1 files changed, 91 insertions, 11 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 2c3eb33b904d..7237672216c8 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -44,6 +44,7 @@
 /* #define NFS_DEBUG_VERBOSE 1 */
 
 static int nfs_opendir(struct inode *, struct file *);
+static int nfs_closedir(struct inode *, struct file *);
 static int nfs_readdir(struct file *, void *, filldir_t);
 static struct dentry *nfs_lookup(struct inode *, struct dentry *, struct nameidata *);
 static int nfs_create(struct inode *, struct dentry *, int, struct nameidata *);
@@ -64,7 +65,7 @@ const struct file_operations nfs_dir_operations = {
         .read           = generic_read_dir,
         .readdir        = nfs_readdir,
         .open           = nfs_opendir,
-        .release        = nfs_release,
+        .release        = nfs_closedir,
         .fsync          = nfs_fsync_dir,
 };
 
@@ -133,13 +134,35 @@ const struct inode_operations nfs4_dir_inode_operations = {
 
 #endif /* CONFIG_NFS_V4 */
 
+static struct nfs_open_dir_context *alloc_nfs_open_dir_context(struct rpc_cred *cred)
+{
+        struct nfs_open_dir_context *ctx;
+        ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
+        if (ctx != NULL) {
+                ctx->duped = 0;
+                ctx->dir_cookie = 0;
+                ctx->dup_cookie = 0;
+                ctx->cred = get_rpccred(cred);
+        } else
+                ctx = ERR_PTR(-ENOMEM);
+        return ctx;
+}
+
+static void put_nfs_open_dir_context(struct nfs_open_dir_context *ctx)
+{
+        put_rpccred(ctx->cred);
+        kfree(ctx);
+}
+
 /*
  * Open file
  */
 static int
 nfs_opendir(struct inode *inode, struct file *filp)
 {
-        int res;
+        int res = 0;
+        struct nfs_open_dir_context *ctx;
+        struct rpc_cred *cred;
 
         dfprintk(FILE, "NFS: open dir(%s/%s)\n",
                         filp->f_path.dentry->d_parent->d_name.name,
@@ -147,8 +170,15 @@ nfs_opendir(struct inode *inode, struct file *filp)
 
         nfs_inc_stats(inode, NFSIOS_VFSOPEN);
 
-        /* Call generic open code in order to cache credentials */
-        res = nfs_open(inode, filp);
+        cred = rpc_lookup_cred();
+        if (IS_ERR(cred))
+                return PTR_ERR(cred);
+        ctx = alloc_nfs_open_dir_context(cred);
+        if (IS_ERR(ctx)) {
+                res = PTR_ERR(ctx);
+                goto out;
+        }
+        filp->private_data = ctx;
         if (filp->f_path.dentry == filp->f_path.mnt->mnt_root) {
                 /* This is a mountpoint, so d_revalidate will never
                  * have been called, so we need to refresh the
@@ -156,9 +186,18 @@ nfs_opendir(struct inode *inode, struct file *filp)
                  */
                 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
         }
+out:
+        put_rpccred(cred);
         return res;
 }
 
+static int
+nfs_closedir(struct inode *inode, struct file *filp)
+{
+        put_nfs_open_dir_context(filp->private_data);
+        return 0;
+}
+
 struct nfs_cache_array_entry {
         u64 cookie;
         u64 ino;
@@ -284,19 +323,20 @@ int nfs_readdir_search_for_pos(struct nfs_cache_array *array, nfs_readdir_descri
 {
         loff_t diff = desc->file->f_pos - desc->current_index;
         unsigned int index;
+        struct nfs_open_dir_context *ctx = desc->file->private_data;
 
         if (diff < 0)
                 goto out_eof;
         if (diff >= array->size) {
                 if (array->eof_index >= 0)
                         goto out_eof;
-                desc->current_index += array->size;
                 return -EAGAIN;
         }
 
         index = (unsigned int)diff;
         *desc->dir_cookie = array->array[index].cookie;
         desc->cache_entry_index = index;
+        ctx->duped = 0;
         return 0;
 out_eof:
         desc->eof = 1;
@@ -307,10 +347,18 @@ static
 int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_descriptor_t *desc)
 {
         int i;
+        loff_t new_pos;
         int status = -EAGAIN;
+        struct nfs_open_dir_context *ctx = desc->file->private_data;
 
         for (i = 0; i < array->size; i++) {
                 if (array->array[i].cookie == *desc->dir_cookie) {
+                        new_pos = desc->current_index + i;
+                        if (new_pos < desc->file->f_pos) {
+                                ctx->dup_cookie = *desc->dir_cookie;
+                                ctx->duped = 1;
+                        }
+                        desc->file->f_pos = new_pos;
                         desc->cache_entry_index = i;
                         return 0;
                 }
@@ -342,6 +390,7 @@ int nfs_readdir_search_array(nfs_readdir_descriptor_t *desc)
 
         if (status == -EAGAIN) {
                 desc->last_cookie = array->last_cookie;
+                desc->current_index += array->size;
                 desc->page_index++;
         }
         nfs_readdir_release_array(desc->page);
@@ -354,7 +403,8 @@ static
 int nfs_readdir_xdr_filler(struct page **pages, nfs_readdir_descriptor_t *desc,
                         struct nfs_entry *entry, struct file *file, struct inode *inode)
 {
-        struct rpc_cred *cred = nfs_file_cred(file);
+        struct nfs_open_dir_context *ctx = file->private_data;
+        struct rpc_cred *cred = ctx->cred;
         unsigned long   timestamp, gencount;
         int             error;
 
@@ -693,6 +743,20 @@ int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
         int i = 0;
         int res = 0;
         struct nfs_cache_array *array = NULL;
+        struct nfs_open_dir_context *ctx = file->private_data;
+
+        if (ctx->duped != 0 && ctx->dup_cookie == *desc->dir_cookie) {
+                if (printk_ratelimit()) {
+                        pr_notice("NFS: directory %s/%s contains a readdir loop.  "
+                                "Please contact your server vendor.  "
+                                "Offending cookie: %llu\n",
+                                file->f_dentry->d_parent->d_name.name,
+                                file->f_dentry->d_name.name,
+                                *desc->dir_cookie);
+                }
+                res = -ELOOP;
+                goto out;
+        }
 
         array = nfs_readdir_get_array(desc->page);
         if (IS_ERR(array)) {
@@ -785,6 +849,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         struct inode    *inode = dentry->d_inode;
         nfs_readdir_descriptor_t my_desc,
                         *desc = &my_desc;
+        struct nfs_open_dir_context *dir_ctx = filp->private_data;
         int res;
 
         dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
@@ -801,7 +866,7 @@ static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         memset(desc, 0, sizeof(*desc));
 
         desc->file = filp;
-        desc->dir_cookie = &nfs_file_open_context(filp)->dir_cookie;
+        desc->dir_cookie = &dir_ctx->dir_cookie;
         desc->decode = NFS_PROTO(inode)->decode_dirent;
         desc->plus = NFS_USE_READDIRPLUS(inode);
 
@@ -853,6 +918,7 @@ static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
 {
         struct dentry *dentry = filp->f_path.dentry;
         struct inode *inode = dentry->d_inode;
+        struct nfs_open_dir_context *dir_ctx = filp->private_data;
 
         dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
                         dentry->d_parent->d_name.name,
@@ -872,7 +938,8 @@ static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
         }
         if (offset != filp->f_pos) {
                 filp->f_pos = offset;
-                nfs_file_open_context(filp)->dir_cookie = 0;
+                dir_ctx->dir_cookie = 0;
+                dir_ctx->duped = 0;
         }
 out:
         mutex_unlock(&inode->i_mutex);
@@ -1068,7 +1135,7 @@ static int nfs_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
         if (fhandle == NULL || fattr == NULL)
                 goto out_error;
 
-        error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
+        error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
         if (error)
                 goto out_bad;
         if (nfs_compare_fh(NFS_FH(inode), fhandle))
@@ -1169,11 +1236,23 @@ static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
         iput(inode);
 }
 
+static void nfs_d_release(struct dentry *dentry)
+{
+        /* free cached devname value, if it survived that far */
+        if (unlikely(dentry->d_fsdata)) {
+                if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
+                        WARN_ON(1);
+                else
+                        kfree(dentry->d_fsdata);
+        }
+}
+
 const struct dentry_operations nfs_dentry_operations = {
         .d_revalidate   = nfs_lookup_revalidate,
         .d_delete       = nfs_dentry_delete,
         .d_iput         = nfs_dentry_iput,
         .d_automount    = nfs_d_automount,
+        .d_release      = nfs_d_release,
 };
 
 static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
@@ -1212,7 +1291,7 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru
         parent = dentry->d_parent;
         /* Protect against concurrent sillydeletes */
         nfs_block_sillyrename(parent);
-        error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
+        error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
         if (error == -ENOENT)
                 goto no_entry;
         if (error < 0) {
@@ -1248,6 +1327,7 @@ const struct dentry_operations nfs4_dentry_operations = {
         .d_delete       = nfs_dentry_delete,
         .d_iput         = nfs_dentry_iput,
         .d_automount    = nfs_d_automount,
+        .d_release      = nfs_d_release,
 };
 
 /*
@@ -1549,7 +1629,7 @@ int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
         if (dentry->d_inode)
                 goto out;
         if (fhandle->size == 0) {
-                error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
+                error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
                 if (error)
                         goto out_error;
         }