[PATCH] NFS: fix error handling on access_ok in compat_sys_nfsservctl
Functions compat_nfs_svc_trans, compat_nfs_clnt_trans,
compat_nfs_exp_trans, compat_nfs_getfd_trans and compat_nfs_getfs_trans,
which are called by compat_sys_nfsservctl(fs/compat.c), don't handle the
return value of access_ok properly. access_ok return 1 when the addr is
valid, and 0 when it's not, but these functions have the reversed
understanding. When the address is valid, they always return -EFAULT to
compat_sys_nfsservctl.
An example is to run /usr/sbin/rpc.nfsd(32bit program on Power5). It
doesn't function as expected. strace showes that nfsservctl returns
-EFAULT.
The patch fixes this by correcting the error handling on the return value
of access_ok in the five functions.
Signed-off-by: Lin Feng Shen <shenlinf@cn.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/compat.c b/fs/compat.c
index 01f39f8..b1f6478 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -2030,109 +2030,115 @@
struct knfsd_fh cr32_getfs;
};
-static int compat_nfs_svc_trans(struct nfsctl_arg *karg, struct compat_nfsctl_arg __user *arg)
+static int compat_nfs_svc_trans(struct nfsctl_arg *karg,
+ struct compat_nfsctl_arg __user *arg)
{
- int err;
-
- err = access_ok(VERIFY_READ, &arg->ca32_svc, sizeof(arg->ca32_svc));
- err |= get_user(karg->ca_version, &arg->ca32_version);
- err |= __get_user(karg->ca_svc.svc_port, &arg->ca32_svc.svc32_port);
- err |= __get_user(karg->ca_svc.svc_nthreads, &arg->ca32_svc.svc32_nthreads);
- return (err) ? -EFAULT : 0;
+ if (!access_ok(VERIFY_READ, &arg->ca32_svc, sizeof(arg->ca32_svc)) ||
+ get_user(karg->ca_version, &arg->ca32_version) ||
+ __get_user(karg->ca_svc.svc_port, &arg->ca32_svc.svc32_port) ||
+ __get_user(karg->ca_svc.svc_nthreads,
+ &arg->ca32_svc.svc32_nthreads))
+ return -EFAULT;
+ return 0;
}
-static int compat_nfs_clnt_trans(struct nfsctl_arg *karg, struct compat_nfsctl_arg __user *arg)
+static int compat_nfs_clnt_trans(struct nfsctl_arg *karg,
+ struct compat_nfsctl_arg __user *arg)
{
- int err;
+ if (!access_ok(VERIFY_READ, &arg->ca32_client,
+ sizeof(arg->ca32_client)) ||
+ get_user(karg->ca_version, &arg->ca32_version) ||
+ __copy_from_user(&karg->ca_client.cl_ident[0],
+ &arg->ca32_client.cl32_ident[0],
+ NFSCLNT_IDMAX) ||
+ __get_user(karg->ca_client.cl_naddr,
+ &arg->ca32_client.cl32_naddr) ||
+ __copy_from_user(&karg->ca_client.cl_addrlist[0],
+ &arg->ca32_client.cl32_addrlist[0],
+ (sizeof(struct in_addr) * NFSCLNT_ADDRMAX)) ||
+ __get_user(karg->ca_client.cl_fhkeytype,
+ &arg->ca32_client.cl32_fhkeytype) ||
+ __get_user(karg->ca_client.cl_fhkeylen,
+ &arg->ca32_client.cl32_fhkeylen) ||
+ __copy_from_user(&karg->ca_client.cl_fhkey[0],
+ &arg->ca32_client.cl32_fhkey[0],
+ NFSCLNT_KEYMAX))
+ return -EFAULT;
- err = access_ok(VERIFY_READ, &arg->ca32_client, sizeof(arg->ca32_client));
- err |= get_user(karg->ca_version, &arg->ca32_version);
- err |= __copy_from_user(&karg->ca_client.cl_ident[0],
- &arg->ca32_client.cl32_ident[0],
- NFSCLNT_IDMAX);
- err |= __get_user(karg->ca_client.cl_naddr, &arg->ca32_client.cl32_naddr);
- err |= __copy_from_user(&karg->ca_client.cl_addrlist[0],
- &arg->ca32_client.cl32_addrlist[0],
- (sizeof(struct in_addr) * NFSCLNT_ADDRMAX));
- err |= __get_user(karg->ca_client.cl_fhkeytype,
- &arg->ca32_client.cl32_fhkeytype);
- err |= __get_user(karg->ca_client.cl_fhkeylen,
- &arg->ca32_client.cl32_fhkeylen);
- err |= __copy_from_user(&karg->ca_client.cl_fhkey[0],
- &arg->ca32_client.cl32_fhkey[0],
- NFSCLNT_KEYMAX);
-
- return (err) ? -EFAULT : 0;
+ return 0;
}
-static int compat_nfs_exp_trans(struct nfsctl_arg *karg, struct compat_nfsctl_arg __user *arg)
+static int compat_nfs_exp_trans(struct nfsctl_arg *karg,
+ struct compat_nfsctl_arg __user *arg)
{
- int err;
-
- err = access_ok(VERIFY_READ, &arg->ca32_export, sizeof(arg->ca32_export));
- err |= get_user(karg->ca_version, &arg->ca32_version);
- err |= __copy_from_user(&karg->ca_export.ex_client[0],
- &arg->ca32_export.ex32_client[0],
- NFSCLNT_IDMAX);
- err |= __copy_from_user(&karg->ca_export.ex_path[0],
- &arg->ca32_export.ex32_path[0],
- NFS_MAXPATHLEN);
- err |= __get_user(karg->ca_export.ex_dev,
- &arg->ca32_export.ex32_dev);
- err |= __get_user(karg->ca_export.ex_ino,
- &arg->ca32_export.ex32_ino);
- err |= __get_user(karg->ca_export.ex_flags,
- &arg->ca32_export.ex32_flags);
- err |= __get_user(karg->ca_export.ex_anon_uid,
- &arg->ca32_export.ex32_anon_uid);
- err |= __get_user(karg->ca_export.ex_anon_gid,
- &arg->ca32_export.ex32_anon_gid);
+ if (!access_ok(VERIFY_READ, &arg->ca32_export,
+ sizeof(arg->ca32_export)) ||
+ get_user(karg->ca_version, &arg->ca32_version) ||
+ __copy_from_user(&karg->ca_export.ex_client[0],
+ &arg->ca32_export.ex32_client[0],
+ NFSCLNT_IDMAX) ||
+ __copy_from_user(&karg->ca_export.ex_path[0],
+ &arg->ca32_export.ex32_path[0],
+ NFS_MAXPATHLEN) ||
+ __get_user(karg->ca_export.ex_dev,
+ &arg->ca32_export.ex32_dev) ||
+ __get_user(karg->ca_export.ex_ino,
+ &arg->ca32_export.ex32_ino) ||
+ __get_user(karg->ca_export.ex_flags,
+ &arg->ca32_export.ex32_flags) ||
+ __get_user(karg->ca_export.ex_anon_uid,
+ &arg->ca32_export.ex32_anon_uid) ||
+ __get_user(karg->ca_export.ex_anon_gid,
+ &arg->ca32_export.ex32_anon_gid))
+ return -EFAULT;
SET_UID(karg->ca_export.ex_anon_uid, karg->ca_export.ex_anon_uid);
SET_GID(karg->ca_export.ex_anon_gid, karg->ca_export.ex_anon_gid);
- return (err) ? -EFAULT : 0;
+ return 0;
}
-static int compat_nfs_getfd_trans(struct nfsctl_arg *karg, struct compat_nfsctl_arg __user *arg)
+static int compat_nfs_getfd_trans(struct nfsctl_arg *karg,
+ struct compat_nfsctl_arg __user *arg)
{
- int err;
+ if (!access_ok(VERIFY_READ, &arg->ca32_getfd,
+ sizeof(arg->ca32_getfd)) ||
+ get_user(karg->ca_version, &arg->ca32_version) ||
+ __copy_from_user(&karg->ca_getfd.gd_addr,
+ &arg->ca32_getfd.gd32_addr,
+ (sizeof(struct sockaddr))) ||
+ __copy_from_user(&karg->ca_getfd.gd_path,
+ &arg->ca32_getfd.gd32_path,
+ (NFS_MAXPATHLEN+1)) ||
+ __get_user(karg->ca_getfd.gd_version,
+ &arg->ca32_getfd.gd32_version))
+ return -EFAULT;
- err = access_ok(VERIFY_READ, &arg->ca32_getfd, sizeof(arg->ca32_getfd));
- err |= get_user(karg->ca_version, &arg->ca32_version);
- err |= __copy_from_user(&karg->ca_getfd.gd_addr,
- &arg->ca32_getfd.gd32_addr,
- (sizeof(struct sockaddr)));
- err |= __copy_from_user(&karg->ca_getfd.gd_path,
- &arg->ca32_getfd.gd32_path,
- (NFS_MAXPATHLEN+1));
- err |= __get_user(karg->ca_getfd.gd_version,
- &arg->ca32_getfd.gd32_version);
-
- return (err) ? -EFAULT : 0;
+ return 0;
}
-static int compat_nfs_getfs_trans(struct nfsctl_arg *karg, struct compat_nfsctl_arg __user *arg)
+static int compat_nfs_getfs_trans(struct nfsctl_arg *karg,
+ struct compat_nfsctl_arg __user *arg)
{
- int err;
+ if (!access_ok(VERIFY_READ,&arg->ca32_getfs,sizeof(arg->ca32_getfs)) ||
+ get_user(karg->ca_version, &arg->ca32_version) ||
+ __copy_from_user(&karg->ca_getfs.gd_addr,
+ &arg->ca32_getfs.gd32_addr,
+ (sizeof(struct sockaddr))) ||
+ __copy_from_user(&karg->ca_getfs.gd_path,
+ &arg->ca32_getfs.gd32_path,
+ (NFS_MAXPATHLEN+1)) ||
+ __get_user(karg->ca_getfs.gd_maxlen,
+ &arg->ca32_getfs.gd32_maxlen))
+ return -EFAULT;
- err = access_ok(VERIFY_READ, &arg->ca32_getfs, sizeof(arg->ca32_getfs));
- err |= get_user(karg->ca_version, &arg->ca32_version);
- err |= __copy_from_user(&karg->ca_getfs.gd_addr,
- &arg->ca32_getfs.gd32_addr,
- (sizeof(struct sockaddr)));
- err |= __copy_from_user(&karg->ca_getfs.gd_path,
- &arg->ca32_getfs.gd32_path,
- (NFS_MAXPATHLEN+1));
- err |= __get_user(karg->ca_getfs.gd_maxlen,
- &arg->ca32_getfs.gd32_maxlen);
-
- return (err) ? -EFAULT : 0;
+ return 0;
}
/* This really doesn't need translations, we are only passing
* back a union which contains opaque nfs file handle data.
*/
-static int compat_nfs_getfh_res_trans(union nfsctl_res *kres, union compat_nfsctl_res __user *res)
+static int compat_nfs_getfh_res_trans(union nfsctl_res *kres,
+ union compat_nfsctl_res __user *res)
{
int err;
@@ -2141,8 +2147,9 @@
return (err) ? -EFAULT : 0;
}
-asmlinkage long compat_sys_nfsservctl(int cmd, struct compat_nfsctl_arg __user *arg,
- union compat_nfsctl_res __user *res)
+asmlinkage long compat_sys_nfsservctl(int cmd,
+ struct compat_nfsctl_arg __user *arg,
+ union compat_nfsctl_res __user *res)
{
struct nfsctl_arg *karg;
union nfsctl_res *kres;