From 1ae43f826b6cb951fc5b0f9c92372a8d5b63c7f9 Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Mon, 28 Apr 2008 02:16:26 -0700 Subject: fat: Add allow_utime option Normally utime(2) checks current process is owner of the file, or it has CAP_FOWNER capability. But FAT filesystem doesn't have uid/gid as on disk info, so normal check is too unflexible. With this option you can relax it. Signed-off-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/file.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'fs/fat/file.c') diff --git a/fs/fat/file.c b/fs/fat/file.c index e73f13a1379..d604bb13242 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -280,11 +280,27 @@ static int fat_check_mode(const struct msdos_sb_info *sbi, struct inode *inode, return 0; } +static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode) +{ + mode_t allow_utime = sbi->options.allow_utime; + + if (current->fsuid != inode->i_uid) { + if (in_group_p(inode->i_gid)) + allow_utime >>= 3; + if (allow_utime & MAY_WRITE) + return 1; + } + + /* use a default check */ + return 0; +} + int fat_setattr(struct dentry *dentry, struct iattr *attr) { struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb); struct inode *inode = dentry->d_inode; int mask, error = 0; + unsigned int ia_valid; lock_kernel(); @@ -302,7 +318,15 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr) } } + /* Check for setting the inode time. */ + ia_valid = attr->ia_valid; + if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) { + if (fat_allow_set_time(sbi, inode)) + attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET); + } + error = inode_change_ok(inode, attr); + attr->ia_valid = ia_valid; if (error) { if (sbi->options.quiet) error = 0; -- cgit v1.2.3