diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/notify/Kconfig | 2 | ||||
-rw-r--r-- | fs/notify/fanotify/fanotify.c | 27 | ||||
-rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 98 | ||||
-rw-r--r-- | fs/notify/fsnotify.c | 35 | ||||
-rw-r--r-- | fs/notify/inode_mark.c | 9 | ||||
-rw-r--r-- | fs/notify/inotify/inotify_user.c | 2 | ||||
-rw-r--r-- | fs/notify/vfsmount_mark.c | 6 |
7 files changed, 146 insertions, 33 deletions
diff --git a/fs/notify/Kconfig b/fs/notify/Kconfig index b388443c3a09..22c629eedd82 100644 --- a/fs/notify/Kconfig +++ b/fs/notify/Kconfig @@ -3,4 +3,4 @@ config FSNOTIFY source "fs/notify/dnotify/Kconfig" source "fs/notify/inotify/Kconfig" -#source "fs/notify/fanotify/Kconfig" +source "fs/notify/fanotify/Kconfig" diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 85366c78cc37..b04f88eed09e 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -131,6 +131,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, BUILD_BUG_ON(FAN_Q_OVERFLOW != FS_Q_OVERFLOW); BUILD_BUG_ON(FAN_OPEN_PERM != FS_OPEN_PERM); BUILD_BUG_ON(FAN_ACCESS_PERM != FS_ACCESS_PERM); + BUILD_BUG_ON(FAN_ONDIR != FS_ISDIR); pr_debug("%s: group=%p event=%p\n", __func__, group, event); @@ -160,20 +161,21 @@ static bool fanotify_should_send_event(struct fsnotify_group *group, __u32 event_mask, void *data, int data_type) { __u32 marks_mask, marks_ignored_mask; + struct path *path = data; pr_debug("%s: group=%p to_tell=%p inode_mark=%p vfsmnt_mark=%p " "mask=%x data=%p data_type=%d\n", __func__, group, to_tell, inode_mark, vfsmnt_mark, event_mask, data, data_type); - /* sorry, fanotify only gives a damn about files and dirs */ - if (!S_ISREG(to_tell->i_mode) && - !S_ISDIR(to_tell->i_mode)) - return false; - /* if we don't have enough info to send an event to userspace say no */ if (data_type != FSNOTIFY_EVENT_PATH) return false; + /* sorry, fanotify only gives a damn about files and dirs */ + if (!S_ISREG(path->dentry->d_inode->i_mode) && + !S_ISDIR(path->dentry->d_inode->i_mode)) + return false; + if (inode_mark && vfsmnt_mark) { marks_mask = (vfsmnt_mark->mask | inode_mark->mask); marks_ignored_mask = (vfsmnt_mark->ignored_mask | inode_mark->ignored_mask); @@ -194,16 +196,29 @@ static bool fanotify_should_send_event(struct fsnotify_group *group, BUG(); } + if (S_ISDIR(path->dentry->d_inode->i_mode) && + (marks_ignored_mask & FS_ISDIR)) + return false; + if (event_mask & marks_mask & ~marks_ignored_mask) return true; return false; } +static void fanotify_free_group_priv(struct fsnotify_group *group) +{ + struct user_struct *user; + + user = group->fanotify_data.user; + atomic_dec(&user->fanotify_listeners); + free_uid(user); +} + const struct fsnotify_ops fanotify_fsnotify_ops = { .handle_event = fanotify_handle_event, .should_send_event = fanotify_should_send_event, - .free_group_priv = NULL, + .free_group_priv = fanotify_free_group_priv, .free_event_priv = NULL, .freeing_mark = NULL, }; diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index bbcb98e7fcc6..063224812b7e 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -16,6 +16,10 @@ #include <asm/ioctls.h> +#define FANOTIFY_DEFAULT_MAX_EVENTS 16384 +#define FANOTIFY_DEFAULT_MAX_MARKS 8192 +#define FANOTIFY_DEFAULT_MAX_LISTENERS 128 + extern const struct fsnotify_ops fanotify_fsnotify_ops; static struct kmem_cache *fanotify_mark_cache __read_mostly; @@ -326,7 +330,7 @@ static ssize_t fanotify_read(struct file *file, char __user *buf, ret = -EAGAIN; if (file->f_flags & O_NONBLOCK) break; - ret = -EINTR; + ret = -ERESTARTSYS; if (signal_pending(current)) break; @@ -372,11 +376,10 @@ static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t static int fanotify_release(struct inode *ignored, struct file *file) { struct fsnotify_group *group = file->private_data; - struct fanotify_response_event *re, *lre; - - pr_debug("%s: file=%p group=%p\n", __func__, file, group); #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS + struct fanotify_response_event *re, *lre; + mutex_lock(&group->fanotify_data.access_mutex); group->fanotify_data.bypass_perm = true; @@ -554,18 +557,24 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, __u32 mask, unsigned int flags) { - __u32 oldmask; + __u32 oldmask = -1; spin_lock(&fsn_mark->lock); if (!(flags & FAN_MARK_IGNORED_MASK)) { oldmask = fsn_mark->mask; fsnotify_set_mark_mask_locked(fsn_mark, (oldmask | mask)); } else { - oldmask = fsn_mark->ignored_mask; - fsnotify_set_mark_ignored_mask_locked(fsn_mark, (oldmask | mask)); + __u32 tmask = fsn_mark->ignored_mask | mask; + fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask); if (flags & FAN_MARK_IGNORED_SURV_MODIFY) fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY; } + + if (!(flags & FAN_MARK_ONDIR)) { + __u32 tmask = fsn_mark->ignored_mask | FAN_ONDIR; + fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask); + } + spin_unlock(&fsn_mark->lock); return mask & ~oldmask; @@ -582,6 +591,9 @@ static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, if (!fsn_mark) { int ret; + if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks) + return -ENOSPC; + fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); if (!fsn_mark) return -ENOMEM; @@ -610,10 +622,23 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, pr_debug("%s: group=%p inode=%p\n", __func__, group, inode); + /* + * If some other task has this inode open for write we should not add + * an ignored mark, unless that ignored mark is supposed to survive + * modification changes anyway. + */ + if ((flags & FAN_MARK_IGNORED_MASK) && + !(flags & FAN_MARK_IGNORED_SURV_MODIFY) && + (atomic_read(&inode->i_writecount) > 0)) + return 0; + fsn_mark = fsnotify_find_inode_mark(group, inode); if (!fsn_mark) { int ret; + if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks) + return -ENOSPC; + fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); if (!fsn_mark) return -ENOMEM; @@ -637,6 +662,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) { struct fsnotify_group *group; int f_flags, fd; + struct user_struct *user; pr_debug("%s: flags=%d event_f_flags=%d\n", __func__, flags, event_f_flags); @@ -647,6 +673,12 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) if (flags & ~FAN_ALL_INIT_FLAGS) return -EINVAL; + user = get_current_user(); + if (atomic_read(&user->fanotify_listeners) > FANOTIFY_DEFAULT_MAX_LISTENERS) { + free_uid(user); + return -EMFILE; + } + f_flags = O_RDWR | FMODE_NONOTIFY; if (flags & FAN_CLOEXEC) f_flags |= O_CLOEXEC; @@ -658,12 +690,47 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) if (IS_ERR(group)) return PTR_ERR(group); + group->fanotify_data.user = user; + atomic_inc(&user->fanotify_listeners); + group->fanotify_data.f_flags = event_f_flags; #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS mutex_init(&group->fanotify_data.access_mutex); init_waitqueue_head(&group->fanotify_data.access_waitq); INIT_LIST_HEAD(&group->fanotify_data.access_list); #endif + switch (flags & FAN_ALL_CLASS_BITS) { + case FAN_CLASS_NOTIF: + group->priority = FS_PRIO_0; + break; + case FAN_CLASS_CONTENT: + group->priority = FS_PRIO_1; + break; + case FAN_CLASS_PRE_CONTENT: + group->priority = FS_PRIO_2; + break; + default: + fd = -EINVAL; + goto out_put_group; + } + + if (flags & FAN_UNLIMITED_QUEUE) { + fd = -EPERM; + if (!capable(CAP_SYS_ADMIN)) + goto out_put_group; + group->max_events = UINT_MAX; + } else { + group->max_events = FANOTIFY_DEFAULT_MAX_EVENTS; + } + + if (flags & FAN_UNLIMITED_MARKS) { + fd = -EPERM; + if (!capable(CAP_SYS_ADMIN)) + goto out_put_group; + group->fanotify_data.max_marks = UINT_MAX; + } else { + group->fanotify_data.max_marks = FANOTIFY_DEFAULT_MAX_MARKS; + } fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags); if (fd < 0) @@ -704,6 +771,12 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags, default: return -EINVAL; } + + if (mask & FAN_ONDIR) { + flags |= FAN_MARK_ONDIR; + mask &= ~FAN_ONDIR; + } + #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS if (mask & ~(FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD)) #else @@ -719,6 +792,16 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags, ret = -EINVAL; if (unlikely(filp->f_op != &fanotify_fops)) goto fput_and_out; + group = filp->private_data; + + /* + * group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not + * allowed to set permissions events. + */ + ret = -EINVAL; + if (mask & FAN_ALL_PERM_EVENTS && + group->priority == FS_PRIO_0) + goto fput_and_out; ret = fanotify_find_path(dfd, pathname, &path, flags); if (ret) @@ -729,7 +812,6 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags, inode = path.dentry->d_inode; else mnt = path.mnt; - group = filp->private_data; /* create/update an inode mark */ switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) { diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index 4498a208df94..20dc218707ca 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -84,16 +84,17 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode) } /* Notify this dentry's parent about a child's events. */ -void __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) +int __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) { struct dentry *parent; struct inode *p_inode; + int ret = 0; if (!dentry) dentry = path->dentry; if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED)) - return; + return 0; parent = dget_parent(dentry); p_inode = parent->d_inode; @@ -106,14 +107,16 @@ void __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask) mask |= FS_EVENT_ON_CHILD; if (path) - fsnotify(p_inode, mask, path, FSNOTIFY_EVENT_PATH, - dentry->d_name.name, 0); + ret = fsnotify(p_inode, mask, path, FSNOTIFY_EVENT_PATH, + dentry->d_name.name, 0); else - fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE, - dentry->d_name.name, 0); + ret = fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE, + dentry->d_name.name, 0); } dput(parent); + + return ret; } EXPORT_SYMBOL_GPL(__fsnotify_parent); @@ -252,20 +255,23 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, if (inode_group > vfsmount_group) { /* handle inode */ - send_to_group(to_tell, NULL, inode_mark, NULL, mask, data, - data_is, cookie, file_name, &event); + ret = send_to_group(to_tell, NULL, inode_mark, NULL, mask, data, + data_is, cookie, file_name, &event); /* we didn't use the vfsmount_mark */ vfsmount_group = NULL; } else if (vfsmount_group > inode_group) { - send_to_group(to_tell, mnt, NULL, vfsmount_mark, mask, data, - data_is, cookie, file_name, &event); + ret = send_to_group(to_tell, mnt, NULL, vfsmount_mark, mask, data, + data_is, cookie, file_name, &event); inode_group = NULL; } else { - send_to_group(to_tell, mnt, inode_mark, vfsmount_mark, - mask, data, data_is, cookie, file_name, - &event); + ret = send_to_group(to_tell, mnt, inode_mark, vfsmount_mark, + mask, data, data_is, cookie, file_name, + &event); } + if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS)) + goto out; + if (inode_group) inode_node = srcu_dereference(inode_node->next, &fsnotify_mark_srcu); @@ -273,7 +279,8 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, vfsmount_node = srcu_dereference(vfsmount_node->next, &fsnotify_mark_srcu); } - + ret = 0; +out: srcu_read_unlock(&fsnotify_mark_srcu, idx); /* * fsnotify_create_event() took a reference so the event can't be cleaned diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c index 21ed10660b80..4c29fcf557d1 100644 --- a/fs/notify/inode_mark.c +++ b/fs/notify/inode_mark.c @@ -177,7 +177,8 @@ void fsnotify_set_inode_mark_mask_locked(struct fsnotify_mark *mark, * Attach an initialized mark to a given inode. * These marks may be used for the fsnotify backend to determine which * event types should be delivered to which group and for which inodes. These - * marks are ordered according to the group's location in memory. + * marks are ordered according to priority, highest number first, and then by + * the group's location in memory. */ int fsnotify_add_inode_mark(struct fsnotify_mark *mark, struct fsnotify_group *group, struct inode *inode, @@ -211,7 +212,11 @@ int fsnotify_add_inode_mark(struct fsnotify_mark *mark, goto out; } - if (mark->group < lmark->group) + if (mark->group->priority < lmark->group->priority) + continue; + + if ((mark->group->priority == lmark->group->priority) && + (mark->group < lmark->group)) continue; hlist_add_before_rcu(&mark->i.i_list, &lmark->i.i_list); diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 24edc1185d53..444c305a468c 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -862,7 +862,7 @@ static int __init inotify_user_setup(void) BUILD_BUG_ON(IN_Q_OVERFLOW != FS_Q_OVERFLOW); BUILD_BUG_ON(IN_IGNORED != FS_IN_IGNORED); BUILD_BUG_ON(IN_EXCL_UNLINK != FS_EXCL_UNLINK); - BUILD_BUG_ON(IN_ISDIR != FS_IN_ISDIR); + BUILD_BUG_ON(IN_ISDIR != FS_ISDIR); BUILD_BUG_ON(IN_ONESHOT != FS_IN_ONESHOT); BUG_ON(hweight32(ALL_INOTIFY_BITS) != 21); diff --git a/fs/notify/vfsmount_mark.c b/fs/notify/vfsmount_mark.c index 56772b578fbd..85eebff6d0d7 100644 --- a/fs/notify/vfsmount_mark.c +++ b/fs/notify/vfsmount_mark.c @@ -169,7 +169,11 @@ int fsnotify_add_vfsmount_mark(struct fsnotify_mark *mark, goto out; } - if (mark->group < lmark->group) + if (mark->group->priority < lmark->group->priority) + continue; + + if ((mark->group->priority == lmark->group->priority) && + (mark->group < lmark->group)) continue; hlist_add_before_rcu(&mark->m.m_list, &lmark->m.m_list); |