diff options
Diffstat (limited to 'fs/notify/fanotify')
-rw-r--r-- | fs/notify/fanotify/fanotify.c | 26 | ||||
-rw-r--r-- | fs/notify/fanotify/fanotify.h | 1 | ||||
-rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 77 |
3 files changed, 64 insertions, 40 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index e5f7e47de68e..2fa99aeaa095 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -57,14 +57,26 @@ static int fanotify_merge(struct list_head *list, struct fsnotify_event *event) #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS static int fanotify_get_response(struct fsnotify_group *group, - struct fanotify_perm_event_info *event) + struct fanotify_perm_event_info *event, + struct fsnotify_iter_info *iter_info) { int ret; pr_debug("%s: group=%p event=%p\n", __func__, group, event); + /* + * fsnotify_prepare_user_wait() fails if we race with mark deletion. + * Just let the operation pass in that case. + */ + if (!fsnotify_prepare_user_wait(iter_info)) { + event->response = FAN_ALLOW; + goto out; + } + wait_event(group->fanotify_data.access_waitq, event->response); + fsnotify_finish_user_wait(iter_info); +out: /* userspace responded, convert to something usable */ switch (event->response) { case FAN_ALLOW: @@ -174,7 +186,8 @@ static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *fanotify_mark, u32 mask, const void *data, int data_type, - const unsigned char *file_name, u32 cookie) + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info) { int ret = 0; struct fanotify_event_info *event; @@ -215,7 +228,8 @@ static int fanotify_handle_event(struct fsnotify_group *group, #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS if (mask & FAN_ALL_PERM_EVENTS) { - ret = fanotify_get_response(group, FANOTIFY_PE(fsn_event)); + ret = fanotify_get_response(group, FANOTIFY_PE(fsn_event), + iter_info); fsnotify_destroy_event(group, fsn_event); } #endif @@ -248,8 +262,14 @@ static void fanotify_free_event(struct fsnotify_event *fsn_event) kmem_cache_free(fanotify_event_cachep, event); } +static void fanotify_free_mark(struct fsnotify_mark *fsn_mark) +{ + kmem_cache_free(fanotify_mark_cache, fsn_mark); +} + const struct fsnotify_ops fanotify_fsnotify_ops = { .handle_event = fanotify_handle_event, .free_group_priv = fanotify_free_group_priv, .free_event = fanotify_free_event, + .free_mark = fanotify_free_mark, }; diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 4500a74f8d38..4eb6f5efa282 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -2,6 +2,7 @@ #include <linux/path.h> #include <linux/slab.h> +extern struct kmem_cache *fanotify_mark_cache; extern struct kmem_cache *fanotify_event_cachep; extern struct kmem_cache *fanotify_perm_event_cachep; diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 2b37f2785834..907a481ac781 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -41,7 +41,7 @@ extern const struct fsnotify_ops fanotify_fsnotify_ops; -static struct kmem_cache *fanotify_mark_cache __read_mostly; +struct kmem_cache *fanotify_mark_cache __read_mostly; struct kmem_cache *fanotify_event_cachep __read_mostly; struct kmem_cache *fanotify_perm_event_cachep __read_mostly; @@ -295,27 +295,37 @@ static ssize_t fanotify_read(struct file *file, char __user *buf, } ret = copy_event_to_user(group, kevent, buf); + if (unlikely(ret == -EOPENSTALE)) { + /* + * We cannot report events with stale fd so drop it. + * Setting ret to 0 will continue the event loop and + * do the right thing if there are no more events to + * read (i.e. return bytes read, -EAGAIN or wait). + */ + ret = 0; + } + /* * Permission events get queued to wait for response. Other * events can be destroyed now. */ if (!(kevent->mask & FAN_ALL_PERM_EVENTS)) { fsnotify_destroy_event(group, kevent); - if (ret < 0) - break; } else { #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS - if (ret < 0) { + if (ret <= 0) { FANOTIFY_PE(kevent)->response = FAN_DENY; wake_up(&group->fanotify_data.access_waitq); - break; + } else { + spin_lock(&group->notification_lock); + list_add_tail(&kevent->list, + &group->fanotify_data.access_list); + spin_unlock(&group->notification_lock); } - spin_lock(&group->notification_lock); - list_add_tail(&kevent->list, - &group->fanotify_data.access_list); - spin_unlock(&group->notification_lock); #endif } + if (ret < 0) + break; buf += ret; count -= ret; } @@ -445,11 +455,6 @@ static const struct file_operations fanotify_fops = { .llseek = noop_llseek, }; -static void fanotify_free_mark(struct fsnotify_mark *fsn_mark) -{ - kmem_cache_free(fanotify_mark_cache, fsn_mark); -} - static int fanotify_find_path(int dfd, const char __user *filename, struct path *path, unsigned int flags) { @@ -511,13 +516,12 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, tmask &= ~FAN_ONDIR; oldmask = fsn_mark->mask; - fsnotify_set_mark_mask_locked(fsn_mark, tmask); + fsn_mark->mask = tmask; } else { __u32 tmask = fsn_mark->ignored_mask & ~mask; if (flags & FAN_MARK_ONDIR) tmask &= ~FAN_ONDIR; - - fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask); + fsn_mark->ignored_mask = tmask; } *destroy = !(fsn_mark->mask | fsn_mark->ignored_mask); spin_unlock(&fsn_mark->lock); @@ -534,7 +538,8 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group, int destroy_mark; mutex_lock(&group->mark_mutex); - fsn_mark = fsnotify_find_vfsmount_mark(group, mnt); + fsn_mark = fsnotify_find_mark(&real_mount(mnt)->mnt_fsnotify_marks, + group); if (!fsn_mark) { mutex_unlock(&group->mark_mutex); return -ENOENT; @@ -542,6 +547,8 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group, removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, &destroy_mark); + if (removed & real_mount(mnt)->mnt_fsnotify_mask) + fsnotify_recalc_mask(real_mount(mnt)->mnt_fsnotify_marks); if (destroy_mark) fsnotify_detach_mark(fsn_mark); mutex_unlock(&group->mark_mutex); @@ -549,9 +556,6 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group, fsnotify_free_mark(fsn_mark); fsnotify_put_mark(fsn_mark); - if (removed & real_mount(mnt)->mnt_fsnotify_mask) - fsnotify_recalc_vfsmount_mask(mnt); - return 0; } @@ -564,7 +568,7 @@ static int fanotify_remove_inode_mark(struct fsnotify_group *group, int destroy_mark; mutex_lock(&group->mark_mutex); - fsn_mark = fsnotify_find_inode_mark(group, inode); + fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group); if (!fsn_mark) { mutex_unlock(&group->mark_mutex); return -ENOENT; @@ -572,16 +576,16 @@ static int fanotify_remove_inode_mark(struct fsnotify_group *group, removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, &destroy_mark); + if (removed & inode->i_fsnotify_mask) + fsnotify_recalc_mask(inode->i_fsnotify_marks); if (destroy_mark) fsnotify_detach_mark(fsn_mark); mutex_unlock(&group->mark_mutex); if (destroy_mark) fsnotify_free_mark(fsn_mark); - /* matches the fsnotify_find_inode_mark() */ + /* matches the fsnotify_find_mark() */ fsnotify_put_mark(fsn_mark); - if (removed & inode->i_fsnotify_mask) - fsnotify_recalc_inode_mask(inode); return 0; } @@ -600,13 +604,13 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, tmask |= FAN_ONDIR; oldmask = fsn_mark->mask; - fsnotify_set_mark_mask_locked(fsn_mark, tmask); + fsn_mark->mask = tmask; } else { __u32 tmask = fsn_mark->ignored_mask | mask; if (flags & FAN_MARK_ONDIR) tmask |= FAN_ONDIR; - fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask); + fsn_mark->ignored_mask = tmask; if (flags & FAN_MARK_IGNORED_SURV_MODIFY) fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY; } @@ -629,8 +633,8 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, if (!mark) return ERR_PTR(-ENOMEM); - fsnotify_init_mark(mark, fanotify_free_mark); - ret = fsnotify_add_mark_locked(mark, group, inode, mnt, 0); + fsnotify_init_mark(mark, group); + ret = fsnotify_add_mark_locked(mark, inode, mnt, 0); if (ret) { fsnotify_put_mark(mark); return ERR_PTR(ret); @@ -648,7 +652,8 @@ static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, __u32 added; mutex_lock(&group->mark_mutex); - fsn_mark = fsnotify_find_vfsmount_mark(group, mnt); + fsn_mark = fsnotify_find_mark(&real_mount(mnt)->mnt_fsnotify_marks, + group); if (!fsn_mark) { fsn_mark = fanotify_add_new_mark(group, NULL, mnt); if (IS_ERR(fsn_mark)) { @@ -657,10 +662,9 @@ static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, } } added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); - mutex_unlock(&group->mark_mutex); - if (added & ~real_mount(mnt)->mnt_fsnotify_mask) - fsnotify_recalc_vfsmount_mask(mnt); + fsnotify_recalc_mask(real_mount(mnt)->mnt_fsnotify_marks); + mutex_unlock(&group->mark_mutex); fsnotify_put_mark(fsn_mark); return 0; @@ -686,7 +690,7 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, return 0; mutex_lock(&group->mark_mutex); - fsn_mark = fsnotify_find_inode_mark(group, inode); + fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group); if (!fsn_mark) { fsn_mark = fanotify_add_new_mark(group, inode, NULL); if (IS_ERR(fsn_mark)) { @@ -695,10 +699,9 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, } } added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); - mutex_unlock(&group->mark_mutex); - if (added & ~inode->i_fsnotify_mask) - fsnotify_recalc_inode_mask(inode); + fsnotify_recalc_mask(inode->i_fsnotify_marks); + mutex_unlock(&group->mark_mutex); fsnotify_put_mark(fsn_mark); return 0; |