drop unused dentry argument to ->fsync
[safe/jmp/linux-2.6] / fs / fat / file.c
index c614175..29a5769 100644 (file)
 
 #include <linux/capability.h>
 #include <linux/module.h>
+#include <linux/compat.h>
+#include <linux/mount.h>
 #include <linux/time.h>
-#include <linux/msdos_fs.h>
-#include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
 #include <linux/blkdev.h>
+#include <linux/fsnotify.h>
+#include <linux/security.h>
+#include "fat.h"
 
-int fat_generic_ioctl(struct inode *inode, struct file *filp,
-                     unsigned int cmd, unsigned long arg)
+static int fat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
 {
+       u32 attr;
+
+       mutex_lock(&inode->i_mutex);
+       attr = fat_make_attrs(inode);
+       mutex_unlock(&inode->i_mutex);
+
+       return put_user(attr, user_attr);
+}
+
+static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
+{
+       struct inode *inode = file->f_path.dentry->d_inode;
        struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
-       u32 __user *user_attr = (u32 __user *)arg;
+       int is_dir = S_ISDIR(inode->i_mode);
+       u32 attr, oldattr;
+       struct iattr ia;
+       int err;
 
-       switch (cmd) {
-       case FAT_IOCTL_GET_ATTRIBUTES:
-       {
-               u32 attr;
+       err = get_user(attr, user_attr);
+       if (err)
+               goto out;
 
-               if (inode->i_ino == MSDOS_ROOT_INO)
-                       attr = ATTR_DIR;
-               else
-                       attr = fat_attr(inode);
+       mutex_lock(&inode->i_mutex);
+       err = mnt_want_write(file->f_path.mnt);
+       if (err)
+               goto out_unlock_inode;
 
-               return put_user(attr, user_attr);
+       /*
+        * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
+        * prevents the user from turning us into a VFAT
+        * longname entry.  Also, we obviously can't set
+        * any of the NTFS attributes in the high 24 bits.
+        */
+       attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
+       /* Merge in ATTR_VOLUME and ATTR_DIR */
+       attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
+               (is_dir ? ATTR_DIR : 0);
+       oldattr = fat_make_attrs(inode);
+
+       /* Equivalent to a chmod() */
+       ia.ia_valid = ATTR_MODE | ATTR_CTIME;
+       ia.ia_ctime = current_fs_time(inode->i_sb);
+       if (is_dir)
+               ia.ia_mode = fat_make_mode(sbi, attr, S_IRWXUGO);
+       else {
+               ia.ia_mode = fat_make_mode(sbi, attr,
+                       S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO));
        }
-       case FAT_IOCTL_SET_ATTRIBUTES:
-       {
-               u32 attr, oldattr;
-               int err, is_dir = S_ISDIR(inode->i_mode);
-               struct iattr ia;
 
-               err = get_user(attr, user_attr);
-               if (err)
-                       return err;
-
-               mutex_lock(&inode->i_mutex);
+       /* The root directory has no attributes */
+       if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
+               err = -EINVAL;
+               goto out_drop_write;
+       }
 
-               if (IS_RDONLY(inode)) {
-                       err = -EROFS;
-                       goto up;
-               }
+       if (sbi->options.sys_immutable &&
+           ((attr | oldattr) & ATTR_SYS) &&
+           !capable(CAP_LINUX_IMMUTABLE)) {
+               err = -EPERM;
+               goto out_drop_write;
+       }
 
-               /*
-                * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
-                * prevents the user from turning us into a VFAT
-                * longname entry.  Also, we obviously can't set
-                * any of the NTFS attributes in the high 24 bits.
-                */
-               attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
-               /* Merge in ATTR_VOLUME and ATTR_DIR */
-               attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
-                       (is_dir ? ATTR_DIR : 0);
-               oldattr = fat_attr(inode);
-
-               /* Equivalent to a chmod() */
-               ia.ia_valid = ATTR_MODE | ATTR_CTIME;
-               if (is_dir) {
-                       ia.ia_mode = MSDOS_MKMODE(attr,
-                               S_IRWXUGO & ~sbi->options.fs_dmask)
-                               | S_IFDIR;
-               } else {
-                       ia.ia_mode = MSDOS_MKMODE(attr,
-                               (S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO))
-                               & ~sbi->options.fs_fmask)
-                               | S_IFREG;
-               }
+       /*
+        * The security check is questionable...  We single
+        * out the RO attribute for checking by the security
+        * module, just because it maps to a file mode.
+        */
+       err = security_inode_setattr(file->f_path.dentry, &ia);
+       if (err)
+               goto out_drop_write;
 
-               /* The root directory has no attributes */
-               if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
-                       err = -EINVAL;
-                       goto up;
-               }
+       /* This MUST be done before doing anything irreversible... */
+       err = fat_setattr(file->f_path.dentry, &ia);
+       if (err)
+               goto out_drop_write;
 
-               if (sbi->options.sys_immutable) {
-                       if ((attr | oldattr) & ATTR_SYS) {
-                               if (!capable(CAP_LINUX_IMMUTABLE)) {
-                                       err = -EPERM;
-                                       goto up;
-                               }
-                       }
-               }
+       fsnotify_change(file->f_path.dentry, ia.ia_valid);
+       if (sbi->options.sys_immutable) {
+               if (attr & ATTR_SYS)
+                       inode->i_flags |= S_IMMUTABLE;
+               else
+                       inode->i_flags &= S_IMMUTABLE;
+       }
 
-               /* This MUST be done before doing anything irreversible... */
-               err = notify_change(filp->f_path.dentry, &ia);
-               if (err)
-                       goto up;
+       fat_save_attrs(inode, attr);
+       mark_inode_dirty(inode);
+out_drop_write:
+       mnt_drop_write(file->f_path.mnt);
+out_unlock_inode:
+       mutex_unlock(&inode->i_mutex);
+out:
+       return err;
+}
 
-               if (sbi->options.sys_immutable) {
-                       if (attr & ATTR_SYS)
-                               inode->i_flags |= S_IMMUTABLE;
-                       else
-                               inode->i_flags &= S_IMMUTABLE;
-               }
+long fat_generic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+       struct inode *inode = filp->f_path.dentry->d_inode;
+       u32 __user *user_attr = (u32 __user *)arg;
 
-               MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED;
-               mark_inode_dirty(inode);
-       up:
-               mutex_unlock(&inode->i_mutex);
-               return err;
-       }
+       switch (cmd) {
+       case FAT_IOCTL_GET_ATTRIBUTES:
+               return fat_ioctl_get_attributes(inode, user_attr);
+       case FAT_IOCTL_SET_ATTRIBUTES:
+               return fat_ioctl_set_attributes(filp, user_attr);
        default:
                return -ENOTTY; /* Inappropriate ioctl for device */
        }
 }
 
+#ifdef CONFIG_COMPAT
+static long fat_generic_compat_ioctl(struct file *filp, unsigned int cmd,
+                                     unsigned long arg)
+
+{
+       return fat_generic_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
 static int fat_file_release(struct inode *inode, struct file *filp)
 {
        if ((filp->f_mode & FMODE_WRITE) &&
             MSDOS_SB(inode->i_sb)->options.flush) {
                fat_flush_inodes(inode->i_sb, inode, NULL);
-               congestion_wait(WRITE, HZ/10);
+               congestion_wait(BLK_RW_ASYNC, HZ/10);
        }
        return 0;
 }
 
+int fat_file_fsync(struct file *filp, int datasync)
+{
+       struct inode *inode = filp->f_mapping->host;
+       int res, err;
+
+       res = simple_fsync(filp, datasync);
+       err = sync_mapping_buffers(MSDOS_SB(inode->i_sb)->fat_inode->i_mapping);
+
+       return res ? res : err;
+}
+
+
 const struct file_operations fat_file_operations = {
        .llseek         = generic_file_llseek,
        .read           = do_sync_read,
@@ -132,8 +169,11 @@ const struct file_operations fat_file_operations = {
        .aio_write      = generic_file_aio_write,
        .mmap           = generic_file_mmap,
        .release        = fat_file_release,
-       .ioctl          = fat_generic_ioctl,
-       .fsync          = file_fsync,
+       .unlocked_ioctl = fat_generic_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl   = fat_generic_compat_ioctl,
+#endif
+       .fsync          = fat_file_fsync,
        .splice_read    = generic_file_splice_read,
 };
 
@@ -149,110 +189,30 @@ static int fat_cont_expand(struct inode *inode, loff_t size)
 
        inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
        mark_inode_dirty(inode);
-       if (IS_SYNC(inode))
-               err = sync_page_range_nolock(inode, mapping, start, count);
-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 (IS_SYNC(inode)) {
+               int err2;
 
-               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;
+               /*
+                * Opencode syncing since we don't have a file open to use
+                * standard fsync path.
+                */
+               err = filemap_fdatawrite_range(mapping, start,
+                                              start + count - 1);
+               err2 = sync_mapping_buffers(mapping);
+               if (!err)
+                       err = err2;
+               err2 = write_inode_now(inode, 1);
+               if (!err)
+                       err = err2;
+               if (!err) {
+                       err =  filemap_fdatawait_range(mapping, start,
+                                                      start + count - 1);
                }
        }
-
-       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;
+       return err;
 }
 
-EXPORT_SYMBOL_GPL(fat_notify_change);
-
 /* Free all clusters after the skip'th cluster. */
 static int fat_free(struct inode *inode, int skip)
 {
@@ -302,9 +262,9 @@ static int fat_free(struct inode *inode, int skip)
                        fatent_brelse(&fatent);
                        return 0;
                } else if (ret == FAT_ENT_FREE) {
-                       fat_fs_panic(sb,
+                       fat_fs_error(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);
@@ -338,9 +298,7 @@ void fat_truncate(struct inode *inode)
 
        nr_clusters = (inode->i_size + (cluster_size - 1)) >> sbi->cluster_bits;
 
-       lock_kernel();
        fat_free(inode, nr_clusters);
-       unlock_kernel();
        fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
@@ -353,8 +311,131 @@ 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 & ~FAT_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 fat_mode_can_hold_ro(inode) is false, can't change w bits.
+        */
+       if ((perm & (S_IRUGO | S_IXUGO)) != (inode->i_mode & (S_IRUGO|S_IXUGO)))
+               return -EPERM;
+       if (fat_mode_can_hold_ro(inode)) {
+               if ((perm & S_IWUGO) && ((perm & S_IWUGO) != (S_IWUGO & ~mask)))
+                       return -EPERM;
+       } else {
+               if ((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;
+}
+
+#define TIMES_SET_FLAGS        (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)
+/* valid file mode bits */
+#define FAT_VALID_MODE (S_IFREG | S_IFDIR | S_IRWXUGO)
+
+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;
+       unsigned int ia_valid;
+       int error;
+
+       /*
+        * 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 & TIMES_SET_FLAGS) {
+               if (fat_allow_set_time(sbi, inode))
+                       attr->ia_valid &= ~TIMES_SET_FLAGS;
+       }
+
+       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 & ~FAT_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;
+       }
+
+       if (attr->ia_valid)
+               error = inode_setattr(inode, attr);
+out:
+       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,
 };