diff options
Diffstat (limited to 'fs/tracefs/event_inode.c')
-rw-r--r-- | fs/tracefs/event_inode.c | 59 |
1 files changed, 52 insertions, 7 deletions
diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 237c6f370ad9..9f64e7332796 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -185,17 +185,49 @@ static struct dentry *create_dir(const char *name, struct dentry *parent, void * /** * eventfs_set_ef_status_free - set the ef->status to free + * @ti: the tracefs_inode of the dentry * @dentry: dentry who's status to be freed * * eventfs_set_ef_status_free will be called if no more * references remain */ -void eventfs_set_ef_status_free(struct dentry *dentry) +void eventfs_set_ef_status_free(struct tracefs_inode *ti, struct dentry *dentry) { struct tracefs_inode *ti_parent; - struct eventfs_file *ef; + struct eventfs_inode *ei; + struct eventfs_file *ef, *tmp; + + /* The top level events directory may be freed by this */ + if (unlikely(ti->flags & TRACEFS_EVENT_TOP_INODE)) { + LIST_HEAD(ef_del_list); + + mutex_lock(&eventfs_mutex); + + ei = ti->private; + + /* Record all the top level files */ + list_for_each_entry_srcu(ef, &ei->e_top_files, list, + lockdep_is_held(&eventfs_mutex)) { + list_add_tail(&ef->del_list, &ef_del_list); + } + + /* Nothing should access this, but just in case! */ + ti->private = NULL; + + mutex_unlock(&eventfs_mutex); + + /* Now safely free the top level files and their children */ + list_for_each_entry_safe(ef, tmp, &ef_del_list, del_list) { + list_del(&ef->del_list); + eventfs_remove(ef); + } + + kfree(ei); + return; + } mutex_lock(&eventfs_mutex); + ti_parent = get_tracefs(dentry->d_parent->d_inode); if (!ti_parent || !(ti_parent->flags & TRACEFS_EVENT_INODE)) goto out; @@ -420,7 +452,8 @@ static int dcache_dir_open_wrapper(struct inode *inode, struct file *file) ei = ti->private; idx = srcu_read_lock(&eventfs_srcu); - list_for_each_entry_rcu(ef, &ei->e_top_files, list) { + list_for_each_entry_srcu(ef, &ei->e_top_files, list, + srcu_read_lock_held(&eventfs_srcu)) { create_dentry(ef, dentry, false); } srcu_read_unlock(&eventfs_srcu, idx); @@ -491,6 +524,9 @@ struct dentry *eventfs_create_events_dir(const char *name, struct tracefs_inode *ti; struct inode *inode; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return NULL; + if (IS_ERR(dentry)) return dentry; @@ -507,7 +543,7 @@ struct dentry *eventfs_create_events_dir(const char *name, INIT_LIST_HEAD(&ei->e_top_files); ti = get_tracefs(inode); - ti->flags |= TRACEFS_EVENT_INODE; + ti->flags |= TRACEFS_EVENT_INODE | TRACEFS_EVENT_TOP_INODE; ti->private = ei; inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; @@ -538,6 +574,9 @@ struct eventfs_file *eventfs_add_subsystem_dir(const char *name, struct eventfs_inode *ei_parent; struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return NULL; + if (!parent) return ERR_PTR(-EINVAL); @@ -569,6 +608,9 @@ struct eventfs_file *eventfs_add_dir(const char *name, { struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return NULL; + if (!ef_parent) return ERR_PTR(-EINVAL); @@ -606,6 +648,9 @@ int eventfs_add_events_file(const char *name, umode_t mode, struct eventfs_inode *ei; struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return -ENODEV; + if (!parent) return -EINVAL; @@ -654,6 +699,9 @@ int eventfs_add_file(const char *name, umode_t mode, { struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return -ENODEV; + if (!ef_parent) return -EINVAL; @@ -791,7 +839,6 @@ void eventfs_remove(struct eventfs_file *ef) void eventfs_remove_events_dir(struct dentry *dentry) { struct tracefs_inode *ti; - struct eventfs_inode *ei; if (!dentry || !dentry->d_inode) return; @@ -800,8 +847,6 @@ void eventfs_remove_events_dir(struct dentry *dentry) if (!ti || !(ti->flags & TRACEFS_EVENT_INODE)) return; - ei = ti->private; d_invalidate(dentry); dput(dentry); - kfree(ei); } |