From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751249AbXITTzh (ORCPT ); Thu, 20 Sep 2007 15:55:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752137AbXITTxL (ORCPT ); Thu, 20 Sep 2007 15:53:11 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.143]:55522 "EHLO e3.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751938AbXITTxG (ORCPT ); Thu, 20 Sep 2007 15:53:06 -0400 Subject: [PATCH 11/25] elevate write count during entire ncp_ioctl() To: akpm@osdl.org Cc: linux-kernel@vger.kernel.org, hch@infradead.org, Dave Hansen From: Dave Hansen Date: Thu, 20 Sep 2007 12:53:02 -0700 References: <20070920195249.852667D5@kernel> In-Reply-To: <20070920195249.852667D5@kernel> Message-Id: <20070920195302.ACDE8A3E@kernel> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Some ioctls need write access, but others don't. Make a helper function to decide when write access is needed, and take it. Signed-off-by: Dave Hansen --- lxc-dave/fs/ncpfs/ioctl.c | 54 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 53 insertions(+), 1 deletion(-) diff -puN fs/ncpfs/ioctl.c~elevate-write-count-during-entire-ncp-ioctl fs/ncpfs/ioctl.c --- lxc/fs/ncpfs/ioctl.c~elevate-write-count-during-entire-ncp-ioctl 2007-09-20 12:16:15.000000000 -0700 +++ lxc-dave/fs/ncpfs/ioctl.c 2007-09-20 12:16:15.000000000 -0700 @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -261,7 +262,7 @@ ncp_get_charsets(struct ncp_server* serv } #endif /* CONFIG_NCPFS_NLS */ -int ncp_ioctl(struct inode *inode, struct file *filp, +static int __ncp_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) { struct ncp_server *server = NCP_SERVER(inode); @@ -822,6 +823,57 @@ outrel: return -EINVAL; } +static int ncp_ioctl_need_write(unsigned int cmd) +{ + switch (cmd) { + case NCP_IOC_GET_FS_INFO: + case NCP_IOC_GET_FS_INFO_V2: + case NCP_IOC_NCPREQUEST: + case NCP_IOC_SETDENTRYTTL: + case NCP_IOC_SIGN_INIT: + case NCP_IOC_LOCKUNLOCK: + case NCP_IOC_SET_SIGN_WANTED: + return 1; + case NCP_IOC_GETOBJECTNAME: + case NCP_IOC_SETOBJECTNAME: + case NCP_IOC_GETPRIVATEDATA: + case NCP_IOC_SETPRIVATEDATA: + case NCP_IOC_SETCHARSETS: + case NCP_IOC_GETCHARSETS: + case NCP_IOC_CONN_LOGGED_IN: + case NCP_IOC_GETDENTRYTTL: + case NCP_IOC_GETMOUNTUID2: + case NCP_IOC_SIGN_WANTED: + case NCP_IOC_GETROOT: + case NCP_IOC_SETROOT: + return 0; + default: + /* unkown IOCTL command, assume write */ + } + return 1; +} + +int ncp_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + int ret; + + if (ncp_ioctl_need_write(cmd)) { + /* + * inside the ioctl(), any failures which + * are because of file_permission() are + * -EACCESS, so it seems consistent to keep + * that here. + */ + if (mnt_want_write(filp->f_vfsmnt)) + return -EACCES; + } + ret = __ncp_ioctl(inode, filp, cmd, arg); + if (ncp_ioctl_need_write(cmd)) + mnt_drop_write(filp->f_vfsmnt); + return ret; +} + #ifdef CONFIG_COMPAT long ncp_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { _