NFS: Ensure we check all allocation return values in new readdir code

Also some clean ups.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 37 insertions, 24 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 2a768d05a534..257e4052492e 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -225,33 +225,42 @@ int nfs_readdir_clear_array(struct page *page, gfp_t mask)
  * nfs_clear_readdir_array()
  */
 static
-void nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int len)
+int nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int len)
 {
         string->len = len;
         string->name = kmemdup(name, len, GFP_KERNEL);
-        string->hash = full_name_hash(string->name, string->len);
+        if (string->name == NULL)
+                return -ENOMEM;
+        string->hash = full_name_hash(name, len);
+        return 0;
 }
 
 static
 int nfs_readdir_add_to_array(struct nfs_entry *entry, struct page *page)
 {
         struct nfs_cache_array *array = nfs_readdir_get_array(page);
+        struct nfs_cache_array_entry *cache_entry;
+        int ret;
+
         if (IS_ERR(array))
                 return PTR_ERR(array);
-        if (array->size >= MAX_READDIR_ARRAY) {
-                nfs_readdir_release_array(page);
-                return -EIO;
-        }
+        ret = -EIO;
+        if (array->size >= MAX_READDIR_ARRAY)
+                goto out;
 
-        array->array[array->size].cookie = entry->prev_cookie;
+        cache_entry = &array->array[array->size];
+        cache_entry->cookie = entry->prev_cookie;
+        cache_entry->ino = entry->ino;
+        ret = nfs_readdir_make_qstr(&cache_entry->string, entry->name, entry->len);
+        if (ret)
+                goto out;
         array->last_cookie = entry->cookie;
-        array->array[array->size].ino = entry->ino;
-        nfs_readdir_make_qstr(&array->array[array->size].string, entry->name, entry->len);
         if (entry->eof == 1)
                 array->eof_index = array->size;
         array->size++;
+out:
         nfs_readdir_release_array(page);
-        return 0;
+        return ret;
 }
 
 static
@@ -388,21 +397,24 @@ different:
 static
 void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 {
-        struct qstr filename;
-        struct dentry *dentry = NULL;
-        struct dentry *alias = NULL;
+        struct qstr filename = {
+                .len = entry->len,
+                .name = entry->name,
+        };
+        struct dentry *dentry;
+        struct dentry *alias;
         struct inode *dir = parent->d_inode;
         struct inode *inode;
 
-        nfs_readdir_make_qstr(&filename, entry->name, entry->len);
-        if (filename.len == 1 && filename.name[0] == '.')
-                dentry = dget(parent);
-        else if (filename.len == 2 && filename.name[0] == '.'
-                                   && filename.name[1] == '.')
-                dentry = dget_parent(parent);
-        else
-                dentry = d_lookup(parent, &filename);
+        if (filename.name[0] == '.') {
+                if (filename.len == 1)
+                        return;
+                if (filename.len == 2 && filename.name[1] == '.')
+                        return;
+        }
+        filename.hash = full_name_hash(filename.name, filename.len);
 
+        dentry = d_lookup(parent, &filename);
         if (dentry != NULL) {
                 if (nfs_same_file(dentry, entry)) {
                         nfs_refresh_inode(dentry->d_inode, entry->fattr);
@@ -414,6 +426,9 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
         }
 
         dentry = d_alloc(parent, &filename);
+        if (dentry == NULL)
+                return;
+
         dentry->d_op = NFS_PROTO(dir)->dentry_ops;
         inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
         if (IS_ERR(inode))
@@ -430,8 +445,6 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 
 out:
         dput(dentry);
-        kfree(filename.name);
-        return;
 }
 
 /* Perform conversion from xdr to cache array */
@@ -508,7 +521,7 @@ void *nfs_readdir_large_page(struct page **pages, unsigned int npages)
                 pages[i] = page;
         }
 
-        ptr = vm_map_ram(pages, NFS_MAX_READDIR_PAGES, 0, PAGE_KERNEL);
+        ptr = vm_map_ram(pages, npages, 0, PAGE_KERNEL);
         if (!IS_ERR_OR_NULL(ptr))
                 return ptr;
 out_freepages: