Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[pandora-kernel.git] / fs / fat / file.c

diff --git a/fs/fat/file.c b/fs/fat/file.c
index 55d3c74..2a3bed9 100644 (file)
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -8,6 +8,7 @@
 
 #include <linux/capability.h>
 #include <linux/module.h>
+#include <linux/mount.h>
 #include <linux/time.h>
 #include <linux/msdos_fs.h>
 #include <linux/smp_lock.h>
@@ -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;
        }
@@ -134,7 +136,7 @@ const struct file_operations fat_file_operations = {
        .release        = fat_file_release,
        .ioctl          = fat_generic_ioctl,
        .fsync          = file_fsync,
-       .sendfile       = generic_file_sendfile,
+       .splice_read    = generic_file_splice_read,
 };
 
 static int fat_cont_expand(struct inode *inode, loff_t size)
@@ -155,6 +157,42 @@ 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);
@@ -186,9 +224,7 @@ int fat_notify_change(struct dentry *dentry, struct iattr *attr)
        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)))
+            (attr->ia_gid != sbi->options.fs_gid)))
                error = -EPERM;
 
        if (error) {
@@ -196,6 +232,13 @@ int fat_notify_change(struct dentry *dentry, struct iattr *attr)
                        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;