The following patch fixes an issue relating to remount and argument
parsing. After this fix is applied, remount becomes atomic in that
it either succeeds changing the mount to the new state, or it fails
and leaves it in the old state. Previously it was possible for the
parsing of options to fail part way though and for the fs to be left
in a state where some of the new arguments had been applied, but some
had not.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
/* Split the options into tokens with the "," character and
process them */
- for (options = data; (o = strsep(&options, ",")); ) {
- int token;
- substring_t tmp[MAX_OPT_ARGS];
-
- if (!*o)
+ while (1) {
+ o = strsep(&options, ",");
+ if (o == NULL)
+ break;
+ if (*o == ' ')
continue;
token = match_token(o, tokens, tmp);
switch (token) {
case Opt_lockproto:
- v = match_strdup(&tmp[0]);
- if (!v) {
- fs_info(sdp, "no memory for lockproto
");
- error = -ENOMEM;
- goto out_error;
- }
-
- if (remount && strcmp(v, args->ar_lockproto)) {
- kfree(v);
- goto cant_remount;
- }
-
- strncpy(args->ar_lockproto, v, GFS2_LOCKNAME_LEN);
- args->ar_lockproto[GFS2_LOCKNAME_LEN - 1] = 0;
- kfree(v);
+ match_strlcpy(args->ar_lockproto, &tmp[0],
+ GFS2_LOCKNAME_LEN);
break;
case Opt_locktable:
- v = match_strdup(&tmp[0]);
- if (!v) {
- fs_info(sdp, "no memory for locktable
");
- error = -ENOMEM;
- goto out_error;
- }
-
- if (remount && strcmp(v, args->ar_locktable)) {
- kfree(v);
- goto cant_remount;
- }
-
- strncpy(args->ar_locktable, v, GFS2_LOCKNAME_LEN);
- args->ar_locktable[GFS2_LOCKNAME_LEN - 1] = 0;
- kfree(v);
+ match_strlcpy(args->ar_locktable, &tmp[0],
+ GFS2_LOCKNAME_LEN);
break;
case Opt_hostdata:
- v = match_strdup(&tmp[0]);
- if (!v) {
- fs_info(sdp, "no memory for hostdata
");
- error = -ENOMEM;
- goto out_error;
- }
-
- if (remount && strcmp(v, args->ar_hostdata)) {
- kfree(v);
- goto cant_remount;
- }
-
- strncpy(args->ar_hostdata, v, GFS2_LOCKNAME_LEN);
- args->ar_hostdata[GFS2_LOCKNAME_LEN - 1] = 0;
- kfree(v);
+ match_strlcpy(args->ar_hostdata, &tmp[0],
+ GFS2_LOCKNAME_LEN);
break;
case Opt_spectator:
- if (remount && !args->ar_spectator)
- goto cant_remount;
args->ar_spectator = 1;
- sdp->sd_vfs->s_flags |= MS_RDONLY;
break;
case Opt_ignore_local_fs:
- if (remount && !args->ar_ignore_local_fs)
- goto cant_remount;
args->ar_ignore_local_fs = 1;
break;
case Opt_localflocks:
- if (remount && !args->ar_localflocks)
- goto cant_remount;
args->ar_localflocks = 1;
break;
case Opt_localcaching:
- if (remount && !args->ar_localcaching)
- goto cant_remount;
args->ar_localcaching = 1;
break;
case Opt_debug:
@@ -181,17 +126,13 @@ int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount)
args->ar_debug = 0;
break;
case Opt_upgrade:
- if (remount && !args->ar_upgrade)
- goto cant_remount;
args->ar_upgrade = 1;
break;
case Opt_acl:
args->ar_posix_acl = 1;
- sdp->sd_vfs->s_flags |= MS_POSIXACL;
break;
case Opt_noacl:
args->ar_posix_acl = 0;
- sdp->sd_vfs->s_flags &= ~MS_POSIXACL;
break;
case Opt_quota_off:
args->ar_quota = GFS2_QUOTA_OFF;
@@ -215,29 +156,15 @@ int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount)
args->ar_data = GFS2_DATA_ORDERED;
break;
case Opt_meta:
- if (remount && args->ar_meta != 1)
- goto cant_remount;
args->ar_meta = 1;
break;
case Opt_err:
default:
- fs_info(sdp, "unknown option: %s
", o);
- error = -EINVAL;
- goto out_error;
+ fs_info(sdp, "invalid mount option: %s
", o);
+ return -EINVAL;
}
}
-out_error:
- if (error)
- fs_info(sdp, "invalid mount option(s)
");
-
- if (data != data_arg)
- kfree(data);
-
- return error;
-
-cant_remount:
- fs_info(sdp, "can't remount with option %s
", o);
- return -EINVAL;
+ return 0;
}
diff --git a/fs/gfs2/mount.h b/fs/gfs2/mount.h
deleted file mode 100644
index 401288a..0000000
--- a/fs/gfs2/mount.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/*
- * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
- * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
- *
- * This copyrighted material is made available to anyone wishing to use,
- * modify, copy, or redistribute it subject to the terms and conditions
- * of the GNU General Public License version 2.
- */
-
-#ifndef __MOUNT_DOT_H__
-#define __MOUNT_DOT_H__
-
-struct gfs2_sbd;
-
-int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount);
-
-#endif /* __MOUNT_DOT_H__ */
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index f91eebd..3eb49ed 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -25,7 +25,6 @@
#include "glock.h"
#include "glops.h"
#include "inode.h"
-#include "mount.h"
#include "recovery.h"
#include "rgrp.h"
#include "super.h"
@@ -1116,12 +1115,20 @@ static int fill_super(struct super_block *sb, void *data, int silent)
return -ENOMEM;
}
The following patch fixes an issue relating to remount and argument
parsing. After this fix is applied, remount becomes atomic in that
it either succeeds changing the mount to the new state, or it fails
and leaves it in the old state. Previously it was possible for the
parsing of options to fail part way though and for the fs to be left
in a state where some of the new arguments had been applied, but some
had not.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
/* Split the options into tokens with the "," character and
process them */
- for (options = data; (o = strsep(&options, ",")); ) {
- int token;
- substring_t tmp[MAX_OPT_ARGS];
-
- if (!*o)
+ while (1) {
+ o = strsep(&options, ",");
+ if (o == NULL)
+ break;
+ if (*o == ' ')
continue;
token = match_token(o, tokens, tmp);
switch (token) {
case Opt_lockproto:
- v = match_strdup(&tmp[0]);
- if (!v) {
- fs_info(sdp, "no memory for lockproto
");
- error = -ENOMEM;
- goto out_error;
- }
-
- if (remount && strcmp(v, args->ar_lockproto)) {
- kfree(v);
- goto cant_remount;
- }
-
- strncpy(args->ar_lockproto, v, GFS2_LOCKNAME_LEN);
- args->ar_lockproto[GFS2_LOCKNAME_LEN - 1] = 0;
- kfree(v);
+ match_strlcpy(args->ar_lockproto, &tmp[0],
+ GFS2_LOCKNAME_LEN);
break;
case Opt_locktable:
- v = match_strdup(&tmp[0]);
- if (!v) {
- fs_info(sdp, "no memory for locktable
");
- error = -ENOMEM;
- goto out_error;
- }
-
- if (remount && strcmp(v, args->ar_locktable)) {
- kfree(v);
- goto cant_remount;
- }
-
- strncpy(args->ar_locktable, v, GFS2_LOCKNAME_LEN);
- args->ar_locktable[GFS2_LOCKNAME_LEN - 1] = 0;
- kfree(v);
+ match_strlcpy(args->ar_locktable, &tmp[0],
+ GFS2_LOCKNAME_LEN);
break;
case Opt_hostdata:
- v = match_strdup(&tmp[0]);
- if (!v) {
- fs_info(sdp, "no memory for hostdata
");
- error = -ENOMEM;
- goto out_error;
- }
-
- if (remount && strcmp(v, args->ar_hostdata)) {
- kfree(v);
- goto cant_remount;
- }
-
- strncpy(args->ar_hostdata, v, GFS2_LOCKNAME_LEN);
- args->ar_hostdata[GFS2_LOCKNAME_LEN - 1] = 0;
- kfree(v);
+ match_strlcpy(args->ar_hostdata, &tmp[0],
+ GFS2_LOCKNAME_LEN);
break;
case Opt_spectator:
- if (remount && !args->ar_spectator)
- goto cant_remount;
args->ar_spectator = 1;
- sdp->sd_vfs->s_flags |= MS_RDONLY;
break;
case Opt_ignore_local_fs:
- if (remount && !args->ar_ignore_local_fs)
- goto cant_remount;
args->ar_ignore_local_fs = 1;
break;
case Opt_localflocks:
- if (remount && !args->ar_localflocks)
- goto cant_remount;
args->ar_localflocks = 1;
break;
case Opt_localcaching:
- if (remount && !args->ar_localcaching)
- goto cant_remount;
args->ar_localcaching = 1;
break;
case Opt_debug:
@@ -181,17 +126,13 @@ int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount)
args->ar_debug = 0;
break;
case Opt_upgrade:
- if (remount && !args->ar_upgrade)
- goto cant_remount;
args->ar_upgrade = 1;
break;
case Opt_acl:
args->ar_posix_acl = 1;
- sdp->sd_vfs->s_flags |= MS_POSIXACL;
break;
case Opt_noacl:
args->ar_posix_acl = 0;
- sdp->sd_vfs->s_flags &= ~MS_POSIXACL;
break;
case Opt_quota_off:
args->ar_quota = GFS2_QUOTA_OFF;
@@ -215,29 +156,15 @@ int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount)
args->ar_data = GFS2_DATA_ORDERED;
break;
case Opt_meta:
- if (remount && args->ar_meta != 1)
- goto cant_remount;
args->ar_meta = 1;
break;
case Opt_err:
default:
- fs_info(sdp, "unknown option: %s
", o);
- error = -EINVAL;
- goto out_error;
+ fs_info(sdp, "invalid mount option: %s
", o);
+ return -EINVAL;
}
}
-out_error:
- if (error)
- fs_info(sdp, "invalid mount option(s)
");
-
- if (data != data_arg)
- kfree(data);
-
- return error;
-
-cant_remount:
- fs_info(sdp, "can't remount with option %s
", o);
- return -EINVAL;
+ return 0;
}
diff --git a/fs/gfs2/mount.h b/fs/gfs2/mount.h
deleted file mode 100644
index 401288a..0000000
--- a/fs/gfs2/mount.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/*
- * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
- * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
- *
- * This copyrighted material is made available to anyone wishing to use,
- * modify, copy, or redistribute it subject to the terms and conditions
- * of the GNU General Public License version 2.
- */
-
-#ifndef __MOUNT_DOT_H__
-#define __MOUNT_DOT_H__
-
-struct gfs2_sbd;
-
-int gfs2_mount_args(struct gfs2_sbd *sdp, char *data_arg, int remount);
-
-#endif /* __MOUNT_DOT_H__ */
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index f91eebd..3eb49ed 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -25,7 +25,6 @@
#include "glock.h"
#include "glops.h"
#include "inode.h"
-#include "mount.h"
#include "recovery.h"
#include "rgrp.h"
#include "super.h"
@@ -1116,12 +1115,20 @@ static int fill_super(struct super_block *sb, void *data, int silent)
return -ENOMEM;
}
GFS2: Fix remount argument parsing
