fat: Fix ATTR_RO for directory

[linux-2.6-omap-h63xx.git] / fs / fat / file.c

diff --git a/fs/fat/file.c b/fs/fat/file.c
index 8707a8cfa02cdd8454056ed320ee49a4604c84f8..f06a4e525eceff2b758ba0ff62ebd6e6f2fca9bb 100644 (file)
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -10,13 +10,13 @@
 #include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/time.h>
-#include <linux/msdos_fs.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)
@@ -29,10 +29,9 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
        {
                u32 attr;
 
-               if (inode->i_ino == MSDOS_ROOT_INO)
-                       attr = ATTR_DIR;
-               else
-                       attr = fat_attr(inode);
+               mutex_lock(&inode->i_mutex);
+               attr = fat_make_attrs(inode);
+               mutex_unlock(&inode->i_mutex);
 
                return put_user(attr, user_attr);
        }
@@ -62,20 +61,16 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
                /* Merge in ATTR_VOLUME and ATTR_DIR */
                attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
                        (is_dir ? ATTR_DIR : 0);
-               oldattr = fat_attr(inode);
+               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 = 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;
+               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));
                }
 
                /* The root directory has no attributes */
@@ -115,7 +110,7 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
                                inode->i_flags &= S_IMMUTABLE;
                }
 
-               MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED;
+               fat_save_attrs(inode, attr);
                mark_inode_dirty(inode);
 up:
                mnt_drop_write(filp->f_path.mnt);
@@ -274,7 +269,7 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
 
        /*
         * Note, the basic check is already done by a caller of
-        * (attr->ia_mode & ~MSDOS_VALID_MODE)
+        * (attr->ia_mode & ~FAT_VALID_MODE)
         */
 
        if (S_ISREG(inode->i_mode))
@@ -287,11 +282,18 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
        /*
         * 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 ((perm & S_IWUGO) && ((perm & S_IWUGO) != (S_IWUGO & ~mask)))
-               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;
 
@@ -313,12 +315,16 @@ static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
        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;
-       int error = 0;
        unsigned int ia_valid;
+       int error;
 
        /*
         * Expand the file. Since inode_setattr() updates ->i_size
@@ -336,9 +342,9 @@ 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 (ia_valid & TIMES_SET_FLAGS) {
                if (fat_allow_set_time(sbi, inode))
-                       attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET);
+                       attr->ia_valid &= ~TIMES_SET_FLAGS;
        }
 
        error = inode_change_ok(inode, attr);
@@ -354,7 +360,7 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
            ((attr->ia_valid & ATTR_GID) &&
             (attr->ia_gid != sbi->options.fs_gid)) ||
            ((attr->ia_valid & ATTR_MODE) &&
-            (attr->ia_mode & ~MSDOS_VALID_MODE)))
+            (attr->ia_mode & ~FAT_VALID_MODE)))
                error = -EPERM;
 
        if (error) {
@@ -372,7 +378,8 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
                        attr->ia_valid &= ~ATTR_MODE;
        }
 
-       error = inode_setattr(inode, attr);
+       if (attr->ia_valid)
+               error = inode_setattr(inode, attr);
 out:
        return error;
 }