Merge branch 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

* 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: nfs_updatepage(): don't mark page as dirty if an error occurred
  NFS: Fix filehandle size comparisons in the mount code
  NFS: Reduce the NFS mount code stack usage.

3 files changed, 51 insertions, 37 deletions

diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c
index 49c7cd0502cc..779d2eb649c5 100644
--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -130,10 +130,11 @@ static int xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p,
                                 struct mnt_fhstatus *res)
 {
         struct nfs_fh *fh = res->fh;
+        unsigned size;
 
         if ((res->status = ntohl(*p++)) == 0) {
-                int size = ntohl(*p++);
-                if (size <= NFS3_FHSIZE) {
+                size = ntohl(*p++);
+                if (size <= NFS3_FHSIZE && size != 0) {
                         fh->size = size;
                         memcpy(fh->data, p, size);
                 } else
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 2a4a024a4e7b..614efeed5437 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1216,8 +1216,6 @@ static int nfs_validate_mount_data(void *options,
 {
         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
 
-        memset(args, 0, sizeof(*args));
-
         if (data == NULL)
                 goto out_no_data;
 
@@ -1251,13 +1249,13 @@ static int nfs_validate_mount_data(void *options,
         case 5:
                 memset(data->context, 0, sizeof(data->context));
         case 6:
-                if (data->flags & NFS_MOUNT_VER3)
+                if (data->flags & NFS_MOUNT_VER3) {
+                        if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
+                                goto out_invalid_fh;
                         mntfh->size = data->root.size;
-                else
+                } else
                         mntfh->size = NFS2_FHSIZE;
 
-                if (mntfh->size > sizeof(mntfh->data))
-                        goto out_invalid_fh;
 
                 memcpy(mntfh->data, data->root.data, mntfh->size);
                 if (mntfh->size < sizeof(mntfh->data))
@@ -1585,24 +1583,29 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 {
         struct nfs_server *server = NULL;
         struct super_block *s;
-        struct nfs_fh mntfh;
-        struct nfs_parsed_mount_data data;
+        struct nfs_parsed_mount_data *data;
+        struct nfs_fh *mntfh;
         struct dentry *mntroot;
         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
         struct nfs_sb_mountdata sb_mntdata = {
                 .mntflags = flags,
         };
-        int error;
+        int error = -ENOMEM;
+
+        data = kzalloc(sizeof(*data), GFP_KERNEL);
+        mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
+        if (data == NULL || mntfh == NULL)
+                goto out_free_fh;
 
-        security_init_mnt_opts(&data.lsm_opts);
+        security_init_mnt_opts(&data->lsm_opts);
 
         /* Validate the mount data */
-        error = nfs_validate_mount_data(raw_data, &data, &mntfh, dev_name);
+        error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
         if (error < 0)
                 goto out;
 
         /* Get a volume representation */
-        server = nfs_create_server(&data, &mntfh);
+        server = nfs_create_server(data, mntfh);
         if (IS_ERR(server)) {
                 error = PTR_ERR(server);
                 goto out;
@@ -1630,16 +1633,16 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 
         if (!s->s_root) {
                 /* initial superblock/root creation */
-                nfs_fill_super(s, &data);
+                nfs_fill_super(s, data);
         }
 
-        mntroot = nfs_get_root(s, &mntfh);
+        mntroot = nfs_get_root(s, mntfh);
         if (IS_ERR(mntroot)) {
                 error = PTR_ERR(mntroot);
                 goto error_splat_super;
         }
 
-        error = security_sb_set_mnt_opts(s, &data.lsm_opts);
+        error = security_sb_set_mnt_opts(s, &data->lsm_opts);
         if (error)
                 goto error_splat_root;
 
@@ -1649,9 +1652,12 @@ static int nfs_get_sb(struct file_system_type *fs_type,
         error = 0;
 
 out:
-        kfree(data.nfs_server.hostname);
-        kfree(data.mount_server.hostname);
-        security_free_mnt_opts(&data.lsm_opts);
+        kfree(data->nfs_server.hostname);
+        kfree(data->mount_server.hostname);
+        security_free_mnt_opts(&data->lsm_opts);
+out_free_fh:
+        kfree(mntfh);
+        kfree(data);
         return error;
 
 out_err_nosb:
@@ -1800,8 +1806,6 @@ static int nfs4_validate_mount_data(void *options,
         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
         char *c;
 
-        memset(args, 0, sizeof(*args));
-
         if (data == NULL)
                 goto out_no_data;
 
@@ -1959,26 +1963,31 @@ out_no_client_address:
 static int nfs4_get_sb(struct file_system_type *fs_type,
         int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
 {
-        struct nfs_parsed_mount_data data;
+        struct nfs_parsed_mount_data *data;
         struct super_block *s;
         struct nfs_server *server;
-        struct nfs_fh mntfh;
+        struct nfs_fh *mntfh;
         struct dentry *mntroot;
         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
         struct nfs_sb_mountdata sb_mntdata = {
                 .mntflags = flags,
         };
-        int error;
+        int error = -ENOMEM;
 
-        security_init_mnt_opts(&data.lsm_opts);
+        data = kzalloc(sizeof(*data), GFP_KERNEL);
+        mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
+        if (data == NULL || mntfh == NULL)
+                goto out_free_fh;
+
+        security_init_mnt_opts(&data->lsm_opts);
 
         /* Validate the mount data */
-        error = nfs4_validate_mount_data(raw_data, &data, dev_name);
+        error = nfs4_validate_mount_data(raw_data, data, dev_name);
         if (error < 0)
                 goto out;
 
         /* Get a volume representation */
-        server = nfs4_create_server(&data, &mntfh);
+        server = nfs4_create_server(data, mntfh);
         if (IS_ERR(server)) {
                 error = PTR_ERR(server);
                 goto out;
@@ -2009,13 +2018,13 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
                 nfs4_fill_super(s);
         }
 
-        mntroot = nfs4_get_root(s, &mntfh);
+        mntroot = nfs4_get_root(s, mntfh);
         if (IS_ERR(mntroot)) {
                 error = PTR_ERR(mntroot);
                 goto error_splat_super;
         }
 
-        error = security_sb_set_mnt_opts(s, &data.lsm_opts);
+        error = security_sb_set_mnt_opts(s, &data->lsm_opts);
         if (error)
                 goto error_splat_root;
 
@@ -2025,10 +2034,13 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
         error = 0;
 
 out:
-        kfree(data.client_address);
-        kfree(data.nfs_server.export_path);
-        kfree(data.nfs_server.hostname);
-        security_free_mnt_opts(&data.lsm_opts);
+        kfree(data->client_address);
+        kfree(data->nfs_server.export_path);
+        kfree(data->nfs_server.hostname);
+        security_free_mnt_opts(&data->lsm_opts);
+out_free_fh:
+        kfree(mntfh);
+        kfree(data);
         return error;
 
 out_free:
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 6d8ace3e3259..f333848fd3be 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -739,12 +739,13 @@ int nfs_updatepage(struct file *file, struct page *page,
         }
 
         status = nfs_writepage_setup(ctx, page, offset, count);
-        __set_page_dirty_nobuffers(page);
+        if (status < 0)
+                nfs_set_pageerror(page);
+        else
+                __set_page_dirty_nobuffers(page);
 
         dprintk("NFS:      nfs_updatepage returns %d (isize %Ld)\n",
                         status, (long long)i_size_read(inode));
-        if (status < 0)
-                nfs_set_pageerror(page);
         return status;
 }