Commit 65e4308d authored by Trond Myklebust's avatar Trond Myklebust Committed by Linus Torvalds
Browse files

[PATCH] NFS: Ensure we always update inode->i_mode when doing O_EXCL creates 

When the client performs an exclusive create and opens the file for writing,
a Netapp filer will first create the file using the mode 01777. It does this
since an NFSv3/v4 exclusive create cannot immediately set the mode bits.
The 01777 mode then gets put into the inode->i_mode. After the file creation
is successful, we then do a setattr to change the mode to the correct value
(as per the NFS spec).

The problem is that nfs_refresh_inode() no longer updates inode->i_mode, so
the latter retains the 01777 mode. A bit later, the VFS notices this, and calls
remove_suid(). This of course now resets the file mode to inode->i_mode & 0777.
Hey presto, the file mode on the server is now magically changed to 0777. Duh...

Fixes http://bugzilla.linux-nfs.org/show_bug.cgi?id=32



Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 367ae3cd

fs/nfs/inode.c

+24 −13
Original line number Diff line number Diff line
@@ -814,29 +814,40 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr) 
		nfs_wb_all(inode);

	}

	error = NFS_PROTO(inode)->setattr(dentry, &fattr, attr);

	if (error == 0) {

	if (error == 0)

		nfs_refresh_inode(inode, &fattr);

	nfs_end_data_update(inode);

	unlock_kernel();

	return error;

}



/**

 * nfs_setattr_update_inode - Update inode metadata after a setattr call.

 * @inode: pointer to struct inode

 * @attr: pointer to struct iattr

 *

 * Note: we do this in the *proc.c in order to ensure that

 *       it works for things like exclusive creates too.

 */

void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)

{

	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {

		if ((attr->ia_valid & ATTR_MODE) != 0) {

			int mode;

			mode = inode->i_mode & ~S_IALLUGO;

			mode |= attr->ia_mode & S_IALLUGO;

			int mode = attr->ia_mode & S_IALLUGO;

			mode |= inode->i_mode & ~S_IALLUGO;

			inode->i_mode = mode;

		}

		if ((attr->ia_valid & ATTR_UID) != 0)

			inode->i_uid = attr->ia_uid;

		if ((attr->ia_valid & ATTR_GID) != 0)

			inode->i_gid = attr->ia_gid;

		NFS_FLAGS(inode) |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;

	}

	if ((attr->ia_valid & ATTR_SIZE) != 0) {

		inode->i_size = attr->ia_size;

		vmtruncate(inode, attr->ia_size);

	}

}

	if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)

		NFS_FLAGS(inode) |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;

	nfs_end_data_update(inode);

	unlock_kernel();

	return error;

}



/*

 * Wait for the inode to get unlocked.

fs/nfs/nfs3proc.c

+4 −0
Original line number Diff line number Diff line
@@ -120,6 +120,8 @@ nfs3_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, 
	dprintk("NFS call  setattr\n");

	fattr->valid = 0;

	status = rpc_call(NFS_CLIENT(inode), NFS3PROC_SETATTR, &arg, fattr, 0);

	if (status == 0)

		nfs_setattr_update_inode(inode, sattr);

	dprintk("NFS reply setattr: %d\n", status);

	return status;

}
@@ -370,6 +372,8 @@ again: 
		 * not sure this buys us anything (and I'd have

		 * to revamp the NFSv3 XDR code) */

		status = nfs3_proc_setattr(dentry, &fattr, sattr);

		if (status == 0)

			nfs_setattr_update_inode(dentry->d_inode, sattr);

		nfs_refresh_inode(dentry->d_inode, &fattr);

		dprintk("NFS reply setattr (post-create): %d\n", status);

	}

fs/nfs/nfs4proc.c

+8 −2
Original line number Diff line number Diff line
@@ -753,6 +753,7 @@ static int _nfs4_do_setattr(struct nfs_server *server, struct nfs_fattr *fattr, 
                .rpc_argp       = &arg,

                .rpc_resp       = &res,

        };

	int status;



        fattr->valid = 0;
@@ -762,7 +763,8 @@ static int _nfs4_do_setattr(struct nfs_server *server, struct nfs_fattr *fattr, 
	} else

		memcpy(&arg.stateid, &zero_stateid, sizeof(arg.stateid));



	return rpc_call_sync(server->client, &msg, 0);

	status = rpc_call_sync(server->client, &msg, 0);

	return status;

}



static int nfs4_do_setattr(struct nfs_server *server, struct nfs_fattr *fattr,
@@ -1145,6 +1147,8 @@ nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, 


	status = nfs4_do_setattr(NFS_SERVER(inode), fattr,

			NFS_FH(inode), sattr, state);

	if (status == 0)

		nfs_setattr_update_inode(inode, sattr);

	if (state != NULL)

		nfs4_close_state(state, FMODE_WRITE);

	put_rpccred(cred);
@@ -1449,8 +1453,10 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr, 
		struct nfs_fattr fattr;

		status = nfs4_do_setattr(NFS_SERVER(dir), &fattr,

		                     NFS_FH(state->inode), sattr, state);

		if (status == 0)

		if (status == 0) {

			nfs_setattr_update_inode(state->inode, sattr);

			goto out;

		}

	} else if (flags != 0)

		goto out;

	nfs4_close_state(state, flags);

fs/nfs/proc.c

+2 −0
Original line number Diff line number Diff line
@@ -114,6 +114,8 @@ nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, 
	dprintk("NFS call  setattr\n");

	fattr->valid = 0;

	status = rpc_call(NFS_CLIENT(inode), NFSPROC_SETATTR, &arg, fattr, 0);

	if (status == 0)

		nfs_setattr_update_inode(inode, sattr);

	dprintk("NFS reply setattr: %d\n", status);

	return status;

}

include/linux/nfs_fs.h

+1 −0
Original line number Diff line number Diff line
@@ -292,6 +292,7 @@ extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode); 
extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);

extern void nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);

extern int nfs_setattr(struct dentry *, struct iattr *);

extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);

extern void nfs_begin_attr_update(struct inode *);

extern void nfs_end_attr_update(struct inode *);

extern void nfs_begin_data_update(struct inode *);

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