0; @@ -872,7 +860,6 @@ static int open_port(struct inode *inode, struct file *filp) #define zero_lseek null_lseek #define full_lseek null_lseek -#define write_zero write_null #define write_iter_zero write_iter_null #define open_mem open_port #define open_kmem open_mem @@ -903,8 +890,6 @@ static const struct file_operations __maybe_unused kmem_fops = { static const struct file_operations null_fops = { .llseek = null_lseek, - .read = read_null, - .write = write_null, .read_iter = read_iter_null, .write_iter = write_iter_null, .splice_write = splice_write_null, @@ -919,7 +904,6 @@ static const struct file_operations __maybe_unused port_fops = { static const struct file_operations zero_fops = { .llseek = zero_lseek, - .write = write_zero, .read_iter = read_iter_zero, .write_iter = write_iter_zero, .mmap = mmap_zero, From patchwork Mon Aug 17 07:32:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345712 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVQrx1wclz9sPC for ; Mon, 17 Aug 2020 17:38:41 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=kSRi3/Zh; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVQrx0ykhzDqQx for ; 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Mon, 17 Aug 2020 17:32:27 +1000 (AEST) 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=QasMFseGaRF0U1kWB5Xe6wtKgMVA74LxfHcevvVwJ50=; b=kSRi3/ZhCe5rLY+QWEuAxfVXDC vSLRm/IAuUtN5r5o8S9nstvs5idmxbq1PXUWIq42SlIf+JCdZqL1j13K4BMwkNFcc9GTGnq2Jc16k 1tkT6F1DweJWIUS/zdndhTeSoZA1Smp0s9ynmPkNpxA7lEbjk7+Kzzu5Zffmz2FjmwR/f7tCGQBpm Lw+pCNcQZsdZO0SJM13RQxHSavHuYcIB8nAXTKlLL4J4k4aGFJxEnI38DEy0dOxS6puuLs8V7sJP7 mZMC2iAajfgtxnMWgRfl8dMqzlY0FGE09cx6YRaZmivDVN5XnXsw6DBKRl9aMjYyKFsF6EvcdYwgT wDYYYGkg==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zcw-0000vB-1t; Mon, 17 Aug 2020 07:32:18 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 02/11] fs: don't allow kernel reads and writes without iter ops Date: Mon, 17 Aug 2020 09:32:03 +0200 Message-Id: <20200817073212.830069-3-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Don't allow calling ->read or ->write with set_fs as a preparation for killing off set_fs. All the instances that we use kernel_read/write on are using the iter ops already. If a file has both the regular ->read/->write methods and the iter variants those could have different semantics for messed up enough drivers. Also fails the kernel access to them in that case. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- fs/read_write.c | 67 +++++++++++++++++++++++++++++++------------------ 1 file changed, 42 insertions(+), 25 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 5db58b8c78d0dd..702c4301d9eb6b 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -419,27 +419,41 @@ static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, lo return ret; } +static int warn_unsupported(struct file *file, const char *op) +{ + pr_warn_ratelimited( + "kernel %s not supported for file %pD4 (pid: %d comm: %.20s)\n", + op, file, current->pid, current->comm); + return -EINVAL; +} + ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos) { - mm_segment_t old_fs = get_fs(); + struct kvec iov = { + .iov_base = buf, + .iov_len = min_t(size_t, count, MAX_RW_COUNT), + }; + struct kiocb kiocb; + struct iov_iter iter; ssize_t ret; if (WARN_ON_ONCE(!(file->f_mode & FMODE_READ))) return -EINVAL; if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; + /* + * Also fail if ->read_iter and ->read are both wired up as that + * implies very convoluted semantics. + */ + if (unlikely(!file->f_op->read_iter || file->f_op->read)) + return warn_unsupported(file, "read"); - if (count > MAX_RW_COUNT) - count = MAX_RW_COUNT; - set_fs(KERNEL_DS); - if (file->f_op->read) - ret = file->f_op->read(file, (void __user *)buf, count, pos); - else if (file->f_op->read_iter) - ret = new_sync_read(file, (void __user *)buf, count, pos); - else - ret = -EINVAL; - set_fs(old_fs); + init_sync_kiocb(&kiocb, file); + kiocb.ki_pos = *pos; + iov_iter_kvec(&iter, READ, &iov, 1, iov.iov_len); + ret = file->f_op->read_iter(&kiocb, &iter); if (ret > 0) { + *pos = kiocb.ki_pos; fsnotify_access(file); add_rchar(current, ret); } @@ -510,28 +524,31 @@ static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t /* caller is responsible for file_start_write/file_end_write */ ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t *pos) { - mm_segment_t old_fs; - const char __user *p; + struct kvec iov = { + .iov_base = (void *)buf, + .iov_len = min_t(size_t, count, MAX_RW_COUNT), + }; + struct kiocb kiocb; + struct iov_iter iter; ssize_t ret; if (WARN_ON_ONCE(!(file->f_mode & FMODE_WRITE))) return -EBADF; if (!(file->f_mode & FMODE_CAN_WRITE)) return -EINVAL; + /* + * Also fail if ->write_iter and ->write are both wired up as that + * implies very convoluted semantics. + */ + if (unlikely(!file->f_op->write_iter || file->f_op->write)) + return warn_unsupported(file, "write"); - old_fs = get_fs(); - set_fs(KERNEL_DS); - p = (__force const char __user *)buf; - if (count > MAX_RW_COUNT) - count = MAX_RW_COUNT; - if (file->f_op->write) - ret = file->f_op->write(file, p, count, pos); - else if (file->f_op->write_iter) - ret = new_sync_write(file, p, count, pos); - else - ret = -EINVAL; - set_fs(old_fs); + init_sync_kiocb(&kiocb, file); + kiocb.ki_pos = *pos; + iov_iter_kvec(&iter, WRITE, &iov, 1, iov.iov_len); + ret = file->f_op->write_iter(&kiocb, &iter); if (ret > 0) { + *pos = kiocb.ki_pos; fsnotify_modify(file); add_wchar(current, ret); } From patchwork Mon Aug 17 07:32:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345711 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVQpw0pplz9sPC for ; Mon, 17 Aug 2020 17:36:56 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=DipkJ9iW; 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Mon, 17 Aug 2020 17:32:27 +1000 (AEST) 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=AV1nnDyoAteGW1xDXxiglssfIjdsAGpHVPepm5P0AyM=; b=DipkJ9iW0iJWxipjU4+E9Ha9y4 U6PM+vLkZOuCGUnz6zz6ZKCIfHs4r1PRtGQNb9EGge9BoRJ5M2jqM96i86E+xA4PNTxPyPDN1Xbur cYkUlnhvGW3mTeNGRU4fu2RfKYvZCSfNWLfYloPxpfKdtFiA0rNA2Xynom0xejk6f+eZUWoyaBMOG DzxV4YljSgU/+A+S8DUY3l6WfMjpmuXZH4yuJsqOP7tZznJkTmUSnc9b1VrM8K+nvNG9TL0TBYli6 i6Xg+ocYC9IHt3ADq/WmGYcqg2/RtJxaszBbfRpA6CHEDu1O/SRdTjQd1FmM2IEkgAMdUiWuBUz1W wNej4rsQ==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zcx-0000vI-AH; Mon, 17 Aug 2020 07:32:19 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 03/11] fs: don't allow splice read/write without explicit ops Date: Mon, 17 Aug 2020 09:32:04 +0200 Message-Id: <20200817073212.830069-4-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" default_file_splice_write is the last piece of generic code that uses set_fs to make the uaccess routines operate on kernel pointers. It implements a "fallback loop" for splicing from files that do not actually provide a proper splice_read method. The usual file systems and other high bandwith instances all provide a ->splice_read, so this just removes support for various device drivers and procfs/debugfs files. If splice support for any of those turns out to be important it can be added back by switching them to the iter ops and using generic_file_splice_read. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- fs/read_write.c | 2 +- fs/splice.c | 130 +++++---------------------------------------- include/linux/fs.h | 2 - 3 files changed, 15 insertions(+), 119 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 702c4301d9eb6b..8c61f67453e3d3 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1077,7 +1077,7 @@ ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos, } EXPORT_SYMBOL(vfs_iter_write); -ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, +static ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, unsigned long vlen, loff_t *pos, rwf_t flags) { struct iovec iovstack[UIO_FASTIOV]; diff --git a/fs/splice.c b/fs/splice.c index d7c8a7c4db07ff..412df7b48f9eb7 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -342,89 +342,6 @@ const struct pipe_buf_operations nosteal_pipe_buf_ops = { }; EXPORT_SYMBOL(nosteal_pipe_buf_ops); -static ssize_t kernel_readv(struct file *file, const struct kvec *vec, - unsigned long vlen, loff_t offset) -{ - mm_segment_t old_fs; - loff_t pos = offset; - ssize_t res; - - old_fs = get_fs(); - set_fs(KERNEL_DS); - /* The cast to a user pointer is valid due to the set_fs() */ - res = vfs_readv(file, (const struct iovec __user *)vec, vlen, &pos, 0); - set_fs(old_fs); - - return res; -} - -static ssize_t default_file_splice_read(struct file *in, loff_t *ppos, - struct pipe_inode_info *pipe, size_t len, - unsigned int flags) -{ - struct kvec *vec, __vec[PIPE_DEF_BUFFERS]; - struct iov_iter to; - struct page **pages; - unsigned int nr_pages; - unsigned int mask; - size_t offset, base, copied = 0; - ssize_t res; - int i; - - if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) - return -EAGAIN; - - /* - * Try to keep page boundaries matching to source pagecache ones - - * it probably won't be much help, but... - */ - offset = *ppos & ~PAGE_MASK; - - iov_iter_pipe(&to, READ, pipe, len + offset); - - res = iov_iter_get_pages_alloc(&to, &pages, len + offset, &base); - if (res <= 0) - return -ENOMEM; - - nr_pages = DIV_ROUND_UP(res + base, PAGE_SIZE); - - vec = __vec; - if (nr_pages > PIPE_DEF_BUFFERS) { - vec = kmalloc_array(nr_pages, sizeof(struct kvec), GFP_KERNEL); - if (unlikely(!vec)) { - res = -ENOMEM; - goto out; - } - } - - mask = pipe->ring_size - 1; - pipe->bufs[to.head & mask].offset = offset; - pipe->bufs[to.head & mask].len -= offset; - - for (i = 0; i < nr_pages; i++) { - size_t this_len = min_t(size_t, len, PAGE_SIZE - offset); - vec[i].iov_base = page_address(pages[i]) + offset; - vec[i].iov_len = this_len; - len -= this_len; - offset = 0; - } - - res = kernel_readv(in, vec, nr_pages, *ppos); - if (res > 0) { - copied = res; - *ppos += res; - } - - if (vec != __vec) - kfree(vec); -out: - for (i = 0; i < nr_pages; i++) - put_page(pages[i]); - kvfree(pages); - iov_iter_advance(&to, copied); /* truncates and discards */ - return res; -} - /* * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos' * using sendpage(). Return the number of bytes sent. @@ -788,33 +705,6 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out, EXPORT_SYMBOL(iter_file_splice_write); -static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf, - struct splice_desc *sd) -{ - int ret; - void *data; - loff_t tmp = sd->pos; - - data = kmap(buf->page); - ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp); - kunmap(buf->page); - - return ret; -} - -static ssize_t default_file_splice_write(struct pipe_inode_info *pipe, - struct file *out, loff_t *ppos, - size_t len, unsigned int flags) -{ - ssize_t ret; - - ret = splice_from_pipe(pipe, out, ppos, len, flags, write_pipe_buf); - if (ret > 0) - *ppos += ret; - - return ret; -} - /** * generic_splice_sendpage - splice data from a pipe to a socket * @pipe: pipe to splice from @@ -836,15 +726,23 @@ ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out, EXPORT_SYMBOL(generic_splice_sendpage); +static int warn_unsupported(struct file *file, const char *op) +{ + pr_debug_ratelimited( + "splice %s not supported for file %pD4 (pid: %d comm: %.20s)\n", + op, file, current->pid, current->comm); + return -EINVAL; +} + /* * Attempt to initiate a splice from pipe to file. */ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags) { - if (out->f_op->splice_write) - return out->f_op->splice_write(pipe, out, ppos, len, flags); - return default_file_splice_write(pipe, out, ppos, len, flags); + if (unlikely(!out->f_op->splice_write)) + return warn_unsupported(out, "write"); + return out->f_op->splice_write(pipe, out, ppos, len, flags); } /* @@ -866,9 +764,9 @@ static long do_splice_to(struct file *in, loff_t *ppos, if (unlikely(len > MAX_RW_COUNT)) len = MAX_RW_COUNT; - if (in->f_op->splice_read) - return in->f_op->splice_read(in, ppos, pipe, len, flags); - return default_file_splice_read(in, ppos, pipe, len, flags); + if (unlikely(!in->f_op->splice_read)) + return warn_unsupported(in, "read"); + return in->f_op->splice_read(in, ppos, pipe, len, flags); } /** diff --git a/include/linux/fs.h b/include/linux/fs.h index e019ea2f1347e6..d33cc3e8ed410b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1894,8 +1894,6 @@ ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); -extern ssize_t vfs_readv(struct file *, const struct iovec __user *, - unsigned long, loff_t *, rwf_t); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, From patchwork Mon Aug 17 07:32:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345715 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVQxP1q8Xz9sPC for ; Mon, 17 Aug 2020 17:42:33 +1000 (AEST) Authentication-Results: ozlabs.org; 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Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zcy-0000ve-NC; Mon, 17 Aug 2020 07:32:21 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 04/11] uaccess: add infrastructure for kernel builds with set_fs() Date: Mon, 17 Aug 2020 09:32:05 +0200 Message-Id: <20200817073212.830069-5-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Add a CONFIG_SET_FS option that is selected by architecturess that implement set_fs, which is all of them initially. If the option is not set stubs for routines related to overriding the address space are provided so that architectures can start to opt out of providing set_fs. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- arch/Kconfig | 3 +++ arch/alpha/Kconfig | 1 + arch/arc/Kconfig | 1 + arch/arm/Kconfig | 1 + arch/arm64/Kconfig | 1 + arch/c6x/Kconfig | 1 + arch/csky/Kconfig | 1 + arch/h8300/Kconfig | 1 + arch/hexagon/Kconfig | 1 + arch/ia64/Kconfig | 1 + arch/m68k/Kconfig | 1 + arch/microblaze/Kconfig | 1 + arch/mips/Kconfig | 1 + arch/nds32/Kconfig | 1 + arch/nios2/Kconfig | 1 + arch/openrisc/Kconfig | 1 + arch/parisc/Kconfig | 1 + arch/powerpc/Kconfig | 1 + arch/riscv/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/sh/Kconfig | 1 + arch/sparc/Kconfig | 1 + arch/um/Kconfig | 1 + arch/x86/Kconfig | 1 + arch/xtensa/Kconfig | 1 + include/linux/uaccess.h | 18 ++++++++++++++++++ 26 files changed, 45 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index af14a567b493fc..3fab619a6aa51a 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -24,6 +24,9 @@ config KEXEC_ELF config HAVE_IMA_KEXEC bool +config SET_FS + bool + config HOTPLUG_SMT bool diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index 9c5f06e8eb9bc0..d6e9fc7a7b19e2 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -39,6 +39,7 @@ config ALPHA select OLD_SIGSUSPEND select CPU_NO_EFFICIENT_FFS if !ALPHA_EV67 select MMU_GATHER_NO_RANGE + select SET_FS help The Alpha is a 64-bit general-purpose processor designed and marketed by the Digital Equipment Corporation of blessed memory, diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index ba00c4e1e1c271..c49f5754a11e40 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -48,6 +48,7 @@ config ARC select PCI_SYSCALL if PCI select PERF_USE_VMALLOC if ARC_CACHE_VIPT_ALIASING select HAVE_ARCH_JUMP_LABEL if ISA_ARCV2 && !CPU_ENDIAN_BE32 + select SET_FS config ARCH_HAS_CACHE_LINE_SIZE def_bool y diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index e00d94b1665876..87e1478a42dc4f 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -118,6 +118,7 @@ config ARM select PCI_SYSCALL if PCI select PERF_USE_VMALLOC select RTC_LIB + select SET_FS select SYS_SUPPORTS_APM_EMULATION # Above selects are sorted alphabetically; please add new ones # according to that. Thanks. diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6d232837cbeee8..fbd9e35bef096f 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -192,6 +192,7 @@ config ARM64 select PCI_SYSCALL if PCI select POWER_RESET select POWER_SUPPLY + select SET_FS select SPARSE_IRQ select SWIOTLB select SYSCTL_EXCEPTION_TRACE diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig index 6444ebfd06a665..48d66bf0465d68 100644 --- a/arch/c6x/Kconfig +++ b/arch/c6x/Kconfig @@ -22,6 +22,7 @@ config C6X select GENERIC_CLOCKEVENTS select MODULES_USE_ELF_RELA select MMU_GATHER_NO_RANGE if MMU + select SET_FS config MMU def_bool n diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index 3d5afb5f568543..2836f6e76fdb2d 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -78,6 +78,7 @@ config CSKY select PCI_DOMAINS_GENERIC if PCI select PCI_SYSCALL if PCI select PCI_MSI if PCI + select SET_FS config LOCKDEP_SUPPORT def_bool y diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index d11666d538fea8..7945de067e9fcc 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -25,6 +25,7 @@ config H8300 select HAVE_ARCH_KGDB select HAVE_ARCH_HASH select CPU_NO_EFFICIENT_FFS + select SET_FS select UACCESS_MEMCPY config CPU_BIG_ENDIAN diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig index 667cfc511cf999..f2afabbadd430e 100644 --- a/arch/hexagon/Kconfig +++ b/arch/hexagon/Kconfig @@ -31,6 +31,7 @@ config HEXAGON select GENERIC_CLOCKEVENTS_BROADCAST select MODULES_USE_ELF_RELA select GENERIC_CPU_DEVICES + select SET_FS help Qualcomm Hexagon is a processor architecture designed for high performance and low power across a wide variety of applications. diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 5b4ec80bf5863a..22a6853840e235 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -56,6 +56,7 @@ config IA64 select NEED_DMA_MAP_STATE select NEED_SG_DMA_LENGTH select NUMA if !FLATMEM + select SET_FS default y help The Itanium Processor Family is Intel's 64-bit successor to diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 6f2f38d05772ab..dcf4ae8c9b215f 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -32,6 +32,7 @@ config M68K select OLD_SIGSUSPEND3 select OLD_SIGACTION select MMU_GATHER_NO_RANGE if MMU + select SET_FS config CPU_BIG_ENDIAN def_bool y diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index d262ac0c8714bd..7e3d4583abf3e6 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -46,6 +46,7 @@ config MICROBLAZE select CPU_NO_EFFICIENT_FFS select MMU_GATHER_NO_RANGE if MMU select SPARSE_IRQ + select SET_FS # Endianness selection choice diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index c95fa3a2484cf0..fbc26391b588f8 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -87,6 +87,7 @@ config MIPS select MODULES_USE_ELF_RELA if MODULES && 64BIT select PERF_USE_VMALLOC select RTC_LIB + select SET_FS select SYSCTL_EXCEPTION_TRACE select VIRT_TO_BUS diff --git a/arch/nds32/Kconfig b/arch/nds32/Kconfig index e30298e99e1bdf..e8e541fd2267d0 100644 --- a/arch/nds32/Kconfig +++ b/arch/nds32/Kconfig @@ -48,6 +48,7 @@ config NDS32 select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FTRACE_MCOUNT_RECORD select HAVE_DYNAMIC_FTRACE + select SET_FS help Andes(nds32) Linux support. diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig index c6645141bb2a88..c7c6ba6bec9dfc 100644 --- a/arch/nios2/Kconfig +++ b/arch/nios2/Kconfig @@ -27,6 +27,7 @@ config NIOS2 select USB_ARCH_HAS_HCD if USB_SUPPORT select CPU_NO_EFFICIENT_FFS select MMU_GATHER_NO_RANGE if MMU + select SET_FS config GENERIC_CSUM def_bool y diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig index 7e94fe37cb2fdf..6233c62931803f 100644 --- a/arch/openrisc/Kconfig +++ b/arch/openrisc/Kconfig @@ -39,6 +39,7 @@ config OPENRISC select ARCH_WANT_FRAME_POINTERS select GENERIC_IRQ_MULTI_HANDLER select MMU_GATHER_NO_RANGE if MMU + select SET_FS config CPU_BIG_ENDIAN def_bool y diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 3b0f53dd70bc9b..be70af482b5a9a 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -63,6 +63,7 @@ config PARISC select HAVE_FTRACE_MCOUNT_RECORD if HAVE_DYNAMIC_FTRACE select HAVE_KPROBES_ON_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_REGS + select SET_FS help The PA-RISC microprocessor is designed by Hewlett-Packard and used diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 1f48bbfb3ce99d..3f09d6fdf89405 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -249,6 +249,7 @@ config PPC select PCI_SYSCALL if PCI select PPC_DAWR if PPC64 select RTC_LIB + select SET_FS select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 7b590552914664..6e05a94f808a5a 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -82,6 +82,7 @@ config RISCV select PCI_MSI if PCI select RISCV_INTC select RISCV_TIMER + select SET_FS select SPARSEMEM_STATIC if 32BIT select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 3d86e12e8e3c21..fd81385a7787cb 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -185,6 +185,7 @@ config S390 select OLD_SIGSUSPEND3 select PCI_DOMAINS if PCI select PCI_MSI if PCI + select SET_FS select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index d20927128fce05..2bd1653f3b3fea 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -71,6 +71,7 @@ config SUPERH select PERF_EVENTS select PERF_USE_VMALLOC select RTC_LIB + select SET_FS select SPARSE_IRQ help The SuperH is a RISC processor targeted for use in embedded systems diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index efeff2c896a544..3e0cf0319a278a 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -49,6 +49,7 @@ config SPARC select LOCKDEP_SMALL if LOCKDEP select NEED_DMA_MAP_STATE select NEED_SG_DMA_LENGTH + select SET_FS config SPARC32 def_bool !64BIT diff --git a/arch/um/Kconfig b/arch/um/Kconfig index eb51fec759484a..3aefcd81566809 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -19,6 +19,7 @@ config UML select GENERIC_CPU_DEVICES select GENERIC_CLOCKEVENTS select HAVE_GCC_PLUGINS + select SET_FS select TTY # Needed for line.c config MMU diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7101ac64bb209d..f85c13355732fe 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -237,6 +237,7 @@ config X86 select HAVE_ARCH_KCSAN if X86_64 select X86_FEATURE_NAMES if PROC_FS select PROC_PID_ARCH_STATUS if PROC_FS + select SET_FS imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI config INSTRUCTION_DECODER diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index e997e0119c0251..94bad4d66b4bde 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -41,6 +41,7 @@ config XTENSA select IRQ_DOMAIN select MODULES_USE_ELF_RELA select PERF_USE_VMALLOC + select SET_FS select VIRT_TO_BUS help Xtensa processors are 32-bit RISC machines designed by Tensilica diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index 94b28541165929..70073c802b48ed 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -8,6 +8,7 @@ #include +#ifdef CONFIG_SET_FS /* * Force the uaccess routines to be wired up for actual userspace access, * overriding any possible set_fs(KERNEL_DS) still lingering around. Undone @@ -25,6 +26,23 @@ static inline void force_uaccess_end(mm_segment_t oldfs) { set_fs(oldfs); } +#else /* CONFIG_SET_FS */ +typedef struct { + /* empty dummy */ +} mm_segment_t; + +#define uaccess_kernel() (false) +#define user_addr_max() (TASK_SIZE_MAX) + +static inline mm_segment_t force_uaccess_begin(void) +{ + return (mm_segment_t) { }; +} + +static inline void force_uaccess_end(mm_segment_t oldfs) +{ +} +#endif /* CONFIG_SET_FS */ /* * Architectures should provide two primitives (raw_copy_{to,from}_user()) From patchwork Mon Aug 17 07:32:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345708 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVQmg2dKcz9sPC for ; Mon, 17 Aug 2020 17:34:59 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=nPKsqCwn; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVQmf4wllzDqNL for ; Mon, 17 Aug 2020 17:34:58 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=casper.srs.infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=batv+1cabf852a0fb828109f5+6203+infradead.org+hch@casper.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=nPKsqCwn; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BVQjm4vk4zDqNB for ; Mon, 17 Aug 2020 17:32:28 +1000 (AEST) 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=chkBUohlSENVG7jzFIol9qd0YuUufR27opLGYVm+1Ug=; b=nPKsqCwnley2pS/jGgzaWIWqdq +H7a88VNXjG35LPNiZ70Kq+7+6Gu3tLxQga7o8tF/RFW8obhq2FJOJAyEb27ONJcpWauRW+6jPNZZ s2p1syRBxG+7Zznv0MvH0KZCg4uUaXzvWNUzIrxQoH1qGhjKwe9+K8EoC8VMyfYHj2C+Rf7YmyUjB 9cvFklBwOIFdee9QbYzjUx4FgKXyy5tI5cDIjL76f4STmRLqqZmkTKqKHi9k8VQ9XdmqFdtmBpO/1 gEuSuTWhDc+hCkkOLVFdlq+dEoEZbvtg6iVS1PKVj0Gp7LURgpjFVXy1eb9fYkzUOMLCF0hqjeRd+ mz7yZVjw==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd0-0000vz-Gj; Mon, 17 Aug 2020 07:32:22 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 05/11] test_bitmap: skip user bitmap tests for !CONFIG_SET_FS Date: Mon, 17 Aug 2020 09:32:06 +0200 Message-Id: <20200817073212.830069-6-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" We can't run the tests for userspace bitmap parsing if set_fs() doesn't exist. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- lib/test_bitmap.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c index df903c53952bb9..49b1d25fbaf546 100644 --- a/lib/test_bitmap.c +++ b/lib/test_bitmap.c @@ -365,6 +365,7 @@ static void __init __test_bitmap_parselist(int is_user) for (i = 0; i < ARRAY_SIZE(parselist_tests); i++) { #define ptest parselist_tests[i] +#ifdef CONFIG_SET_FS if (is_user) { mm_segment_t orig_fs = get_fs(); size_t len = strlen(ptest.in); @@ -375,7 +376,9 @@ static void __init __test_bitmap_parselist(int is_user) bmap, ptest.nbits); time = ktime_get() - time; set_fs(orig_fs); - } else { + } else +#endif /* CONFIG_SET_FS */ + { time = ktime_get(); err = bitmap_parselist(ptest.in, bmap, ptest.nbits); time = ktime_get() - time; @@ -454,6 +457,7 @@ static void __init __test_bitmap_parse(int is_user) for (i = 0; i < ARRAY_SIZE(parse_tests); i++) { struct test_bitmap_parselist test = parse_tests[i]; +#ifdef CONFIG_SET_FS if (is_user) { size_t len = strlen(test.in); mm_segment_t orig_fs = get_fs(); @@ -464,7 +468,9 @@ static void __init __test_bitmap_parse(int is_user) bmap, test.nbits); time = ktime_get() - time; set_fs(orig_fs); - } else { + } else +#endif /* CONFIG_SET_FS */ + { size_t len = test.flags & NO_LEN ? UINT_MAX : strlen(test.in); time = ktime_get(); From patchwork Mon Aug 17 07:32:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345714 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVQv920Dsz9sTK for ; Mon, 17 Aug 2020 17:40:37 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=mDbBIzqp; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVQv76nXKzDqCG for ; Mon, 17 Aug 2020 17:40:35 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=casper.srs.infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=batv+1cabf852a0fb828109f5+6203+infradead.org+hch@casper.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=mDbBIzqp; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BVQjp277ZzDqND for ; Mon, 17 Aug 2020 17:32:30 +1000 (AEST) 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=Y/gPSrkcO0WTBRy6i45H6VgYWvtoV6CDlRazRsDykmI=; b=mDbBIzqpRFZmPKJME9zJ5B6R80 fAir7UfNE2GI1NIAug65/QMmCPxR8FLQLYWm2LtvqDRk0UOz/OsfX6aM6ILoUjPONfhm/Owd4xyEO XHyPQZmphYMb2tzsOd5O015Fm4+he404d4ul0XJHyfUGOUYHKSq1nrrhsgbLQeBcJkMgFbO++HYv7 nIIgiAWsUb5Z2doPvKSiUNRZY5InCEefBFmun51u9FHVm/KL1BmdUv4X04LpmI6xZUwIFs66tKBpj TQNxZWavJtci0faEGIVLJOePM6jbSorgyIS/q9vkKYsPq5NyRZf6FqV8tHuF/oPLFGvbW2Vcl4OJo QnegHBKQ==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd1-0000wH-QO; Mon, 17 Aug 2020 07:32:24 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 06/11] lkdtm: disable set_fs-based tests for !CONFIG_SET_FS Date: Mon, 17 Aug 2020 09:32:07 +0200 Message-Id: <20200817073212.830069-7-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Once we can't manipulate the address limit, we also can't test what happens when the manipulation is abused. Signed-off-by: Christoph Hellwig --- drivers/misc/lkdtm/bugs.c | 2 ++ drivers/misc/lkdtm/core.c | 4 ++++ drivers/misc/lkdtm/usercopy.c | 2 ++ 3 files changed, 8 insertions(+) diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c index 4dfbfd51bdf774..66f1800b1cb82d 100644 --- a/drivers/misc/lkdtm/bugs.c +++ b/drivers/misc/lkdtm/bugs.c @@ -312,6 +312,7 @@ void lkdtm_CORRUPT_LIST_DEL(void) pr_err("list_del() corruption not detected!\n"); } +#ifdef CONFIG_SET_FS /* Test if unbalanced set_fs(KERNEL_DS)/set_fs(USER_DS) check exists. */ void lkdtm_CORRUPT_USER_DS(void) { @@ -321,6 +322,7 @@ void lkdtm_CORRUPT_USER_DS(void) /* Make sure we do not keep running with a KERNEL_DS! */ force_sig(SIGKILL); } +#endif /* Test that VMAP_STACK is actually allocating with a leading guard page */ void lkdtm_STACK_GUARD_PAGE_LEADING(void) diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c index a5e344df916632..aae08b33a7ee2a 100644 --- a/drivers/misc/lkdtm/core.c +++ b/drivers/misc/lkdtm/core.c @@ -112,7 +112,9 @@ static const struct crashtype crashtypes[] = { CRASHTYPE(CORRUPT_STACK_STRONG), CRASHTYPE(CORRUPT_LIST_ADD), CRASHTYPE(CORRUPT_LIST_DEL), +#ifdef CONFIG_SET_FS CRASHTYPE(CORRUPT_USER_DS), +#endif CRASHTYPE(STACK_GUARD_PAGE_LEADING), CRASHTYPE(STACK_GUARD_PAGE_TRAILING), CRASHTYPE(UNSET_SMEP), @@ -172,7 +174,9 @@ static const struct crashtype crashtypes[] = { CRASHTYPE(USERCOPY_STACK_FRAME_FROM), CRASHTYPE(USERCOPY_STACK_BEYOND), CRASHTYPE(USERCOPY_KERNEL), +#ifdef CONFIG_SET_FS CRASHTYPE(USERCOPY_KERNEL_DS), +#endif CRASHTYPE(STACKLEAK_ERASING), CRASHTYPE(CFI_FORWARD_PROTO), #ifdef CONFIG_X86_32 diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c index b833367a45d053..4b632fe79ab6bb 100644 --- a/drivers/misc/lkdtm/usercopy.c +++ b/drivers/misc/lkdtm/usercopy.c @@ -325,6 +325,7 @@ void lkdtm_USERCOPY_KERNEL(void) vm_munmap(user_addr, PAGE_SIZE); } +#ifdef CONFIG_SET_FS void lkdtm_USERCOPY_KERNEL_DS(void) { char __user *user_ptr = @@ -339,6 +340,7 @@ void lkdtm_USERCOPY_KERNEL_DS(void) pr_err("copy_to_user() to noncanonical address succeeded!?\n"); set_fs(old_fs); } +#endif void __init lkdtm_usercopy_init(void) { From patchwork Mon Aug 17 07:32:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345727 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVR1t2tfMz9sTQ for ; Mon, 17 Aug 2020 17:46:26 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; 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Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd3-0000wS-2Y; Mon, 17 Aug 2020 07:32:25 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 07/11] x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32, 64}_types.h Date: Mon, 17 Aug 2020 09:32:08 +0200 Message-Id: <20200817073212.830069-8-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" At least for 64-bit this moves them closer to some of the defines they are based on, and it prepares for using the TASK_SIZE_MAX definition from assembly. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- arch/x86/include/asm/page_32_types.h | 11 +++++++ arch/x86/include/asm/page_64_types.h | 38 +++++++++++++++++++++ arch/x86/include/asm/processor.h | 49 ---------------------------- 3 files changed, 49 insertions(+), 49 deletions(-) diff --git a/arch/x86/include/asm/page_32_types.h b/arch/x86/include/asm/page_32_types.h index 565ad755c785e2..26236925fb2c36 100644 --- a/arch/x86/include/asm/page_32_types.h +++ b/arch/x86/include/asm/page_32_types.h @@ -41,6 +41,17 @@ #define __VIRTUAL_MASK_SHIFT 32 #endif /* CONFIG_X86_PAE */ +/* + * User space process size: 3GB (default). + */ +#define IA32_PAGE_OFFSET PAGE_OFFSET +#define TASK_SIZE PAGE_OFFSET +#define TASK_SIZE_LOW TASK_SIZE +#define TASK_SIZE_MAX TASK_SIZE +#define DEFAULT_MAP_WINDOW TASK_SIZE +#define STACK_TOP TASK_SIZE +#define STACK_TOP_MAX STACK_TOP + /* * Kernel image size is limited to 512 MB (see in arch/x86/kernel/head_32.S) */ diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index 288b065955b729..996595c9897e0a 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -58,6 +58,44 @@ #define __VIRTUAL_MASK_SHIFT 47 #endif +/* + * User space process size. This is the first address outside the user range. + * There are a few constraints that determine this: + * + * On Intel CPUs, if a SYSCALL instruction is at the highest canonical + * address, then that syscall will enter the kernel with a + * non-canonical return address, and SYSRET will explode dangerously. + * We avoid this particular problem by preventing anything executable + * from being mapped at the maximum canonical address. + * + * On AMD CPUs in the Ryzen family, there's a nasty bug in which the + * CPUs malfunction if they execute code from the highest canonical page. + * They'll speculate right off the end of the canonical space, and + * bad things happen. This is worked around in the same way as the + * Intel problem. + * + * With page table isolation enabled, we map the LDT in ... [stay tuned] + */ +#define TASK_SIZE_MAX ((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE) + +#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) + +/* This decides where the kernel will search for a free chunk of vm + * space during mmap's. + */ +#define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \ + 0xc0000000 : 0xFFFFe000) + +#define TASK_SIZE_LOW (test_thread_flag(TIF_ADDR32) ? \ + IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW) +#define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \ + IA32_PAGE_OFFSET : TASK_SIZE_MAX) +#define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \ + IA32_PAGE_OFFSET : TASK_SIZE_MAX) + +#define STACK_TOP TASK_SIZE_LOW +#define STACK_TOP_MAX TASK_SIZE_MAX + /* * Maximum kernel image size is limited to 1 GiB, due to the fixmap living * in the next 1 GiB (see level2_kernel_pgt in arch/x86/kernel/head_64.S). diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 97143d87994c24..1618eeb08361a9 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -782,17 +782,6 @@ static inline void spin_lock_prefetch(const void *x) }) #ifdef CONFIG_X86_32 -/* - * User space process size: 3GB (default). - */ -#define IA32_PAGE_OFFSET PAGE_OFFSET -#define TASK_SIZE PAGE_OFFSET -#define TASK_SIZE_LOW TASK_SIZE -#define TASK_SIZE_MAX TASK_SIZE -#define DEFAULT_MAP_WINDOW TASK_SIZE -#define STACK_TOP TASK_SIZE -#define STACK_TOP_MAX STACK_TOP - #define INIT_THREAD { \ .sp0 = TOP_OF_INIT_STACK, \ .sysenter_cs = __KERNEL_CS, \ @@ -802,44 +791,6 @@ static inline void spin_lock_prefetch(const void *x) #define KSTK_ESP(task) (task_pt_regs(task)->sp) #else -/* - * User space process size. This is the first address outside the user range. - * There are a few constraints that determine this: - * - * On Intel CPUs, if a SYSCALL instruction is at the highest canonical - * address, then that syscall will enter the kernel with a - * non-canonical return address, and SYSRET will explode dangerously. - * We avoid this particular problem by preventing anything executable - * from being mapped at the maximum canonical address. - * - * On AMD CPUs in the Ryzen family, there's a nasty bug in which the - * CPUs malfunction if they execute code from the highest canonical page. - * They'll speculate right off the end of the canonical space, and - * bad things happen. This is worked around in the same way as the - * Intel problem. - * - * With page table isolation enabled, we map the LDT in ... [stay tuned] - */ -#define TASK_SIZE_MAX ((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE) - -#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) - -/* This decides where the kernel will search for a free chunk of vm - * space during mmap's. - */ -#define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \ - 0xc0000000 : 0xFFFFe000) - -#define TASK_SIZE_LOW (test_thread_flag(TIF_ADDR32) ? \ - IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW) -#define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \ - IA32_PAGE_OFFSET : TASK_SIZE_MAX) -#define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \ - IA32_PAGE_OFFSET : TASK_SIZE_MAX) - -#define STACK_TOP TASK_SIZE_LOW -#define STACK_TOP_MAX TASK_SIZE_MAX - #define INIT_THREAD { \ .addr_limit = KERNEL_DS, \ } From patchwork Mon Aug 17 07:32:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345728 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVR6B2Nxzz9sTM for ; Mon, 17 Aug 2020 17:50:10 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=DRbSf1xd; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVR696pwPzDqN8 for ; Mon, 17 Aug 2020 17:50:09 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=casper.srs.infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=batv+1cabf852a0fb828109f5+6203+infradead.org+hch@casper.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=DRbSf1xd; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BVQjs0t11zDqMG for ; Mon, 17 Aug 2020 17:32:32 +1000 (AEST) 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=kbVpg/Cl7hMfUpOgrf+/Vgol2i5kqu+MYLE479vmK28=; b=DRbSf1xdtM0Veg0yrNRpLZXRjf q1WKVkrp3BJUpkB5kIhmQHz8q3FUV4DkBN8Bhd9c8EQ39b7lazN0kSQNsXRZ7fek8lKmaiw9R/s6u +BJfkllHYNyp7/lAJsZ1E0sSklSUEBXdy+uK0bGT9BfOWwtDZsBG0qXjw8ibhyq9HyigEXAmuOwWv LRycTnwzhscQ2ZHZOiZ3r9A1VxorQ+ObkBQ7Ri+QNRIJ9OqXobvG6vDtibaUpmBthcfYuZpeQ0J4h lqELAh9ElaLekMU1L72SC6fsd3gT40ZLwJxZb5HRzrUr3lplbGivjU5XL+NKeEH/nAoygyPCdvk7s WxdH8Geg==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd4-0000wg-E8; Mon, 17 Aug 2020 07:32:27 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 08/11] x86: make TASK_SIZE_MAX usable from assembly code Date: Mon, 17 Aug 2020 09:32:09 +0200 Message-Id: <20200817073212.830069-9-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" For 64-bit the only hing missing was a strategic _AC, and for 32-bit we need to use __PAGE_OFFSET instead of PAGE_OFFSET in the TASK_SIZE definition to escape the explicit unsigned long cast. This just works because __PAGE_OFFSET is defined using _AC itself and thus never needs the cast anyway. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- arch/x86/include/asm/page_32_types.h | 4 ++-- arch/x86/include/asm/page_64_types.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/page_32_types.h b/arch/x86/include/asm/page_32_types.h index 26236925fb2c36..f462895a33e452 100644 --- a/arch/x86/include/asm/page_32_types.h +++ b/arch/x86/include/asm/page_32_types.h @@ -44,8 +44,8 @@ /* * User space process size: 3GB (default). */ -#define IA32_PAGE_OFFSET PAGE_OFFSET -#define TASK_SIZE PAGE_OFFSET +#define IA32_PAGE_OFFSET __PAGE_OFFSET +#define TASK_SIZE __PAGE_OFFSET #define TASK_SIZE_LOW TASK_SIZE #define TASK_SIZE_MAX TASK_SIZE #define DEFAULT_MAP_WINDOW TASK_SIZE diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index 996595c9897e0a..838515daf87b36 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -76,7 +76,7 @@ * * With page table isolation enabled, we map the LDT in ... [stay tuned] */ -#define TASK_SIZE_MAX ((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE) +#define TASK_SIZE_MAX ((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE) #define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) From patchwork Mon Aug 17 07:32:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345732 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVR9r1THSz9sPC for ; Mon, 17 Aug 2020 17:53:20 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=U/VA45Pz; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVR9r0xPczDqNT for ; Mon, 17 Aug 2020 17:53:20 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=casper.srs.infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=batv+1cabf852a0fb828109f5+6203+infradead.org+hch@casper.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=U/VA45Pz; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BVQjt6b5wzDqMG for ; Mon, 17 Aug 2020 17:32:34 +1000 (AEST) 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=HNR/cS/AJ6roKIxtNpJ+9vihs4XEcXh0pr1qAX7tvRg=; b=U/VA45PzCKloPeRRX1D3kixSvb SrOkYb3Lj74rEfUIOTSyy1NLY/ZwVpO1eQ1Mcbq910IvO4N6cAXJMZaquAXzVKSnsCBXcWwhBDPBA pQalmndyQjFxSkrWq7jQJ0UbsumNyIO/wI4E5fmrV0mUjipFnaMYhp//ThYFtvXiV5PGPcq8Zp/FW JbNryc4oqpqojXIPD5rKpAHaVXHE+xUEqSTqWgf+RKXdozoR7xULh+FIHiz9o+PTyGEIF46GzecNb 2SQoLy0dQeblZr2mde4D4I0gIC+SwTMrEE/Lth1b6xkLFx/d6pWOCdqWCf91e7pReAOZoXdnpHI/e BBpJ39fw==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd6-0000wv-7e; Mon, 17 Aug 2020 07:32:28 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 09/11] x86: remove address space overrides using set_fs() Date: Mon, 17 Aug 2020 09:32:10 +0200 Message-Id: <20200817073212.830069-10-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Stop providing the possibility to override the address space using set_fs() now that there is no need for that any more. To properly handle the TASK_SIZE_MAX checking for 4 vs 5-level page tables on x86 a new alternative is introduced, which just like the one in entry_64.S has to use the hardcoded virtual address bits to escape the fact that TASK_SIZE_MAX isn't actually a constant when 5-level page tables are enabled. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- arch/x86/Kconfig | 1 - arch/x86/ia32/ia32_aout.c | 1 - arch/x86/include/asm/processor.h | 11 +---------- arch/x86/include/asm/thread_info.h | 2 -- arch/x86/include/asm/uaccess.h | 26 +------------------------- arch/x86/kernel/asm-offsets.c | 3 --- arch/x86/lib/getuser.S | 28 ++++++++++++++++++---------- arch/x86/lib/putuser.S | 21 ++++++++++++--------- 8 files changed, 32 insertions(+), 61 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index f85c13355732fe..7101ac64bb209d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -237,7 +237,6 @@ config X86 select HAVE_ARCH_KCSAN if X86_64 select X86_FEATURE_NAMES if PROC_FS select PROC_PID_ARCH_STATUS if PROC_FS - select SET_FS imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI config INSTRUCTION_DECODER diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c index ca8a657edf5977..a09fc37ead9d47 100644 --- a/arch/x86/ia32/ia32_aout.c +++ b/arch/x86/ia32/ia32_aout.c @@ -239,7 +239,6 @@ static int load_aout_binary(struct linux_binprm *bprm) (regs)->ss = __USER32_DS; regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0; - set_fs(USER_DS); return 0; } diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 1618eeb08361a9..189573d95c3af6 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -482,10 +482,6 @@ extern unsigned int fpu_user_xstate_size; struct perf_event; -typedef struct { - unsigned long seg; -} mm_segment_t; - struct thread_struct { /* Cached TLS descriptors: */ struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES]; @@ -538,8 +534,6 @@ struct thread_struct { */ unsigned long iopl_emul; - mm_segment_t addr_limit; - unsigned int sig_on_uaccess_err:1; /* Floating point and extended processor state */ @@ -785,15 +779,12 @@ static inline void spin_lock_prefetch(const void *x) #define INIT_THREAD { \ .sp0 = TOP_OF_INIT_STACK, \ .sysenter_cs = __KERNEL_CS, \ - .addr_limit = KERNEL_DS, \ } #define KSTK_ESP(task) (task_pt_regs(task)->sp) #else -#define INIT_THREAD { \ - .addr_limit = KERNEL_DS, \ -} +#define INIT_THREAD { } extern unsigned long KSTK_ESP(struct task_struct *task); diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 267701ae3d86dd..44733a4bfc4294 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -102,7 +102,6 @@ struct thread_info { #define TIF_SYSCALL_TRACEPOINT 28 /* syscall tracepoint instrumentation */ #define TIF_ADDR32 29 /* 32-bit address space on 64 bits */ #define TIF_X32 30 /* 32-bit native x86-64 binary */ -#define TIF_FSCHECK 31 /* Check FS is USER_DS on return */ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) @@ -131,7 +130,6 @@ struct thread_info { #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) #define _TIF_ADDR32 (1 << TIF_ADDR32) #define _TIF_X32 (1 << TIF_X32) -#define _TIF_FSCHECK (1 << TIF_FSCHECK) /* flags to check in __switch_to() */ #define _TIF_WORK_CTXSW_BASE \ diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index ecefaffd15d4c8..a4ceda0510ea87 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -12,30 +12,6 @@ #include #include -/* - * The fs value determines whether argument validity checking should be - * performed or not. If get_fs() == USER_DS, checking is performed, with - * get_fs() == KERNEL_DS, checking is bypassed. - * - * For historical reasons, these macros are grossly misnamed. - */ - -#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) - -#define KERNEL_DS MAKE_MM_SEG(-1UL) -#define USER_DS MAKE_MM_SEG(TASK_SIZE_MAX) - -#define get_fs() (current->thread.addr_limit) -static inline void set_fs(mm_segment_t fs) -{ - current->thread.addr_limit = fs; - /* On user-mode return, check fs is correct */ - set_thread_flag(TIF_FSCHECK); -} - -#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg) -#define user_addr_max() (current->thread.addr_limit.seg) - /* * Test whether a block of memory is a valid user space address. * Returns 0 if the range is valid, nonzero otherwise. @@ -93,7 +69,7 @@ static inline bool pagefault_disabled(void); #define access_ok(addr, size) \ ({ \ WARN_ON_IN_IRQ(); \ - likely(!__range_not_ok(addr, size, user_addr_max())); \ + likely(!__range_not_ok(addr, size, TASK_SIZE_MAX)); \ }) /* diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c index 3ca07ad552ae0c..70b7154f4bdd62 100644 --- a/arch/x86/kernel/asm-offsets.c +++ b/arch/x86/kernel/asm-offsets.c @@ -37,9 +37,6 @@ static void __used common(void) OFFSET(TASK_stack_canary, task_struct, stack_canary); #endif - BLANK(); - OFFSET(TASK_addr_limit, task_struct, thread.addr_limit); - BLANK(); OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx); diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S index c8a85b512796e1..ccc9808c66420a 100644 --- a/arch/x86/lib/getuser.S +++ b/arch/x86/lib/getuser.S @@ -35,10 +35,18 @@ #include #include +#ifdef CONFIG_X86_5LEVEL +#define LOAD_TASK_SIZE_MAX \ + ALTERNATIVE "mov $((1 << 47) - 4096),%rdx", \ + "mov $((1 << 56) - 4096),%rdx", X86_FEATURE_LA57 +#else +#define LOAD_TASK_SIZE_MAX mov $TASK_SIZE_MAX,%_ASM_DX +#endif + .text SYM_FUNC_START(__get_user_1) - mov PER_CPU_VAR(current_task), %_ASM_DX - cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX + LOAD_TASK_SIZE_MAX + cmp %_ASM_DX,%_ASM_AX jae bad_get_user sbb %_ASM_DX, %_ASM_DX /* array_index_mask_nospec() */ and %_ASM_DX, %_ASM_AX @@ -53,8 +61,8 @@ EXPORT_SYMBOL(__get_user_1) SYM_FUNC_START(__get_user_2) add $1,%_ASM_AX jc bad_get_user - mov PER_CPU_VAR(current_task), %_ASM_DX - cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX + LOAD_TASK_SIZE_MAX + cmp %_ASM_DX,%_ASM_AX jae bad_get_user sbb %_ASM_DX, %_ASM_DX /* array_index_mask_nospec() */ and %_ASM_DX, %_ASM_AX @@ -69,8 +77,8 @@ EXPORT_SYMBOL(__get_user_2) SYM_FUNC_START(__get_user_4) add $3,%_ASM_AX jc bad_get_user - mov PER_CPU_VAR(current_task), %_ASM_DX - cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX + LOAD_TASK_SIZE_MAX + cmp %_ASM_DX,%_ASM_AX jae bad_get_user sbb %_ASM_DX, %_ASM_DX /* array_index_mask_nospec() */ and %_ASM_DX, %_ASM_AX @@ -86,8 +94,8 @@ SYM_FUNC_START(__get_user_8) #ifdef CONFIG_X86_64 add $7,%_ASM_AX jc bad_get_user - mov PER_CPU_VAR(current_task), %_ASM_DX - cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX + LOAD_TASK_SIZE_MAX + cmp %_ASM_DX,%_ASM_AX jae bad_get_user sbb %_ASM_DX, %_ASM_DX /* array_index_mask_nospec() */ and %_ASM_DX, %_ASM_AX @@ -99,8 +107,8 @@ SYM_FUNC_START(__get_user_8) #else add $7,%_ASM_AX jc bad_get_user_8 - mov PER_CPU_VAR(current_task), %_ASM_DX - cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX + LOAD_TASK_SIZE_MAX + cmp %_ASM_DX,%_ASM_AX jae bad_get_user_8 sbb %_ASM_DX, %_ASM_DX /* array_index_mask_nospec() */ and %_ASM_DX, %_ASM_AX diff --git a/arch/x86/lib/putuser.S b/arch/x86/lib/putuser.S index 7c7c92db8497af..f5a56394985875 100644 --- a/arch/x86/lib/putuser.S +++ b/arch/x86/lib/putuser.S @@ -31,12 +31,18 @@ * as they get called from within inline assembly. */ -#define ENTER mov PER_CPU_VAR(current_task), %_ASM_BX +#ifdef CONFIG_X86_5LEVEL +#define LOAD_TASK_SIZE_MAX \ + ALTERNATIVE "mov $((1 << 47) - 4096),%rbx", \ + "mov $((1 << 56) - 4096),%rbx", X86_FEATURE_LA57 +#else +#define LOAD_TASK_SIZE_MAX mov $TASK_SIZE_MAX,%_ASM_BX +#endif .text SYM_FUNC_START(__put_user_1) - ENTER - cmp TASK_addr_limit(%_ASM_BX),%_ASM_CX + LOAD_TASK_SIZE_MAX + cmp %_ASM_BX,%_ASM_CX jae .Lbad_put_user ASM_STAC 1: movb %al,(%_ASM_CX) @@ -47,8 +53,7 @@ SYM_FUNC_END(__put_user_1) EXPORT_SYMBOL(__put_user_1) SYM_FUNC_START(__put_user_2) - ENTER - mov TASK_addr_limit(%_ASM_BX),%_ASM_BX + LOAD_TASK_SIZE_MAX sub $1,%_ASM_BX cmp %_ASM_BX,%_ASM_CX jae .Lbad_put_user @@ -61,8 +66,7 @@ SYM_FUNC_END(__put_user_2) EXPORT_SYMBOL(__put_user_2) SYM_FUNC_START(__put_user_4) - ENTER - mov TASK_addr_limit(%_ASM_BX),%_ASM_BX + LOAD_TASK_SIZE_MAX sub $3,%_ASM_BX cmp %_ASM_BX,%_ASM_CX jae .Lbad_put_user @@ -75,8 +79,7 @@ SYM_FUNC_END(__put_user_4) EXPORT_SYMBOL(__put_user_4) SYM_FUNC_START(__put_user_8) - ENTER - mov TASK_addr_limit(%_ASM_BX),%_ASM_BX + LOAD_TASK_SIZE_MAX sub $7,%_ASM_BX cmp %_ASM_BX,%_ASM_CX jae .Lbad_put_user From patchwork Mon Aug 17 07:32:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345733 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVRCs3Qr3z9sPC for ; Mon, 17 Aug 2020 17:55:05 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=mK1/oXp6; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVRCs0PcgzDqQX for ; 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Mon, 17 Aug 2020 17:32:36 +1000 (AEST) 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=3qEOF4AeMzDrBPiTnGe1Fi7T4ulUxh9tT2b5Llhhj24=; b=mK1/oXp62aR0yay7hI5rxF1rAO oIsweDRzAybAXvXwihafnDeOYhrE2n+0bZlTynkTLCeN2Dft2OWptTFcZ0c+Ljmzou4BBptsQZ+cE 0WcSunosxHVcotlNa/rI3b318DLQXHBoYZZegd9x5Yis9biXRTIjkMLxPL3Usu9AkBvWYJ3qmMQf1 l6wqXqzOVXQI/CO1e536dwgXJwAxJPt8DWi26u63Db+xcZ7fBk6a4uIvosgZsLEb9gJZhTvzW+Ta5 YxOkXrxmW78qeAsfMYFzC1ir41mo1Ahv1Nsz4QILF/04RjFQMvKx+/88wZzYfZLpGewiWy9mnrHqC +/UpGE0w==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd8-0000x5-1X; Mon, 17 Aug 2020 07:32:30 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 10/11] powerpc: use non-set_fs based maccess routines Date: Mon, 17 Aug 2020 09:32:11 +0200 Message-Id: <20200817073212.830069-11-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Provide __get_kernel_nofault and __put_kernel_nofault routines to implement the maccess routines without messing with set_fs and without opening up access to user space. Signed-off-by: Christoph Hellwig --- arch/powerpc/include/asm/uaccess.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index 00699903f1efca..a31de40ac00b62 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -623,4 +623,20 @@ do { \ __put_user_goto(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), e);\ } while (0) +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + int __kr_err; \ + \ + __get_user_size(*((type *)(dst)), (__force type __user *)(src), \ + sizeof(type), __kr_err); \ + if (unlikely(__kr_err)) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ + __put_user_size_goto(*((type *)(src)), \ + (__force type __user *)(dst), sizeof(type), err_label) + #endif /* _ARCH_POWERPC_UACCESS_H */ From patchwork Mon Aug 17 07:32:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1345734 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4BVRGf5QmJz9sPC for ; Mon, 17 Aug 2020 17:57:30 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=LsTfhQy7; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BVRGf5157zDqNW for ; Mon, 17 Aug 2020 17:57:30 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=casper.srs.infradead.org (client-ip=2001:8b0:10b:1236::1; helo=casper.infradead.org; envelope-from=batv+1cabf852a0fb828109f5+6203+infradead.org+hch@casper.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=casper.20170209 header.b=LsTfhQy7; dkim-atps=neutral Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BVQjx71yMzDqMG for ; Mon, 17 Aug 2020 17:32:37 +1000 (AEST) 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=cV7tx6a0jVlSivNugnCBOaJfYdBiZa/z8SEDIVSzu0k=; b=LsTfhQy76tuX5jVGOlCWM3WeJY 4RUzlv4TX/AVhepypQt53XWJYMI9pm2HnoN1mYxvWCxMu1NJ9/IwnEPu2qTdjOBNHJLId5FBsctos r+dV4UYicRiu4M8PoprFcKq3U5eaDOIDdqH+9rUHq7Ei6E0bGL7rCvKrcHS93omoJPZP2PCRrloW4 F9hgi+dtPUvv3LLZ9vsTJReCAud09XRNvrNwmXck4DOhxIDd1yvr1CHK+R1BXxmHR5NiHGvPhQNdj hIw8ha2y77arJf/Kj3NtVzMdOEGcEFiJFA7iOWpE1YwRy4ARQMaPO89O1/nvwleF/iGWRXScVni48 7FnCbjlQ==; Received: from [2001:4bb8:188:3918:4550:cdf7:3d45:afb9] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7Zd9-0000xE-82; Mon, 17 Aug 2020 07:32:32 +0000 From: Christoph Hellwig To: Al Viro , Michael Ellerman , x86@kernel.org Subject: [PATCH 11/11] powerpc: remove address space overrides using set_fs() Date: Mon, 17 Aug 2020 09:32:12 +0200 Message-Id: <20200817073212.830069-12-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817073212.830069-1-hch@lst.de> References: <20200817073212.830069-1-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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Kees Cook , linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Stop providing the possibility to override the address space using set_fs() now that there is no need for that any more. Signed-off-by: Christoph Hellwig --- arch/powerpc/Kconfig | 1 - arch/powerpc/include/asm/processor.h | 7 --- arch/powerpc/include/asm/thread_info.h | 5 +-- arch/powerpc/include/asm/uaccess.h | 62 ++++++++------------------ arch/powerpc/kernel/signal.c | 3 -- arch/powerpc/lib/sstep.c | 6 +-- 6 files changed, 22 insertions(+), 62 deletions(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3f09d6fdf89405..1f48bbfb3ce99d 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -249,7 +249,6 @@ config PPC select PCI_SYSCALL if PCI select PPC_DAWR if PPC64 select RTC_LIB - select SET_FS select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index ed0d633ab5aa42..f01e4d650c520a 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -83,10 +83,6 @@ struct task_struct; void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp); void release_thread(struct task_struct *); -typedef struct { - unsigned long seg; -} mm_segment_t; - #define TS_FPR(i) fp_state.fpr[i][TS_FPROFFSET] #define TS_CKFPR(i) ckfp_state.fpr[i][TS_FPROFFSET] @@ -148,7 +144,6 @@ struct thread_struct { unsigned long ksp_vsid; #endif struct pt_regs *regs; /* Pointer to saved register state */ - mm_segment_t addr_limit; /* for get_fs() validation */ #ifdef CONFIG_BOOKE /* BookE base exception scratch space; align on cacheline */ unsigned long normsave[8] ____cacheline_aligned; @@ -295,7 +290,6 @@ struct thread_struct { #define INIT_THREAD { \ .ksp = INIT_SP, \ .ksp_limit = INIT_SP_LIMIT, \ - .addr_limit = KERNEL_DS, \ .pgdir = swapper_pg_dir, \ .fpexc_mode = MSR_FE0 | MSR_FE1, \ SPEFSCR_INIT \ @@ -303,7 +297,6 @@ struct thread_struct { #else #define INIT_THREAD { \ .ksp = INIT_SP, \ - .addr_limit = KERNEL_DS, \ .fpexc_mode = 0, \ } #endif diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index ca6c9702570494..46a210b03d2b80 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -90,7 +90,6 @@ void arch_setup_new_exec(void); #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_SIGPENDING 1 /* signal pending */ #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ -#define TIF_FSCHECK 3 /* Check FS is USER_DS on return */ #define TIF_SYSCALL_EMU 4 /* syscall emulation active */ #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */ #define TIF_PATCH_PENDING 6 /* pending live patching update */ @@ -130,7 +129,6 @@ void arch_setup_new_exec(void); #define _TIF_SYSCALL_TRACEPOINT (1< #include -/* - * The fs value determines whether argument validity checking should be - * performed or not. If get_fs() == USER_DS, checking is performed, with - * get_fs() == KERNEL_DS, checking is bypassed. - * - * For historical reasons, these macros are grossly misnamed. - * - * The fs/ds values are now the highest legal address in the "segment". - * This simplifies the checking in the routines below. - */ - -#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) - -#define KERNEL_DS MAKE_MM_SEG(~0UL) #ifdef __powerpc64__ /* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */ -#define USER_DS MAKE_MM_SEG(TASK_SIZE_USER64 - 1) -#else -#define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) -#endif - -#define get_fs() (current->thread.addr_limit) +#define TASK_SIZE_MAX TASK_SIZE_USER64 -static inline void set_fs(mm_segment_t fs) +static inline bool __access_ok(unsigned long addr, unsigned long size) { - current->thread.addr_limit = fs; - /* On user-mode return check addr_limit (fs) is correct */ - set_thread_flag(TIF_FSCHECK); + if (addr >= TASK_SIZE_MAX) + return false; + /* + * This check is sufficient because there is a large enough gap between + * user addresses and the kernel addresses. + */ + return size <= TASK_SIZE_MAX; } - -#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg) -#define user_addr_max() (get_fs().seg) - -#ifdef __powerpc64__ -/* - * This check is sufficient because there is a large enough - * gap between user addresses and the kernel addresses - */ -#define __access_ok(addr, size, segment) \ - (((addr) <= (segment).seg) && ((size) <= (segment).seg)) - #else +#define TASK_SIZE_MAX TASK_SIZE -static inline int __access_ok(unsigned long addr, unsigned long size, - mm_segment_t seg) +static inline bool __access_ok(unsigned long addr, unsigned long size) { - if (addr > seg.seg) - return 0; - return (size == 0 || size - 1 <= seg.seg - addr); + if (addr >= TASK_SIZE_MAX) + return false; + if (size == 0) + return false; + return size <= TASK_SIZE_MAX - addr; } - -#endif +#endif /* __powerpc64__ */ #define access_ok(addr, size) \ (__chk_user_ptr(addr), \ - __access_ok((__force unsigned long)(addr), (size), get_fs())) + __access_ok((unsigned long)(addr), (size))) /* * These are the main single-value transfer routines. They automatically diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index d15a98c758b8b4..df547d8e31e49c 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -312,9 +312,6 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) { user_exit(); - /* Check valid addr_limit, TIF check is done there */ - addr_limit_user_check(); - if (thread_info_flags & _TIF_UPROBE) uprobe_notify_resume(regs); diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index caee8cc77e1954..8342188ea1acd0 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -108,11 +108,11 @@ static nokprobe_inline long address_ok(struct pt_regs *regs, { if (!user_mode(regs)) return 1; - if (__access_ok(ea, nb, USER_DS)) + if (__access_ok(ea, nb)) return 1; - if (__access_ok(ea, 1, USER_DS)) + if (__access_ok(ea, 1)) /* Access overlaps the end of the user region */ - regs->dar = USER_DS.seg; + regs->dar = TASK_SIZE_MAX - 1; else regs->dar = ea; return 0;