NFS: Fix a buffer overflow in the allocation of struct nfs_read/writedata
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index f001606..9a55807 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -27,8 +27,8 @@
#define NFSDBG_FACILITY NFSDBG_PAGECACHE
-static int nfs_pagein_multi(struct inode *, struct list_head *, size_t, int);
-static int nfs_pagein_one(struct inode *, struct list_head *, size_t, int);
+static int nfs_pagein_multi(struct inode *, struct list_head *, unsigned int, size_t, int);
+static int nfs_pagein_one(struct inode *, struct list_head *, unsigned int, size_t, int);
static const struct rpc_call_ops nfs_read_partial_ops;
static const struct rpc_call_ops nfs_read_full_ops;
@@ -37,9 +37,8 @@
#define MIN_POOL_READ (32)
-struct nfs_read_data *nfs_readdata_alloc(size_t len)
+struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount)
{
- unsigned int pagecount = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
struct nfs_read_data *p = mempool_alloc(nfs_rdata_mempool, GFP_NOFS);
if (p) {
@@ -135,9 +134,9 @@
nfs_list_add_request(new, &one_request);
if (NFS_SERVER(inode)->rsize < PAGE_CACHE_SIZE)
- nfs_pagein_multi(inode, &one_request, len, 0);
+ nfs_pagein_multi(inode, &one_request, 1, len, 0);
else
- nfs_pagein_one(inode, &one_request, len, 0);
+ nfs_pagein_one(inode, &one_request, 1, len, 0);
return 0;
}
@@ -234,7 +233,7 @@
* won't see the new data until our attribute cache is updated. This is more
* or less conventional NFS client behavior.
*/
-static int nfs_pagein_multi(struct inode *inode, struct list_head *head, size_t count, int flags)
+static int nfs_pagein_multi(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int flags)
{
struct nfs_page *req = nfs_list_entry(head->next);
struct page *page = req->wb_page;
@@ -250,7 +249,7 @@
do {
size_t len = min(nbytes,rsize);
- data = nfs_readdata_alloc(len);
+ data = nfs_readdata_alloc(1);
if (!data)
goto out_bad;
INIT_LIST_HEAD(&data->pages);
@@ -291,13 +290,13 @@
return -ENOMEM;
}
-static int nfs_pagein_one(struct inode *inode, struct list_head *head, size_t count, int flags)
+static int nfs_pagein_one(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int flags)
{
struct nfs_page *req;
struct page **pages;
struct nfs_read_data *data;
- data = nfs_readdata_alloc(count);
+ data = nfs_readdata_alloc(npages);
if (!data)
goto out_bad;