NFS: Prevent integer overflow in nfs_scan_list()

Also ensure that nfs_inode ncommit and npages are large enough to represent
all possible values for the number of pages.

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

2 files changed, 3 insertions, 1 deletions

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index ad90cbe76703..68f6bf122006 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -425,6 +425,8 @@ int nfs_scan_list(struct nfs_inode *nfsi,
                                                 req->wb_index, tag);
                                 nfs_list_add_request(req, dst);
                                 res++;
+                                if (res == INT_MAX)
+                                        goto out;
                         }
                 }
 
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index a94205476736..750708ccd708 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -158,7 +158,7 @@ struct nfs_inode {
         spinlock_t              req_lock;
         struct radix_tree_root  nfs_page_tree;
 
-        unsigned int            ncommit,
+        unsigned long           ncommit,
                                 npages;
 
         /* Open contexts for shared mmap writes */