[patch 4/5] vfs: reuse local variable in vfs_link()

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

diff --git a/fs/namei.c b/fs/namei.c
index 01e67dddcc3d2033a2038c37f9f791ba0921a781..3b67be7631dc21b4d76bb4e2ee45b486eb0bb720 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -185,6 +185,8 @@ int generic_permission(struct inode *inode, int mask,
 {
        umode_t                 mode = inode->i_mode;
 
+       mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
+
        if (current->fsuid == inode->i_uid)
                mode >>= 6;
        else {
@@ -203,7 +205,7 @@ int generic_permission(struct inode *inode, int mask,
        /*
         * If the DACs are ok we don't need any capability check.
         */
-       if (((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask))
+       if ((mask & ~mode) == 0)
                return 0;
 
  check_capabilities:
@@ -228,7 +230,7 @@ int generic_permission(struct inode *inode, int mask,
 
 int permission(struct inode *inode, int mask, struct nameidata *nd)
 {
-       int retval, submask;
+       int retval;
        struct vfsmount *mnt = NULL;
 
        if (nd)
@@ -261,9 +263,17 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
        }
 
        /* Ordinary permission routines do not understand MAY_APPEND. */
-       submask = mask & ~MAY_APPEND;
        if (inode->i_op && inode->i_op->permission) {
-               retval = inode->i_op->permission(inode, submask, nd);
+               int extra = 0;
+               if (nd) {
+                       if (nd->flags & LOOKUP_ACCESS)
+                               extra |= MAY_ACCESS;
+                       if (nd->flags & LOOKUP_CHDIR)
+                               extra |= MAY_CHDIR;
+                       if (nd->flags & LOOKUP_OPEN)
+                               extra |= MAY_OPEN;
+               }
+               retval = inode->i_op->permission(inode, mask | extra);
                if (!retval) {
                        /*
                         * Exec permission on a regular file is denied if none
@@ -277,7 +287,7 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
                                return -EACCES;
                }
        } else {
-               retval = generic_permission(inode, submask, NULL);
+               retval = generic_permission(inode, mask, NULL);
        }
        if (retval)
                return retval;
@@ -286,7 +296,8 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
        if (retval)
                return retval;
 
-       return security_inode_permission(inode, mask, nd);
+       return security_inode_permission(inode,
+                       mask & (MAY_READ|MAY_WRITE|MAY_EXEC), nd);
 }
 
 /**
@@ -519,7 +530,14 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
         */
        result = d_lookup(parent, name);
        if (!result) {
-               struct dentry * dentry = d_alloc(parent, name);
+               struct dentry *dentry;
+
+               /* Don't create child dentry for a dead directory. */
+               result = ERR_PTR(-ENOENT);
+               if (IS_DEADDIR(dir))
+                       goto out_unlock;
+
+               dentry = d_alloc(parent, name);
                result = ERR_PTR(-ENOMEM);
                if (dentry) {
                        result = dir->i_op->lookup(dir, dentry, nd);
@@ -528,6 +546,7 @@ static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, s
                        else
                                result = dentry;
                }
+out_unlock:
                mutex_unlock(&dir->i_mutex);
                return result;
        }
@@ -1317,7 +1336,14 @@ static struct dentry *__lookup_hash(struct qstr *name,
 
        dentry = cached_lookup(base, name, nd);
        if (!dentry) {
-               struct dentry *new = d_alloc(base, name);
+               struct dentry *new;
+
+               /* Don't create child dentry for a dead directory. */
+               dentry = ERR_PTR(-ENOENT);
+               if (IS_DEADDIR(inode))
+                       goto out;
+
+               new = d_alloc(base, name);
                dentry = ERR_PTR(-ENOMEM);
                if (!new)
                        goto out;
@@ -2498,19 +2524,19 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
                return -EPERM;
        if (!dir->i_op || !dir->i_op->link)
                return -EPERM;
-       if (S_ISDIR(old_dentry->d_inode->i_mode))
+       if (S_ISDIR(inode->i_mode))
                return -EPERM;
 
        error = security_inode_link(old_dentry, dir, new_dentry);
        if (error)
                return error;
 
-       mutex_lock(&old_dentry->d_inode->i_mutex);
+       mutex_lock(&inode->i_mutex);
        DQUOT_INIT(dir);
        error = dir->i_op->link(old_dentry, dir, new_dentry);
-       mutex_unlock(&old_dentry->d_inode->i_mutex);
+       mutex_unlock(&inode->i_mutex);
        if (!error)
-               fsnotify_link(dir, old_dentry->d_inode, new_dentry);
+               fsnotify_link(dir, inode, new_dentry);
        return error;
 }