Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755920AbYJOOGg (ORCPT ); Wed, 15 Oct 2008 10:06:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753769AbYJOOEw (ORCPT ); Wed, 15 Oct 2008 10:04:52 -0400 Received: from mail.parknet.ad.jp ([210.171.162.6]:45116 "EHLO mail.officemail.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752100AbYJOOEs (ORCPT ); Wed, 15 Oct 2008 10:04:48 -0400 Subject: [PATCH 15/21] fat: Fix ATTR_RO in the case of (~umask & S_WUGO) == 0 To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, hirofumi@mail.parknet.co.jp From: OGAWA Hirofumi Date: Wed, 15 Oct 2008 22:58:00 +0900 Message-ID: References: <4e3b7e0f3e848f5f6e4222369.ps@mail.parknet.co.jp> <0f24bbb03e848f5f6e5322369.ps@mail.parknet.co.jp> <2dbbb6ea3e848f5f6e5422369.ps@mail.parknet.co.jp> <3adb30833e848f5f6e5522369.ps@mail.parknet.co.jp> <091baa8f3e848f5f6e6722369.ps@mail.parknet.co.jp> <649ecd633e848f5f6e6822369.ps@mail.parknet.co.jp> <2f7c69713e848f5f6e6922369.ps@mail.parknet.co.jp> <6caa18733e848f5f6e71122369.ps@mail.parknet.co.jp> <5cfc12333e848f5f6e71322369.ps@mail.parknet.co.jp> <6b812e3e3e848f5f6e81422369.ps@mail.parknet.co.jp> In-Reply-To: <6b812e3e3e848f5f6e81422369.ps@mail.parknet.co.jp> X-Anti-Virus: Kaspersky Anti-Virus for MailServers 5.5.10/RELEASE, bases: 24052007 #308098, status: clean Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3341 Lines: 100 If inode->i_mode doesn't have S_WUGO, current code assumes it means ATTR_RO. However, if (~[ufd]mask & S_WUGO) == 0, inode->i_mode can't hold S_WUGO. Therefore the updated directory entry will always have ATTR_RO. This adds fat_mode_can_hold_ro() to check it. And if inode->i_mode can't hold, uses -i_attrs to hold ATTR_RO instead. With this, we don't set ATTR_RO unless users change it via ioctl() if (~[ufd]mask & S_WUGO) == 0. And on FAT_IOCTL_GET_ATTRIBUTES path, this adds ->i_mutex to it for not returning the partially updated attributes by FAT_IOCTL_SET_ATTRIBUTES to userland. Signed-off-by: OGAWA Hirofumi --- fs/fat/fat.h | 33 +++++++++++++++++++++++++++++---- fs/fat/file.c | 7 ++++++- 2 files changed, 35 insertions(+), 5 deletions(-) diff -puN fs/fat/fat.h~fat-attrs-fixes fs/fat/fat.h --- linux-2.6/fs/fat/fat.h~fat-attrs-fixes 2008-10-13 01:49:49.000000000 +0900 +++ linux-2.6-hirofumi/fs/fat/fat.h 2008-10-13 01:49:49.000000000 +0900 @@ -117,6 +117,25 @@ static inline struct msdos_inode_info *M return container_of(inode, struct msdos_inode_info, vfs_inode); } +/* + * If ->i_mode can't hold S_IWUGO (i.e. ATTR_RO), we use ->i_attrs to + * save ATTR_RO instead of ->i_mode. + */ +static inline int fat_mode_can_hold_ro(struct inode *inode) +{ + struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); + mode_t mask; + + if (S_ISDIR(inode->i_mode)) + mask = ~sbi->options.fs_dmask; + else + mask = ~sbi->options.fs_fmask; + + if (!(mask & S_IWUGO)) + return 0; + return 1; +} + /* Convert attribute bits and a mask to the UNIX mode. */ static inline mode_t fat_make_mode(struct msdos_sb_info *sbi, u8 attrs, mode_t mode) @@ -133,14 +152,20 @@ static inline mode_t fat_make_mode(struc /* Return the FAT attribute byte for this inode */ static inline u8 fat_make_attrs(struct inode *inode) { - return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) | - (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) | - MSDOS_I(inode)->i_attrs; + u8 attrs = MSDOS_I(inode)->i_attrs; + if (S_ISDIR(inode->i_mode)) + attrs |= ATTR_DIR; + if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO)) + attrs |= ATTR_RO; + return attrs; } static inline void fat_save_attrs(struct inode *inode, u8 attrs) { - MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED; + if (fat_mode_can_hold_ro(inode)) + MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED; + else + MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO); } static inline unsigned char fat_checksum(const __u8 *name) diff -puN fs/fat/file.c~fat-attrs-fixes fs/fat/file.c --- linux-2.6/fs/fat/file.c~fat-attrs-fixes 2008-10-13 01:49:49.000000000 +0900 +++ linux-2.6-hirofumi/fs/fat/file.c 2008-10-13 01:49:49.000000000 +0900 @@ -27,7 +27,12 @@ int fat_generic_ioctl(struct inode *inod switch (cmd) { case FAT_IOCTL_GET_ATTRIBUTES: { - u32 attr = fat_make_attrs(inode); + u32 attr; + + mutex_lock(&inode->i_mutex); + attr = fat_make_attrs(inode); + mutex_unlock(&inode->i_mutex); + return put_user(attr, user_attr); } case FAT_IOCTL_SET_ATTRIBUTES: _ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/