diff options
| -rw-r--r-- | drivers/isdn/capi/capifs.c | 3 | ||||
| -rw-r--r-- | fs/affs/super.c | 3 | ||||
| -rw-r--r-- | fs/afs/super.c | 4 | ||||
| -rw-r--r-- | fs/hpfs/super.c | 3 | ||||
| -rw-r--r-- | fs/namespace.c | 21 | ||||
| -rw-r--r-- | fs/reiserfs/super.c | 3 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 |
7 files changed, 25 insertions, 13 deletions
diff --git a/drivers/isdn/capi/capifs.c b/drivers/isdn/capi/capifs.c index b129409925af..8f9f3b5a3e8c 100644 --- a/drivers/isdn/capi/capifs.c +++ b/drivers/isdn/capi/capifs.c @@ -75,8 +75,7 @@ static int capifs_remount(struct super_block *s, int *flags, char *data) } } - kfree(s->s_options); - s->s_options = new_opt; + replace_mount_options(s, new_opt); config.setuid = setuid; config.setgid = setgid; diff --git a/fs/affs/super.c b/fs/affs/super.c index 5ce695e707fe..63f5183f263b 100644 --- a/fs/affs/super.c +++ b/fs/affs/super.c @@ -507,8 +507,7 @@ affs_remount(struct super_block *sb, int *flags, char *data) kfree(new_opts); return -EINVAL; } - kfree(sb->s_options); - sb->s_options = new_opts; + replace_mount_options(sb, new_opts); sbi->s_flags = mount_flags; sbi->s_mode = mode; diff --git a/fs/afs/super.c b/fs/afs/super.c index 2753f16dd315..76828e5f8a39 100644 --- a/fs/afs/super.c +++ b/fs/afs/super.c @@ -408,17 +408,17 @@ static int afs_get_sb(struct file_system_type *fs_type, deactivate_locked_super(sb); goto error; } - sb->s_options = new_opts; + save_mount_options(sb, new_opts); sb->s_flags |= MS_ACTIVE; } else { _debug("reuse"); - kfree(new_opts); ASSERTCMP(sb->s_flags, &, MS_ACTIVE); } simple_set_mnt(mnt, sb); afs_put_volume(params.volume); afs_put_cell(params.cell); + kfree(new_opts); _leave(" = 0 [%p]", sb); return 0; diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c index fecf402d7b8a..fc77965be841 100644 --- a/fs/hpfs/super.c +++ b/fs/hpfs/super.c @@ -423,8 +423,7 @@ static int hpfs_remount_fs(struct super_block *s, int *flags, char *data) if (!(*flags & MS_RDONLY)) mark_dirty(s); - kfree(s->s_options); - s->s_options = new_opts; + replace_mount_options(s, new_opts); return 0; diff --git a/fs/namespace.c b/fs/namespace.c index 0d2003fb4377..134d494158d9 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -695,12 +695,16 @@ static inline void mangle(struct seq_file *m, const char *s) */ int generic_show_options(struct seq_file *m, struct vfsmount *mnt) { - const char *options = mnt->mnt_sb->s_options; + const char *options; + + rcu_read_lock(); + options = rcu_dereference(mnt->mnt_sb->s_options); if (options != NULL && options[0]) { seq_putc(m, ','); mangle(m, options); } + rcu_read_unlock(); return 0; } @@ -721,11 +725,22 @@ EXPORT_SYMBOL(generic_show_options); */ void save_mount_options(struct super_block *sb, char *options) { - kfree(sb->s_options); - sb->s_options = kstrdup(options, GFP_KERNEL); + BUG_ON(sb->s_options); + rcu_assign_pointer(sb->s_options, kstrdup(options, GFP_KERNEL)); } EXPORT_SYMBOL(save_mount_options); +void replace_mount_options(struct super_block *sb, char *options) +{ + char *old = sb->s_options; + rcu_assign_pointer(sb->s_options, options); + if (old) { + synchronize_rcu(); + kfree(old); + } +} +EXPORT_SYMBOL(replace_mount_options); + #ifdef CONFIG_PROC_FS /* iterator */ static void *m_start(struct seq_file *m, loff_t *pos) diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c index d444fe0013a4..1215a4f50cd2 100644 --- a/fs/reiserfs/super.c +++ b/fs/reiserfs/super.c @@ -1316,8 +1316,7 @@ static int reiserfs_remount(struct super_block *s, int *mount_flags, char *arg) } out_ok: - kfree(s->s_options); - s->s_options = new_opts; + replace_mount_options(s, new_opts); return 0; out_err: diff --git a/include/linux/fs.h b/include/linux/fs.h index ed788426f464..3b534e527e09 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2368,6 +2368,7 @@ extern void file_update_time(struct file *file); extern int generic_show_options(struct seq_file *m, struct vfsmount *mnt); extern void save_mount_options(struct super_block *sb, char *options); +extern void replace_mount_options(struct super_block *sb, char *options); static inline ino_t parent_ino(struct dentry *dentry) { |