From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67B65C433FE for ; Tue, 19 Apr 2022 18:22:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240906AbiDSSZN (ORCPT ); Tue, 19 Apr 2022 14:25:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357185AbiDSSWw (ORCPT ); Tue, 19 Apr 2022 14:22:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50F9A427EC; Tue, 19 Apr 2022 11:15:26 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B907960FEB; Tue, 19 Apr 2022 18:15:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B72EC385A5; Tue, 19 Apr 2022 18:15:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1650392125; bh=P4wHU4paOkXJSzIawgcr2zWj4eVddDDxzhzoHnGO/ik=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=scmqm6bj4czQwK8Rb3E9D09OQG8peX7g7+7SYFKgmaLHQkx0pHLEids4EjV/BDYpC wmFq8a7RyRtIJAMXlPCqmMqkZS4tmE0H5W+d5cKGA3ldUFI9a1Yo2M5sC1/69xRMzx MjLRa1x9w715gWDxJ+ZxWmnDvfprJHKnpHBqitAcnw+uED3dTobQouTZRfIdQNNyJ7 w1fZ1HAHfOGRmocCvUPqcF6uAtcpZPQm6q6WhzlTVMQ91ivIfyi2r+ccNQZqnyeeJv yxMOfp1fcMe5K47OaetzJYfTpCGX4spYHMpH87EHufWLPHgNbj5TmVnJli+BINE5MZ ifNBEpCRIpVqg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mikulas Patocka , Andreas Schwab , Matthew Wilcox , Christoph Hellwig , Linus Torvalds , Sasha Levin , tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, viro@zeniv.linux.org.uk, arnd@arndb.de, akpm@linux-foundation.org, davem@davemloft.net, linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 14/14] stat: fix inconsistency between struct stat and struct compat_stat Date: Tue, 19 Apr 2022 14:14:43 -0400 Message-Id: <20220419181444.485959-14-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220419181444.485959-1-sashal@kernel.org> References: <20220419181444.485959-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Mikulas Patocka [ Upstream commit 932aba1e169090357a77af18850a10c256b50819 ] struct stat (defined in arch/x86/include/uapi/asm/stat.h) has 32-bit st_dev and st_rdev; struct compat_stat (defined in arch/x86/include/asm/compat.h) has 16-bit st_dev and st_rdev followed by a 16-bit padding. This patch fixes struct compat_stat to match struct stat. [ Historical note: the old x86 'struct stat' did have that 16-bit field that the compat layer had kept around, but it was changes back in 2003 by "struct stat - support larger dev_t": https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/?id=e95b2065677fe32512a597a79db94b77b90c968d and back in those days, the x86_64 port was still new, and separate from the i386 code, and had already picked up the old version with a 16-bit st_dev field ] Note that we can't change compat_dev_t because it is used by compat_loop_info. Also, if the st_dev and st_rdev values are 32-bit, we don't have to use old_valid_dev to test if the value fits into them. This fixes -EOVERFLOW on filesystems that are on NVMe because NVMe uses the major number 259. Signed-off-by: Mikulas Patocka Cc: Andreas Schwab Cc: Matthew Wilcox Cc: Christoph Hellwig Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- arch/x86/include/asm/compat.h | 6 ++---- fs/stat.c | 19 ++++++++++--------- 2 files changed, 12 insertions(+), 13 deletions(-) diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h index 22c4dfe65992..b4dd6ab0fdfc 100644 --- a/arch/x86/include/asm/compat.h +++ b/arch/x86/include/asm/compat.h @@ -31,15 +31,13 @@ typedef s64 __attribute__((aligned(4))) compat_s64; typedef u64 __attribute__((aligned(4))) compat_u64; struct compat_stat { - compat_dev_t st_dev; - u16 __pad1; + u32 st_dev; compat_ino_t st_ino; compat_mode_t st_mode; compat_nlink_t st_nlink; __compat_uid_t st_uid; __compat_gid_t st_gid; - compat_dev_t st_rdev; - u16 __pad2; + u32 st_rdev; u32 st_size; u32 st_blksize; u32 st_blocks; diff --git a/fs/stat.c b/fs/stat.c index c38e4c2e1221..268c9eb89656 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -290,9 +290,6 @@ SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, stat # define choose_32_64(a,b) b #endif -#define valid_dev(x) choose_32_64(old_valid_dev(x),true) -#define encode_dev(x) choose_32_64(old_encode_dev,new_encode_dev)(x) - #ifndef INIT_STRUCT_STAT_PADDING # define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st)) #endif @@ -301,7 +298,9 @@ static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) { struct stat tmp; - if (!valid_dev(stat->dev) || !valid_dev(stat->rdev)) + if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev)) + return -EOVERFLOW; + if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev)) return -EOVERFLOW; #if BITS_PER_LONG == 32 if (stat->size > MAX_NON_LFS) @@ -309,7 +308,7 @@ static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) #endif INIT_STRUCT_STAT_PADDING(tmp); - tmp.st_dev = encode_dev(stat->dev); + tmp.st_dev = new_encode_dev(stat->dev); tmp.st_ino = stat->ino; if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) return -EOVERFLOW; @@ -319,7 +318,7 @@ static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf) return -EOVERFLOW; SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); - tmp.st_rdev = encode_dev(stat->rdev); + tmp.st_rdev = new_encode_dev(stat->rdev); tmp.st_size = stat->size; tmp.st_atime = stat->atime.tv_sec; tmp.st_mtime = stat->mtime.tv_sec; @@ -593,11 +592,13 @@ static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf) { struct compat_stat tmp; - if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev)) + if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev)) + return -EOVERFLOW; + if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev)) return -EOVERFLOW; memset(&tmp, 0, sizeof(tmp)); - tmp.st_dev = old_encode_dev(stat->dev); + tmp.st_dev = new_encode_dev(stat->dev); tmp.st_ino = stat->ino; if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino) return -EOVERFLOW; @@ -607,7 +608,7 @@ static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf) return -EOVERFLOW; SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid)); SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid)); - tmp.st_rdev = old_encode_dev(stat->rdev); + tmp.st_rdev = new_encode_dev(stat->rdev); if ((u64) stat->size > MAX_NON_LFS) return -EOVERFLOW; tmp.st_size = stat->size; -- 2.35.1