ovl: fix check for cursor

ovl_cache_entry.name is now an array not a pointer, so it makes no sense
test for it being NULL.

Detected by coverity.

From: Miklos Szeredi <mszeredi@suse.cz>
Fixes: 68bf8611076a ("overlayfs: make ovl_cache_entry->name an array instead of
+pointer")
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 5 deletions

diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 8c8ce9d87ba3..3fbf0d306e12 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -21,9 +21,10 @@ struct ovl_cache_entry {
         unsigned int len;
         unsigned int type;
         u64 ino;
-        bool is_whiteout;
         struct list_head l_node;
         struct rb_node node;
+        bool is_whiteout;
+        bool is_cursor;
         char name[];
 };
 
@@ -251,7 +252,7 @@ static int ovl_dir_mark_whiteouts(struct dentry *dir,
 
         mutex_lock(&dir->d_inode->i_mutex);
         list_for_each_entry(p, rdd->list, l_node) {
-                if (!p->name)
+                if (p->is_cursor)
                         continue;
 
                 if (p->type != DT_CHR)
@@ -307,7 +308,6 @@ static inline int ovl_dir_read_merged(struct path *upperpath,
         }
 out:
         return err;
-
 }
 
 static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
@@ -316,7 +316,7 @@ static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
         loff_t off = 0;
 
         list_for_each_entry(p, &od->cache->entries, l_node) {
-                if (!p->name)
+                if (p->is_cursor)
                         continue;
                 if (off >= pos)
                         break;
@@ -389,7 +389,7 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx)
 
                 p = list_entry(od->cursor.l_node.next, struct ovl_cache_entry, l_node);
                 /* Skip cursors */
-                if (p->name) {
+                if (!p->is_cursor) {
                         if (!p->is_whiteout) {
                                 if (!dir_emit(ctx, p->name, p->len, p->ino, p->type))
                                         break;
@@ -519,6 +519,7 @@ static int ovl_dir_open(struct inode *inode, struct file *file)
         od->realfile = realfile;
         od->is_real = (type != OVL_PATH_MERGE);
         od->is_upper = (type != OVL_PATH_LOWER);
+        od->cursor.is_cursor = true;
         file->private_data = od;
 
         return 0;