fuse: clean up execute permission checking

Define a new function fuse_refresh_attributes() that conditionally refreshes
the attributes based on the validity timeout.

In fuse_permission() only refresh the attributes for checking the execute bits
if necessary.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 8ea4ea13ec5fb5f50d107d3c4f3c41003ba76ef3..d1acab931330ba8744058482c1ff5a50e753c62d 100644 (file)
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -694,6 +694,20 @@ static int fuse_do_getattr(struct inode *inode)
        return err;
 }
 
+/*
+ * Check if attributes are still valid, and if not send a GETATTR
+ * request to refresh them.
+ */
+static int fuse_refresh_attributes(struct inode *inode)
+{
+       struct fuse_inode *fi = get_fuse_inode(inode);
+
+       if (fi->i_time < get_jiffies_64())
+               return fuse_do_getattr(inode);
+       else
+               return 0;
+}
+
 /*
  * Calling into a user-controlled filesystem gives the filesystem
  * daemon ptrace-like capabilities over the requester process.  This
@@ -770,7 +784,6 @@ static int fuse_access(struct inode *inode, int mask)
 static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
 {
        struct fuse_conn *fc = get_fuse_conn(inode);
-       struct fuse_inode *fi = get_fuse_inode(inode);
        bool refreshed = false;
        int err = 0;
 
@@ -778,12 +791,11 @@ static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
                return -EACCES;
 
        /*
-        * If attributes are needed, but are stale, refresh them
-        * before proceeding
+        * If attributes are needed, refresh them before proceeding
         */
-       if (((fc->flags & FUSE_DEFAULT_PERMISSIONS) || (mask & MAY_EXEC)) &&
-           fi->i_time < get_jiffies_64()) {
-               err = fuse_do_getattr(inode);
+       if ((fc->flags & FUSE_DEFAULT_PERMISSIONS) ||
+           ((mask & MAY_EXEC) && S_ISREG(inode->i_mode))) {
+               err = fuse_refresh_attributes(inode);
                if (err)
                        return err;
 
@@ -806,14 +818,17 @@ static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
                   exist.  So if permissions are revoked this won't be
                   noticed immediately, only after the attribute
                   timeout has expired */
-
-       } else {
-               int mode = inode->i_mode;
-               if ((mask & MAY_EXEC) && !S_ISDIR(mode) && !(mode & S_IXUGO))
-                       return -EACCES;
-
-               if (nd && (nd->flags & (LOOKUP_ACCESS | LOOKUP_CHDIR)))
-                       return fuse_access(inode, mask);
+       } else if (nd && (nd->flags & (LOOKUP_ACCESS | LOOKUP_CHDIR))) {
+               err = fuse_access(inode, mask);
+       } else if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) {
+               if (!(inode->i_mode & S_IXUGO)) {
+                       if (refreshed)
+                               return -EACCES;
+
+                       err = fuse_do_getattr(inode);
+                       if (!err && !(inode->i_mode & S_IXUGO))
+                               return -EACCES;
+               }
        }
        return err;
 }
@@ -1046,14 +1061,12 @@ static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
        struct inode *inode = entry->d_inode;
        struct fuse_inode *fi = get_fuse_inode(inode);
        struct fuse_conn *fc = get_fuse_conn(inode);
-       int err = 0;
+       int err;
 
        if (!fuse_allow_task(fc, current))
                return -EACCES;
 
-       if (fi->i_time < get_jiffies_64())
-               err = fuse_do_getattr(inode);
-
+       err = fuse_refresh_attributes(inode);
        if (!err) {
                generic_fillattr(inode, stat);
                stat->mode = fi->orig_i_mode;