X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Ffat%2Ffile.c;h=771326b8047e0ff5e3483f885c1edc30a604471a;hb=6ba33ac8a47d33d0b5996d24ddf66c457cd7180b;hp=c614175876e09316ea0a36566dc072fe6819169c;hpb=c58310bf4933986513020fa90b4190c7492995ae;p=linux-2.6-omap-h63xx.git diff --git a/fs/fat/file.c b/fs/fat/file.c index c614175876e..771326b8047 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -8,6 +8,7 @@ #include #include +#include #include #include #include @@ -46,10 +47,9 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp, mutex_lock(&inode->i_mutex); - if (IS_RDONLY(inode)) { - err = -EROFS; - goto up; - } + err = mnt_want_write(filp->f_path.mnt); + if (err) + goto up_no_drop_write; /* * ATTR_VOLUME and ATTR_DIR cannot be changed; this also @@ -105,7 +105,9 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp, MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED; mark_inode_dirty(inode); - up: +up: + mnt_drop_write(filp->f_path.mnt); +up_no_drop_write: mutex_unlock(&inode->i_mutex); return err; } @@ -155,104 +157,6 @@ out: return err; } -static int check_mode(const struct msdos_sb_info *sbi, mode_t mode) -{ - mode_t req = mode & ~S_IFMT; - - /* - * Of the r and x bits, all (subject to umask) must be present. Of the - * w bits, either all (subject to umask) or none must be present. - */ - - if (S_ISREG(mode)) { - req &= ~sbi->options.fs_fmask; - - if ((req & (S_IRUGO | S_IXUGO)) != - ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_fmask)) - return -EPERM; - - if ((req & S_IWUGO) != 0 && - (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_fmask)) - return -EPERM; - } else if (S_ISDIR(mode)) { - req &= ~sbi->options.fs_dmask; - - if ((req & (S_IRUGO | S_IXUGO)) != - ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_dmask)) - return -EPERM; - - if ((req & S_IWUGO) != 0 && - (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_dmask)) - return -EPERM; - } else { - return -EPERM; - } - - return 0; -} - -int fat_notify_change(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; - - lock_kernel(); - - /* - * Expand the file. Since inode_setattr() updates ->i_size - * before calling the ->truncate(), but FAT needs to fill the - * hole before it. - */ - if (attr->ia_valid & ATTR_SIZE) { - if (attr->ia_size > inode->i_size) { - error = fat_cont_expand(inode, attr->ia_size); - if (error || attr->ia_valid == ATTR_SIZE) - goto out; - attr->ia_valid &= ~ATTR_SIZE; - } - } - - error = inode_change_ok(inode, attr); - if (error) { - if (sbi->options.quiet) - error = 0; - goto out; - } - if (((attr->ia_valid & ATTR_UID) && - (attr->ia_uid != sbi->options.fs_uid)) || - ((attr->ia_valid & ATTR_GID) && - (attr->ia_gid != sbi->options.fs_gid))) - error = -EPERM; - - if (error) { - if (sbi->options.quiet) - error = 0; - goto out; - } - - if (attr->ia_valid & ATTR_MODE) { - error = check_mode(sbi, attr->ia_mode); - if (error != 0 && !sbi->options.quiet) - goto out; - } - - error = inode_setattr(inode, attr); - if (error) - goto out; - - if (S_ISDIR(inode->i_mode)) - mask = sbi->options.fs_dmask; - else - mask = sbi->options.fs_fmask; - inode->i_mode &= S_IFMT | (S_IRWXUGO & ~mask); -out: - unlock_kernel(); - return error; -} - -EXPORT_SYMBOL_GPL(fat_notify_change); - /* Free all clusters after the skip'th cluster. */ static int fat_free(struct inode *inode, int skip) { @@ -304,7 +208,7 @@ static int fat_free(struct inode *inode, int skip) } else if (ret == FAT_ENT_FREE) { fat_fs_panic(sb, "%s: invalid cluster chain (i_pos %lld)", - __FUNCTION__, MSDOS_I(inode)->i_pos); + __func__, MSDOS_I(inode)->i_pos); ret = -EIO; } else if (ret > 0) { err = fat_ent_write(inode, &fatent, FAT_ENT_EOF, wait); @@ -353,8 +257,122 @@ int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) } EXPORT_SYMBOL_GPL(fat_getattr); +static int fat_sanitize_mode(const struct msdos_sb_info *sbi, + struct inode *inode, umode_t *mode_ptr) +{ + mode_t mask, perm; + + /* + * Note, the basic check is already done by a caller of + * (attr->ia_mode & ~MSDOS_VALID_MODE) + */ + + if (S_ISREG(inode->i_mode)) + mask = sbi->options.fs_fmask; + else + mask = sbi->options.fs_dmask; + + perm = *mode_ptr & ~(S_IFMT | mask); + + /* + * Of the r and x bits, all (subject to umask) must be present. Of the + * w bits, either all (subject to umask) or none must be present. + */ + if ((perm & (S_IRUGO | S_IXUGO)) != (inode->i_mode & (S_IRUGO|S_IXUGO))) + return -EPERM; + if ((perm & S_IWUGO) && ((perm & S_IWUGO) != (S_IWUGO & ~mask))) + return -EPERM; + + *mode_ptr &= S_IFMT | perm; + + 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 error = 0; + unsigned int ia_valid; + + lock_kernel(); + + /* + * Expand the file. Since inode_setattr() updates ->i_size + * before calling the ->truncate(), but FAT needs to fill the + * hole before it. + */ + if (attr->ia_valid & ATTR_SIZE) { + if (attr->ia_size > inode->i_size) { + error = fat_cont_expand(inode, attr->ia_size); + if (error || attr->ia_valid == ATTR_SIZE) + goto out; + attr->ia_valid &= ~ATTR_SIZE; + } + } + + /* 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; + goto out; + } + + if (((attr->ia_valid & ATTR_UID) && + (attr->ia_uid != sbi->options.fs_uid)) || + ((attr->ia_valid & ATTR_GID) && + (attr->ia_gid != sbi->options.fs_gid)) || + ((attr->ia_valid & ATTR_MODE) && + (attr->ia_mode & ~MSDOS_VALID_MODE))) + error = -EPERM; + + if (error) { + if (sbi->options.quiet) + error = 0; + goto out; + } + + /* + * We don't return -EPERM here. Yes, strange, but this is too + * old behavior. + */ + if (attr->ia_valid & ATTR_MODE) { + if (fat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0) + attr->ia_valid &= ~ATTR_MODE; + } + + error = inode_setattr(inode, attr); +out: + unlock_kernel(); + return error; +} +EXPORT_SYMBOL_GPL(fat_setattr); + const struct inode_operations fat_file_inode_operations = { .truncate = fat_truncate, - .setattr = fat_notify_change, + .setattr = fat_setattr, .getattr = fat_getattr, };