From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Subject: [RFC][PATCH 05/20] elevate write count during entire ncp_ioctl() Date: Fri, 16 Jun 2006 16:12:17 -0700 Message-ID: <20060616231217.9D5B7848@localhost.localdomain> References: <20060616231213.D4C5D6AF@localhost.localdomain> Cc: linux-fsdevel@vger.kernel.org, herbert@13thfloor.at, viro@ftp.linux.org.uk, Dave Hansen Return-path: Received: from e1.ny.us.ibm.com ([32.97.182.141]:13476 "EHLO e1.ny.us.ibm.com") by vger.kernel.org with ESMTP id S1751549AbWFPXMW (ORCPT ); Fri, 16 Jun 2006 19:12:22 -0400 To: linux-kernel@vger.kernel.org In-Reply-To: <20060616231213.D4C5D6AF@localhost.localdomain> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.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 | 55 +++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 54 insertions(+), 1 deletion(-) diff -puN fs/ncpfs/ioctl.c~C-elevate-writers-file_permission-callers fs/ncpfs/ioctl.c --- lxc/fs/ncpfs/ioctl.c~C-elevate-writers-file_permission-callers 2006-06-16 15:58:02.000000000 -0700 +++ lxc-dave/fs/ncpfs/ioctl.c 2006-06-16 15:58:02.000000000 -0700 @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -183,7 +184,7 @@ 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); @@ -654,3 +655,55 @@ outrel: /* #endif */ 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 */ + WARN_ON(1); + } + 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; +} _