1 files changed, 68 insertions, 78 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 4ea63ed5e791..09ce58e49e72 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -212,8 +212,7 @@ int generic_permission(struct inode *inode, int mask,
          * Read/write DACs are always overridable.
          * Executable DACs are overridable if at least one exec bit is set.
          */
-        if (!(mask & MAY_EXEC) ||
-            (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode))
+        if (!(mask & MAY_EXEC) || execute_ok(inode))
                 if (capable(CAP_DAC_OVERRIDE))
                         return 0;
 
@@ -249,23 +248,11 @@ int inode_permission(struct inode *inode, int mask)
         }
 
         /* Ordinary permission routines do not understand MAY_APPEND. */
-        if (inode->i_op && inode->i_op->permission) {
+        if (inode->i_op && inode->i_op->permission)
                 retval = inode->i_op->permission(inode, mask);
-                if (!retval) {
-                        /*
-                         * Exec permission on a regular file is denied if none
-                         * of the execute bits are set.
-                         *
-                         * This check should be done by the ->permission()
-                         * method.
-                         */
-                        if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) &&
-                            !(inode->i_mode & S_IXUGO))
-                                return -EACCES;
-                }
-        } else {
+        else
                 retval = generic_permission(inode, mask, NULL);
-        }
+
         if (retval)
                 return retval;
 
@@ -1106,6 +1093,15 @@ int path_lookup(const char *name, unsigned int flags,
         return do_path_lookup(AT_FDCWD, name, flags, nd);
 }
 
+int kern_path(const char *name, unsigned int flags, struct path *path)
+{
+        struct nameidata nd;
+        int res = do_path_lookup(AT_FDCWD, name, flags, &nd);
+        if (!res)
+                *path = nd.path;
+        return res;
+}
+
 /**
  * vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair
  * @dentry:  pointer to dentry of the base directory
@@ -1138,9 +1134,16 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt,
 
 }
 
-static int __path_lookup_intent_open(int dfd, const char *name,
-                unsigned int lookup_flags, struct nameidata *nd,
-                int open_flags, int create_mode)
+/**
+ * path_lookup_open - lookup a file path with open intent
+ * @dfd: the directory to use as base, or AT_FDCWD
+ * @name: pointer to file name
+ * @lookup_flags: lookup intent flags
+ * @nd: pointer to nameidata
+ * @open_flags: open intent flags
+ */
+int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
+                struct nameidata *nd, int open_flags)
 {
         struct file *filp = get_empty_filp();
         int err;
@@ -1149,7 +1152,7 @@ static int __path_lookup_intent_open(int dfd, const char *name,
                 return -ENFILE;
         nd->intent.open.file = filp;
         nd->intent.open.flags = open_flags;
-        nd->intent.open.create_mode = create_mode;
+        nd->intent.open.create_mode = 0;
         err = do_path_lookup(dfd, name, lookup_flags|LOOKUP_OPEN, nd);
         if (IS_ERR(nd->intent.open.file)) {
                 if (err == 0) {
@@ -1161,38 +1164,6 @@ static int __path_lookup_intent_open(int dfd, const char *name,
         return err;
 }
 
-/**
- * path_lookup_open - lookup a file path with open intent
- * @dfd: the directory to use as base, or AT_FDCWD
- * @name: pointer to file name
- * @lookup_flags: lookup intent flags
- * @nd: pointer to nameidata
- * @open_flags: open intent flags
- */
-int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
-                struct nameidata *nd, int open_flags)
-{
-        return __path_lookup_intent_open(dfd, name, lookup_flags, nd,
-                        open_flags, 0);
-}
-
-/**
- * path_lookup_create - lookup a file path with open + create intent
- * @dfd: the directory to use as base, or AT_FDCWD
- * @name: pointer to file name
- * @lookup_flags: lookup intent flags
- * @nd: pointer to nameidata
- * @open_flags: open intent flags
- * @create_mode: create intent flags
- */
-static int path_lookup_create(int dfd, const char *name,
-                              unsigned int lookup_flags, struct nameidata *nd,
-                              int open_flags, int create_mode)
-{
-        return __path_lookup_intent_open(dfd, name, lookup_flags|LOOKUP_CREATE,
-                        nd, open_flags, create_mode);
-}
-
 static struct dentry *__lookup_hash(struct qstr *name,
                 struct dentry *base, struct nameidata *nd)
 {
@@ -1470,20 +1441,18 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2)
 
         mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex);
 
-        for (p = p1; p->d_parent != p; p = p->d_parent) {
-                if (p->d_parent == p2) {
-                        mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
-                        mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
-                        return p;
-                }
+        p = d_ancestor(p2, p1);
+        if (p) {
+                mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT);
+                mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD);
+                return p;
         }
 
-        for (p = p2; p->d_parent != p; p = p->d_parent) {
-                if (p->d_parent == p1) {
-                        mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
-                        mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
-                        return p;
-                }
+        p = d_ancestor(p1, p2);
+        if (p) {
+                mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
+                mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD);
+                return p;
         }
 
         mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT);
@@ -1702,8 +1671,7 @@ struct file *do_filp_open(int dfd, const char *pathname,
         /*
          * Create - we need to know the parent.
          */
-        error = path_lookup_create(dfd, pathname, LOOKUP_PARENT,
-                                   &nd, flag, mode);
+        error = do_path_lookup(dfd, pathname, LOOKUP_PARENT, &nd);
         if (error)
                 return ERR_PTR(error);
 
@@ -1714,10 +1682,20 @@ struct file *do_filp_open(int dfd, const char *pathname,
          */
         error = -EISDIR;
         if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len])
-                goto exit;
+                goto exit_parent;
 
+        error = -ENFILE;
+        filp = get_empty_filp();
+        if (filp == NULL)
+                goto exit_parent;
+        nd.intent.open.file = filp;
+        nd.intent.open.flags = flag;
+        nd.intent.open.create_mode = mode;
         dir = nd.path.dentry;
         nd.flags &= ~LOOKUP_PARENT;
+        nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN;
+        if (flag & O_EXCL)
+                nd.flags |= LOOKUP_EXCL;
         mutex_lock(&dir->d_inode->i_mutex);
         path.dentry = lookup_hash(&nd);
         path.mnt = nd.path.mnt;
@@ -1822,6 +1800,7 @@ exit_dput:
 exit:
         if (!IS_ERR(nd.intent.open.file))
                 release_open_intent(&nd);
+exit_parent:
         path_put(&nd.path);
         return ERR_PTR(error);
 
@@ -1914,7 +1893,7 @@ struct dentry *lookup_create(struct nameidata *nd, int is_dir)
         if (nd->last_type != LAST_NORM)
                 goto fail;
         nd->flags &= ~LOOKUP_PARENT;
-        nd->flags |= LOOKUP_CREATE;
+        nd->flags |= LOOKUP_CREATE | LOOKUP_EXCL;
         nd->intent.open.flags = O_EXCL;
 
         /*
@@ -2178,16 +2157,19 @@ static long do_rmdir(int dfd, const char __user *pathname)
                 return error;
 
         switch(nd.last_type) {
-                case LAST_DOTDOT:
-                        error = -ENOTEMPTY;
-                        goto exit1;
-                case LAST_DOT:
-                        error = -EINVAL;
-                        goto exit1;
-                case LAST_ROOT:
-                        error = -EBUSY;
-                        goto exit1;
+        case LAST_DOTDOT:
+                error = -ENOTEMPTY;
+                goto exit1;
+        case LAST_DOT:
+                error = -EINVAL;
+                goto exit1;
+        case LAST_ROOT:
+                error = -EBUSY;
+                goto exit1;
         }
+
+        nd.flags &= ~LOOKUP_PARENT;
+
         mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
         dentry = lookup_hash(&nd);
         error = PTR_ERR(dentry);
@@ -2265,6 +2247,9 @@ static long do_unlinkat(int dfd, const char __user *pathname)
         error = -EISDIR;
         if (nd.last_type != LAST_NORM)
                 goto exit1;
+
+        nd.flags &= ~LOOKUP_PARENT;
+
         mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
         dentry = lookup_hash(&nd);
         error = PTR_ERR(dentry);
@@ -2654,6 +2639,10 @@ asmlinkage long sys_renameat(int olddfd, const char __user *oldname,
         if (newnd.last_type != LAST_NORM)
                 goto exit2;
 
+        oldnd.flags &= ~LOOKUP_PARENT;
+        newnd.flags &= ~LOOKUP_PARENT;
+        newnd.flags |= LOOKUP_RENAME_TARGET;
+
         trap = lock_rename(new_dir, old_dir);
 
         old_dentry = lookup_hash(&oldnd);
@@ -2855,6 +2844,7 @@ EXPORT_SYMBOL(__page_symlink);
 EXPORT_SYMBOL(page_symlink);
 EXPORT_SYMBOL(page_symlink_inode_operations);
 EXPORT_SYMBOL(path_lookup);
+EXPORT_SYMBOL(kern_path);
 EXPORT_SYMBOL(vfs_path_lookup);
 EXPORT_SYMBOL(inode_permission);
 EXPORT_SYMBOL(vfs_permission);