diff options
Diffstat (limited to 'fs/notify')
| -rw-r--r-- | fs/notify/dnotify/dnotify.c | 16 | ||||
| -rw-r--r-- | fs/notify/fanotify/fanotify.c | 443 | ||||
| -rw-r--r-- | fs/notify/fanotify/fanotify.h | 118 | ||||
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 218 | ||||
| -rw-r--r-- | fs/notify/fsnotify.c | 244 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify.h | 6 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_fsnotify.c | 51 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_user.c | 18 |
8 files changed, 806 insertions, 308 deletions
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c index 7a42c2ebe28d..5dcda8f20c04 100644 --- a/fs/notify/dnotify/dnotify.c +++ b/fs/notify/dnotify/dnotify.c @@ -70,13 +70,10 @@ static void dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark) * destroy the dnotify struct if it was not registered to receive multiple * events. */ -static int dnotify_handle_event(struct fsnotify_group *group, - struct inode *inode, - u32 mask, const void *data, int data_type, - const struct qstr *file_name, u32 cookie, - struct fsnotify_iter_info *iter_info) +static int dnotify_handle_event(struct fsnotify_mark *inode_mark, u32 mask, + struct inode *inode, struct inode *dir, + const struct qstr *name) { - struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info); struct dnotify_mark *dn_mark; struct dnotify_struct *dn; struct dnotify_struct **prev; @@ -84,10 +81,7 @@ static int dnotify_handle_event(struct fsnotify_group *group, __u32 test_mask = mask & ~FS_EVENT_ON_CHILD; /* not a dir, dnotify doesn't care */ - if (!S_ISDIR(inode->i_mode)) - return 0; - - if (WARN_ON(fsnotify_iter_vfsmount_mark(iter_info))) + if (!dir && !(mask & FS_ISDIR)) return 0; dn_mark = container_of(inode_mark, struct dnotify_mark, fsn_mark); @@ -127,7 +121,7 @@ static void dnotify_free_mark(struct fsnotify_mark *fsn_mark) } static const struct fsnotify_ops dnotify_fsnotify_ops = { - .handle_event = dnotify_handle_event, + .handle_inode_event = dnotify_handle_event, .free_mark = dnotify_free_mark, }; diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 85eda539b35f..c942910a8649 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -34,10 +34,6 @@ static bool fanotify_fh_equal(struct fanotify_fh *fh1, if (fh1->type != fh2->type || fh1->len != fh2->len) return false; - /* Do not merge events if we failed to encode fh */ - if (fh1->type == FILEID_INVALID) - return false; - return !fh1->len || !memcmp(fanotify_fh_buf(fh1), fanotify_fh_buf(fh2), fh1->len); } @@ -53,25 +49,47 @@ static bool fanotify_fid_event_equal(struct fanotify_fid_event *ffe1, fanotify_fh_equal(&ffe1->object_fh, &ffe2->object_fh); } +static bool fanotify_info_equal(struct fanotify_info *info1, + struct fanotify_info *info2) +{ + if (info1->dir_fh_totlen != info2->dir_fh_totlen || + info1->file_fh_totlen != info2->file_fh_totlen || + info1->name_len != info2->name_len) + return false; + + if (info1->dir_fh_totlen && + !fanotify_fh_equal(fanotify_info_dir_fh(info1), + fanotify_info_dir_fh(info2))) + return false; + + if (info1->file_fh_totlen && + !fanotify_fh_equal(fanotify_info_file_fh(info1), + fanotify_info_file_fh(info2))) + return false; + + return !info1->name_len || + !memcmp(fanotify_info_name(info1), fanotify_info_name(info2), + info1->name_len); +} + static bool fanotify_name_event_equal(struct fanotify_name_event *fne1, struct fanotify_name_event *fne2) { - /* - * Do not merge name events without dir fh. - * FAN_DIR_MODIFY does not encode object fh, so it may be empty. - */ - if (!fne1->dir_fh.len) + struct fanotify_info *info1 = &fne1->info; + struct fanotify_info *info2 = &fne2->info; + + /* Do not merge name events without dir fh */ + if (!info1->dir_fh_totlen) return false; - if (fne1->name_len != fne2->name_len || - !fanotify_fh_equal(&fne1->dir_fh, &fne2->dir_fh)) + if (!fanotify_fsid_equal(&fne1->fsid, &fne2->fsid)) return false; - return !memcmp(fne1->name, fne2->name, fne1->name_len); + return fanotify_info_equal(info1, info2); } static bool fanotify_should_merge(struct fsnotify_event *old_fsn, - struct fsnotify_event *new_fsn) + struct fsnotify_event *new_fsn) { struct fanotify_event *old, *new; @@ -83,22 +101,22 @@ static bool fanotify_should_merge(struct fsnotify_event *old_fsn, old->type != new->type || old->pid != new->pid) return false; + /* + * We want to merge many dirent events in the same dir (i.e. + * creates/unlinks/renames), but we do not want to merge dirent + * events referring to subdirs with dirent events referring to + * non subdirs, otherwise, user won't be able to tell from a + * mask FAN_CREATE|FAN_DELETE|FAN_ONDIR if it describes mkdir+ + * unlink pair or rmdir+create pair of events. + */ + if ((old->mask & FS_ISDIR) != (new->mask & FS_ISDIR)) + return false; + switch (old->type) { case FANOTIFY_EVENT_TYPE_PATH: return fanotify_path_equal(fanotify_event_path(old), fanotify_event_path(new)); case FANOTIFY_EVENT_TYPE_FID: - /* - * We want to merge many dirent events in the same dir (i.e. - * creates/unlinks/renames), but we do not want to merge dirent - * events referring to subdirs with dirent events referring to - * non subdirs, otherwise, user won't be able to tell from a - * mask FAN_CREATE|FAN_DELETE|FAN_ONDIR if it describes mkdir+ - * unlink pair or rmdir+create pair of events. - */ - if ((old->mask & FS_ISDIR) != (new->mask & FS_ISDIR)) - return false; - return fanotify_fid_event_equal(FANOTIFY_FE(old), FANOTIFY_FE(new)); case FANOTIFY_EVENT_TYPE_FID_NAME: @@ -208,24 +226,30 @@ out: static u32 fanotify_group_event_mask(struct fsnotify_group *group, struct fsnotify_iter_info *iter_info, u32 event_mask, const void *data, - int data_type) + int data_type, struct inode *dir) { __u32 marks_mask = 0, marks_ignored_mask = 0; - __u32 test_mask, user_mask = FANOTIFY_OUTGOING_EVENTS; + __u32 test_mask, user_mask = FANOTIFY_OUTGOING_EVENTS | + FANOTIFY_EVENT_FLAGS; const struct path *path = fsnotify_data_path(data, data_type); + unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS); struct fsnotify_mark *mark; int type; pr_debug("%s: report_mask=%x mask=%x data=%p data_type=%d\n", __func__, iter_info->report_mask, event_mask, data, data_type); - if (!FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { + if (!fid_mode) { /* Do we have path to open a file descriptor? */ if (!path) return 0; /* Path type events are only relevant for files and dirs */ if (!d_is_reg(path->dentry) && !d_can_lookup(path->dentry)) return 0; + } else if (!(fid_mode & FAN_REPORT_FID)) { + /* Do we have a directory inode to report? */ + if (!dir && !(event_mask & FS_ISDIR)) + return 0; } fsnotify_foreach_obj_type(type) { @@ -244,12 +268,12 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, continue; /* - * If the event is for a child and this mark doesn't care about - * events on a child, don't send it! + * If the event is for a child and this mark is on a parent not + * watching children, don't send it! */ if (event_mask & FS_EVENT_ON_CHILD && - (type != FSNOTIFY_OBJ_TYPE_INODE || - !(mark->mask & FS_EVENT_ON_CHILD))) + type == FSNOTIFY_OBJ_TYPE_INODE && + !(mark->mask & FS_EVENT_ON_CHILD)) continue; marks_mask |= mark->mask; @@ -264,67 +288,102 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group, * * For backward compatibility and consistency, do not report FAN_ONDIR * to user in legacy fanotify mode (reporting fd) and report FAN_ONDIR - * to user in FAN_REPORT_FID mode for all event types. + * to user in fid mode for all event types. + * + * We never report FAN_EVENT_ON_CHILD to user, but we do pass it in to + * fanotify_alloc_event() when group is reporting fid as indication + * that event happened on child. */ - if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { - /* Do not report FAN_ONDIR without any event */ - if (!(test_mask & ~FAN_ONDIR)) + if (fid_mode) { + /* Do not report event flags without any event */ + if (!(test_mask & ~FANOTIFY_EVENT_FLAGS)) return 0; } else { - user_mask &= ~FAN_ONDIR; + user_mask &= ~FANOTIFY_EVENT_FLAGS; } return test_mask & user_mask; } -static void fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode, - gfp_t gfp) +/* + * Check size needed to encode fanotify_fh. + * + * Return size of encoded fh without fanotify_fh header. + * Return 0 on failure to encode. + */ +static int fanotify_encode_fh_len(struct inode *inode) { - int dwords, type, bytes = 0; + int dwords = 0; + + if (!inode) + return 0; + + exportfs_encode_inode_fh(inode, NULL, &dwords, NULL); + + return dwords << 2; +} + +/* + * Encode fanotify_fh. + * + * Return total size of encoded fh including fanotify_fh header. + * Return 0 on failure to encode. + */ +static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode, + unsigned int fh_len, gfp_t gfp) +{ + int dwords, type = 0; char *ext_buf = NULL; void *buf = fh->buf; int err; + fh->type = FILEID_ROOT; + fh->len = 0; + fh->flags = 0; if (!inode) - goto out; + return 0; - dwords = 0; + /* + * !gpf means preallocated variable size fh, but fh_len could + * be zero in that case if encoding fh len failed. + */ err = -ENOENT; - type = exportfs_encode_inode_fh(inode, NULL, &dwords, NULL); - if (!dwords) + if (fh_len < 4 || WARN_ON_ONCE(fh_len % 4)) goto out_err; - bytes = dwords << 2; - if (bytes > FANOTIFY_INLINE_FH_LEN) { - /* Treat failure to allocate fh as failure to allocate event */ + /* No external buffer in a variable size allocated fh */ + if (gfp && fh_len > FANOTIFY_INLINE_FH_LEN) { + /* Treat failure to allocate fh as failure to encode fh */ err = -ENOMEM; - ext_buf = kmalloc(bytes, gfp); + ext_buf = kmalloc(fh_len, gfp); if (!ext_buf) goto out_err; *fanotify_fh_ext_buf_ptr(fh) = ext_buf; buf = ext_buf; + fh->flags |= FANOTIFY_FH_FLAG_EXT_BUF; } + dwords = fh_len >> 2; type = exportfs_encode_inode_fh(inode, buf, &dwords, NULL); err = -EINVAL; - if (!type || type == FILEID_INVALID || bytes != dwords << 2) + if (!type || type == FILEID_INVALID || fh_len != dwords << 2) goto out_err; fh->type = type; - fh->len = bytes; + fh->len = fh_len; - return; + return FANOTIFY_FH_HDR_LEN + fh_len; out_err: pr_warn_ratelimited("fanotify: failed to encode fid (type=%d, len=%d, err=%i)\n", - type, bytes, err); + type, fh_len, err); kfree(ext_buf); *fanotify_fh_ext_buf_ptr(fh) = NULL; -out: /* Report the event without a file identifier on encode error */ fh->type = FILEID_INVALID; fh->len = 0; + return 0; } /* @@ -335,27 +394,179 @@ out: * FS_ATTRIB reports the child inode even if reported on a watched parent. * FS_CREATE reports the modified dir inode and not the created inode. */ -static struct inode *fanotify_fid_inode(struct inode *to_tell, u32 event_mask, - const void *data, int data_type) +static struct inode *fanotify_fid_inode(u32 event_mask, const void *data, + int data_type, struct inode *dir) { if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS) - return to_tell; + return dir; + + return fsnotify_data_inode(data, data_type); +} + +/* + * The inode to use as identifier when reporting dir fid depends on the event. + * Report the modified directory inode on dirent modification events. + * Report the "victim" inode if "victim" is a directory. + * Report the parent inode if "victim" is not a directory and event is + * reported to parent. + * Otherwise, do not report dir fid. + */ +static struct inode *fanotify_dfid_inode(u32 event_mask, const void *data, + int data_type, struct inode *dir) +{ + struct inode *inode = fsnotify_data_inode(data, data_type); + + if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS) + return dir; + + if (S_ISDIR(inode->i_mode)) + return inode; + + return dir; +} + +static struct fanotify_event *fanotify_alloc_path_event(const struct path *path, + gfp_t gfp) +{ + struct fanotify_path_event *pevent; + + pevent = kmem_cache_alloc(fanotify_path_event_cachep, gfp); + if (!pevent) + return NULL; + + pevent->fae.type = FANOTIFY_EVENT_TYPE_PATH; + pevent->path = *path; + path_get(path); + + return &pevent->fae; +} - return (struct inode *)fsnotify_data_inode(data, data_type); +static struct fanotify_event *fanotify_alloc_perm_event(const struct path *path, + gfp_t gfp) +{ + struct fanotify_perm_event *pevent; + + pevent = kmem_cache_alloc(fanotify_perm_event_cachep, gfp); + if (!pevent) + return NULL; + + pevent->fae.type = FANOTIFY_EVENT_TYPE_PATH_PERM; + pevent->response = 0; + pevent->state = FAN_EVENT_INIT; + pevent->path = *path; + path_get(path); + + return &pevent->fae; } -struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, - struct inode *inode, u32 mask, - const void *data, int data_type, - const struct qstr *file_name, - __kernel_fsid_t *fsid) +static struct fanotify_event *fanotify_alloc_fid_event(struct inode *id, + __kernel_fsid_t *fsid, + gfp_t gfp) +{ + struct fanotify_fid_event *ffe; + + ffe = kmem_cache_alloc(fanotify_fid_event_cachep, gfp); + if (!ffe) + return NULL; + + ffe->fae.type = FANOTIFY_EVENT_TYPE_FID; + ffe->fsid = *fsid; + fanotify_encode_fh(&ffe->object_fh, id, fanotify_encode_fh_len(id), + gfp); + + return &ffe->fae; +} + +static struct fanotify_event *fanotify_alloc_name_event(struct inode *id, + __kernel_fsid_t *fsid, + const struct qstr *file_name, + struct inode *child, + gfp_t gfp) +{ + struct fanotify_name_event *fne; + struct fanotify_info *info; + struct fanotify_fh *dfh, *ffh; + unsigned int dir_fh_len = fanotify_encode_fh_len(id); + unsigned int child_fh_len = fanotify_encode_fh_len(child); + unsigned int size; + + size = sizeof(*fne) + FANOTIFY_FH_HDR_LEN + dir_fh_len; + if (child_fh_len) + size += FANOTIFY_FH_HDR_LEN + child_fh_len; + if (file_name) + size += file_name->len + 1; + fne = kmalloc(size, gfp); + if (!fne) + return NULL; + + fne->fae.type = FANOTIFY_EVENT_TYPE_FID_NAME; + fne->fsid = *fsid; + info = &fne->info; + fanotify_info_init(info); + dfh = fanotify_info_dir_fh(info); + info->dir_fh_totlen = fanotify_encode_fh(dfh, id, dir_fh_len, 0); + if (child_fh_len) { + ffh = fanotify_info_file_fh(info); + info->file_fh_totlen = fanotify_encode_fh(ffh, child, child_fh_len, 0); + } + if (file_name) + fanotify_info_copy_name(info, file_name); + + pr_debug("%s: ino=%lu size=%u dir_fh_len=%u child_fh_len=%u name_len=%u name='%.*s'\n", + __func__, id->i_ino, size, dir_fh_len, child_fh_len, + info->name_len, info->name_len, fanotify_info_name(info)); + + return &fne->fae; +} + +static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, + u32 mask, const void *data, + int data_type, struct inode *dir, + const struct qstr *file_name, + __kernel_fsid_t *fsid) { struct fanotify_event *event = NULL; - struct fanotify_fid_event *ffe = NULL; - struct fanotify_name_event *fne = NULL; gfp_t gfp = GFP_KERNEL_ACCOUNT; - struct inode *id = fanotify_fid_inode(inode, mask, data, data_type); + struct inode *id = fanotify_fid_inode(mask, data, data_type, dir); + struct inode *dirid = fanotify_dfid_inode(mask, data, data_type, dir); const struct path *path = fsnotify_data_path(data, data_type); + unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS); + struct inode *child = NULL; + bool name_event = false; + + if ((fid_mode & FAN_REPORT_DIR_FID) && dirid) { + /* + * With both flags FAN_REPORT_DIR_FID and FAN_REPORT_FID, we + * report the child fid for events reported on a non-dir child + * in addition to reporting the parent fid and maybe child name. + */ + if ((fid_mode & FAN_REPORT_FID) && + id != dirid && !(mask & FAN_ONDIR)) + child = id; + + id = dirid; + + /* + * We record file name only in a group with FAN_REPORT_NAME + * and when we have a directory inode to report. + * + * For directory entry modification event, we record the fid of + * the directory and the name of the modified entry. + * + * For event on non-directory that is reported to parent, we + * record the fid of the parent and the name of the child. + * + * Even if not reporting name, we need a variable length + * fanotify_name_event if reporting both parent and child fids. + */ + if (!(fid_mode & FAN_REPORT_NAME)) { + name_event = !!child; + file_name = NULL; + } else if ((mask & ALL_FSNOTIFY_DIRENT_EVENTS) || + !(mask & FAN_ONDIR)) { + name_event = true; + } + } /* * For queues with unlimited length lost events are not expected and @@ -372,87 +583,30 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, memalloc_use_memcg(group->memcg); if (fanotify_is_perm_event(mask)) { - struct fanotify_perm_event *pevent; - - pevent = kmem_cache_alloc(fanotify_perm_event_cachep, gfp); - if (!pevent) - goto out; - - event = &pevent->fae; - event->type = FANOTIFY_EVENT_TYPE_PATH_PERM; - pevent->response = 0; - pevent->state = FAN_EVENT_INIT; - goto init; - } - - /* - * For FAN_DIR_MODIFY event, we report the fid of the directory and - * the name of the modified entry. - * Allocate an fanotify_name_event struct and copy the name. - */ - if (mask & FAN_DIR_MODIFY && !(WARN_ON_ONCE(!file_name))) { - fne = kmalloc(sizeof(*fne) + file_name->len + 1, gfp); - if (!fne) - goto out; - - event = &fne->fae; - event->type = FANOTIFY_EVENT_TYPE_FID_NAME; - fne->name_len = file_name->len; - strcpy(fne->name, file_name->name); - goto init; - } - - if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { - ffe = kmem_cache_alloc(fanotify_fid_event_cachep, gfp); - if (!ffe) - goto out; - - event = &ffe->fae; - event->type = FANOTIFY_EVENT_TYPE_FID; + event = fanotify_alloc_perm_event(path, gfp); + } else if (name_event && (file_name || child)) { + event = fanotify_alloc_name_event(id, fsid, file_name, child, + gfp); + } else if (fid_mode) { + event = fanotify_alloc_fid_event(id, fsid, gfp); } else { - struct fanotify_path_event *pevent; - - pevent = kmem_cache_alloc(fanotify_path_event_cachep, gfp); - if (!pevent) - goto out; - - event = &pevent->fae; - event->type = FANOTIFY_EVENT_TYPE_PATH; + event = fanotify_alloc_path_event(path, gfp); } -init: + if (!event) + goto out; + /* * Use the victim inode instead of the watching inode as the id for * event queue, so event reported on parent is merged with event * reported on child when both directory and child watches exist. */ - fsnotify_init_event(&event->fse, (unsigned long)id); - event->mask = mask; + fanotify_init_event(event, (unsigned long)id, mask); if (FAN_GROUP_FLAG(group, FAN_REPORT_TID)) event->pid = get_pid(task_pid(current)); else event->pid = get_pid(task_tgid(current)); - if (fsid && fanotify_event_fsid(event)) - *fanotify_event_fsid(event) = *fsid; - - if (fanotify_event_object_fh(event)) - fanotify_encode_fh(fanotify_event_object_fh(event), id, gfp); - - if (fanotify_event_dir_fh(event)) - fanotify_encode_fh(fanotify_event_dir_fh(event), id, gfp); - - if (fanotify_event_has_path(event)) { - struct path *p = fanotify_event_path(event); - - if (path) { - *p = *path; - path_get(path); - } else { - p->mnt = NULL; - p->dentry = NULL; - } - } out: memalloc_unuse_memcg(); return event; @@ -491,9 +645,9 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info) return fsid; } -static int fanotify_handle_event(struct fsnotify_group *group, - struct inode *inode, - u32 mask, const void *data, int data_type, +static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, + const void *data, int data_type, + struct inode *dir, const struct qstr *file_name, u32 cookie, struct fsnotify_iter_info *iter_info) { @@ -512,7 +666,6 @@ static int fanotify_handle_event(struct fsnotify_group *group, BUILD_BUG_ON(FAN_MOVED_FROM != FS_MOVED_FROM); BUILD_BUG_ON(FAN_CREATE != FS_CREATE); BUILD_BUG_ON(FAN_DELETE != FS_DELETE); - BUILD_BUG_ON(FAN_DIR_MODIFY != FS_DIR_MODIFY); BUILD_BUG_ON(FAN_DELETE_SELF != FS_DELETE_SELF); BUILD_BUG_ON(FAN_MOVE_SELF != FS_MOVE_SELF); BUILD_BUG_ON(FAN_EVENT_ON_CHILD != FS_EVENT_ON_CHILD); @@ -526,12 +679,11 @@ static int fanotify_handle_event(struct fsnotify_group *group, BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 19); mask = fanotify_group_event_mask(group, iter_info, mask, data, - data_type); + data_type, dir); if (!mask) return 0; - pr_debug("%s: group=%p inode=%p mask=%x\n", __func__, group, inode, - mask); + pr_debug("%s: group=%p mask=%x\n", __func__, group, mask); if (fanotify_is_perm_event(mask)) { /* @@ -542,14 +694,14 @@ static int fanotify_handle_event(struct fsnotify_group *group, return 0; } - if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { + if (FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS)) { fsid = fanotify_get_fsid(iter_info); /* Racing with mark destruction or creation? */ if (!fsid.val[0] && !fsid.val[1]) return 0; } - event = fanotify_alloc_event(group, inode, mask, data, data_type, + event = fanotify_alloc_event(group, mask, data, data_type, dir, file_name, &fsid); ret = -ENOMEM; if (unlikely(!event)) { @@ -614,11 +766,7 @@ static void fanotify_free_fid_event(struct fanotify_event *event) static void fanotify_free_name_event(struct fanotify_event *event) { - struct fanotify_name_event *fne = FANOTIFY_NE(event); - - if (fanotify_fh_has_ext_buf(&fne->dir_fh)) - kfree(fanotify_fh_ext_buf(&fne->dir_fh)); - kfree(fne); + kfree(FANOTIFY_NE(event)); } static void fanotify_free_event(struct fsnotify_event *fsn_event) @@ -640,6 +788,9 @@ static void fanotify_free_event(struct fsnotify_event *fsn_event) case FANOTIFY_EVENT_TYPE_FID_NAME: fanotify_free_name_event(event); break; + case FANOTIFY_EVENT_TYPE_OVERFLOW: + kfree(event); + break; default: WARN_ON_ONCE(1); } diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 8ce7ccfc4b0d..896c819a1786 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -23,20 +23,41 @@ enum { * stored in either the first or last 2 dwords. */ #define FANOTIFY_INLINE_FH_LEN (3 << 2) +#define FANOTIFY_FH_HDR_LEN offsetof(struct fanotify_fh, buf) +/* Fixed size struct for file handle */ struct fanotify_fh { - unsigned char buf[FANOTIFY_INLINE_FH_LEN]; u8 type; u8 len; +#define FANOTIFY_FH_FLAG_EXT_BUF 1 + u8 flags; + u8 pad; + unsigned char buf[]; +} __aligned(4); + +/* Variable size struct for dir file handle + child file handle + name */ +struct fanotify_info { + /* size of dir_fh/file_fh including fanotify_fh hdr size */ + u8 dir_fh_totlen; + u8 file_fh_totlen; + u8 name_len; + u8 pad; + unsigned char buf[]; + /* + * (struct fanotify_fh) dir_fh starts at buf[0] + * (optional) file_fh starts at buf[dir_fh_totlen] + * name starts at buf[dir_fh_totlen + file_fh_totlen] + */ } __aligned(4); static inline bool fanotify_fh_has_ext_buf(struct fanotify_fh *fh) { - return fh->len > FANOTIFY_INLINE_FH_LEN; + return (fh->flags & FANOTIFY_FH_FLAG_EXT_BUF); } static inline char **fanotify_fh_ext_buf_ptr(struct fanotify_fh *fh) { + BUILD_BUG_ON(FANOTIFY_FH_HDR_LEN % 4); BUILD_BUG_ON(__alignof__(char *) - 4 + sizeof(char *) > FANOTIFY_INLINE_FH_LEN); return (char **)ALIGN((unsigned long)(fh->buf), __alignof__(char *)); @@ -52,6 +73,56 @@ static inline void *fanotify_fh_buf(struct fanotify_fh *fh) return fanotify_fh_has_ext_buf(fh) ? fanotify_fh_ext_buf(fh) : fh->buf; } +static inline int fanotify_info_dir_fh_len(struct fanotify_info *info) +{ + if (!info->dir_fh_totlen || + WARN_ON_ONCE(info->dir_fh_totlen < FANOTIFY_FH_HDR_LEN)) + return 0; + + return info->dir_fh_totlen - FANOTIFY_FH_HDR_LEN; +} + +static inline struct fanotify_fh *fanotify_info_dir_fh(struct fanotify_info *info) +{ + BUILD_BUG_ON(offsetof(struct fanotify_info, buf) % 4); + + return (struct fanotify_fh *)info->buf; +} + +static inline int fanotify_info_file_fh_len(struct fanotify_info *info) +{ + if (!info->file_fh_totlen || + WARN_ON_ONCE(info->file_fh_totlen < FANOTIFY_FH_HDR_LEN)) + return 0; + + return info->file_fh_totlen - FANOTIFY_FH_HDR_LEN; +} + +static inline struct fanotify_fh *fanotify_info_file_fh(struct fanotify_info *info) +{ + return (struct fanotify_fh *)(info->buf + info->dir_fh_totlen); +} + +static inline const char *fanotify_info_name(struct fanotify_info *info) +{ + return info->buf + info->dir_fh_totlen + info->file_fh_totlen; +} + +static inline void fanotify_info_init(struct fanotify_info *info) +{ + info->dir_fh_totlen = 0; + info->file_fh_totlen = 0; + info->name_len = 0; +} + +static inline void fanotify_info_copy_name(struct fanotify_info *info, + const struct qstr *name) +{ + info->name_len = name->len; + strcpy(info->buf + info->dir_fh_totlen + info->file_fh_totlen, + name->name); +} + /* * Common structure for fanotify events. Concrete structs are allocated in * fanotify_handle_event() and freed when the information is retrieved by @@ -63,6 +134,7 @@ enum fanotify_event_type { FANOTIFY_EVENT_TYPE_FID_NAME, /* variable length */ FANOTIFY_EVENT_TYPE_PATH, FANOTIFY_EVENT_TYPE_PATH_PERM, + FANOTIFY_EVENT_TYPE_OVERFLOW, /* struct fanotify_event */ }; struct fanotify_event { @@ -72,10 +144,20 @@ struct fanotify_event { struct pid *pid; }; +static inline void fanotify_init_event(struct fanotify_event *event, + unsigned long id, u32 mask) +{ + fsnotify_init_event(&event->fse, id); + event->mask = mask; + event->pid = NULL; +} + struct fanotify_fid_event { struct fanotify_event fae; __kernel_fsid_t fsid; struct fanotify_fh object_fh; + /* Reserve space in object_fh.buf[] - access with fanotify_fh_buf() */ + unsigned char _inline_fh_buf[FANOTIFY_INLINE_FH_LEN]; }; static inline struct fanotify_fid_event * @@ -87,9 +169,7 @@ FANOTIFY_FE(struct fanotify_event *event) struct fanotify_name_event { struct fanotify_event fae; __kernel_fsid_t fsid; - struct fanotify_fh dir_fh; - u8 name_len; - char name[]; + struct fanotify_info info; }; static inline struct fanotify_name_event * @@ -113,35 +193,37 @@ static inline struct fanotify_fh *fanotify_event_object_fh( { if (event->type == FANOTIFY_EVENT_TYPE_FID) return &FANOTIFY_FE(event)->object_fh; + else if (event->type == FANOTIFY_EVENT_TYPE_FID_NAME) + return fanotify_info_file_fh(&FANOTIFY_NE(event)->info); else return NULL; } -static inline struct fanotify_fh *fanotify_event_dir_fh( +static inline struct fanotify_info *fanotify_event_info( struct fanotify_event *event) { if (event->type == FANOTIFY_EVENT_TYPE_FID_NAME) - return &FANOTIFY_NE(event)->dir_fh; + return &FANOTIFY_NE(event)->info; else return NULL; } static inline int fanotify_event_object_fh_len(struct fanotify_event *event) { + struct fanotify_info *info = fanotify_event_info(event); struct fanotify_fh *fh = fanotify_event_object_fh(event); - return fh ? fh->len : 0; + if (info) + return info->file_fh_totlen ? fh->len : 0; + else + return fh ? fh->len : 0; } -static inline bool fanotify_event_has_name(struct fanotify_event *event) +static inline int fanotify_event_dir_fh_len(struct fanotify_event *event) { - return event->type == FANOTIFY_EVENT_TYPE_FID_NAME; -} + struct fanotify_info *info = fanotify_event_info(event); -static inline int fanotify_event_name_len(struct fanotify_event *event) -{ - return fanotify_event_has_name(event) ? - FANOTIFY_NE(event)->name_len : 0; + return info ? fanotify_info_dir_fh_len(info) : 0; } struct fanotify_path_event { @@ -202,9 +284,3 @@ static inline struct path *fanotify_event_path(struct fanotify_event *event) else return NULL; } - -struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, - struct inode *inode, u32 mask, - const void *data, int data_type, - const struct qstr *file_name, - __kernel_fsid_t *fsid); diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 63b5dffdca9e..559de311deca 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -64,21 +64,28 @@ static int fanotify_fid_info_len(int fh_len, int name_len) return roundup(FANOTIFY_INFO_HDR_LEN + info_len, FANOTIFY_EVENT_ALIGN); } -static int fanotify_event_info_len(struct fanotify_event *event) +static int fanotify_event_info_len(unsigned int fid_mode, + struct fanotify_event *event) { - int info_len = 0; + struct fanotify_info *info = fanotify_event_info(event); + int dir_fh_len = fanotify_event_dir_fh_len(event); int fh_len = fanotify_event_object_fh_len(event); + int info_len = 0; + int dot_len = 0; - if (fh_len) - info_len += fanotify_fid_info_len(fh_len, 0); - - if (fanotify_event_name_len(event)) { - struct fanotify_name_event *fne = FANOTIFY_NE(event); - - info_len += fanotify_fid_info_len(fne->dir_fh.len, - fne->name_len); + if (dir_fh_len) { + info_len += fanotify_fid_info_len(dir_fh_len, info->name_len); + } else if ((fid_mode & FAN_REPORT_NAME) && (event->mask & FAN_ONDIR)) { + /* + * With group flag FAN_REPORT_NAME, if name was not recorded in + * event on a directory, we will report the name ".". + */ + dot_len = 1; } + if (fh_len) + info_len += fanotify_fid_info_len(fh_len, dot_len); + return info_len; } @@ -93,6 +100,7 @@ static struct fanotify_event *get_one_event(struct fsnotify_group *group, { size_t event_size = FAN_EVENT_METADATA_LEN; struct fanotify_event *event = NULL; + unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS); pr_debug("%s: group=%p count=%zd\n", __func__, group, count); @@ -100,8 +108,8 @@ static struct fanotify_event *get_one_event(struct fsnotify_group *group, if (fsnotify_notify_queue_is_empty(group)) goto out; - if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { - event_size += fanotify_event_info_len( + if (fid_mode) { + event_size += fanotify_event_info_len(fid_mode, FANOTIFY_E(fsnotify_peek_first_event(group))); } @@ -218,7 +226,7 @@ static int process_access_response(struct fsnotify_group *group, } static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, - const char *name, size_t name_len, + int info_type, const char *name, size_t name_len, char __user *buf, size_t count) { struct fanotify_event_info_fid info = { }; @@ -231,7 +239,7 @@ static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, pr_debug("%s: fh_len=%zu name_len=%zu, info_len=%zu, count=%zu\n", __func__, fh_len, name_len, info_len, count); - if (!fh_len || (name && !name_len)) + if (!fh_len) return 0; if (WARN_ON_ONCE(len < sizeof(info) || len > count)) @@ -241,8 +249,21 @@ static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, * Copy event info fid header followed by variable sized file handle * and optionally followed by variable sized filename. */ - info.hdr.info_type = name_len ? FAN_EVENT_INFO_TYPE_DFID_NAME : - FAN_EVENT_INFO_TYPE_FID; + switch (info_type) { + case FAN_EVENT_INFO_TYPE_FID: + case FAN_EVENT_INFO_TYPE_DFID: + if (WARN_ON_ONCE(name_len)) + return -EFAULT; + break; + case FAN_EVENT_INFO_TYPE_DFID_NAME: + if (WARN_ON_ONCE(!name || !name_len)) + return -EFAULT; + break; + default: + return -EFAULT; + } + + info.hdr.info_type = info_type; info.hdr.len = len; info.fsid = *fsid; if (copy_to_user(buf, &info, sizeof(info))) @@ -305,13 +326,16 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group, { struct fanotify_event_metadata metadata; struct path *path = fanotify_event_path(event); + struct fanotify_info *info = fanotify_event_info(event); + unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS); struct file *f = NULL; int ret, fd = FAN_NOFD; + int info_type = 0; pr_debug("%s: group=%p event=%p\n", __func__, group, event); metadata.event_len = FAN_EVENT_METADATA_LEN + - fanotify_event_info_len(event); + fanotify_event_info_len(fid_mode, event); metadata.metadata_len = FAN_EVENT_METADATA_LEN; metadata.vers = FANOTIFY_METADATA_VERSION; metadata.reserved = 0; @@ -346,13 +370,13 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group, fd_install(fd, f); /* Event info records order is: dir fid + name, child fid */ - if (fanotify_event_name_len(event)) { - struct fanotify_name_event *fne = FANOTIFY_NE(event); - + if (fanotify_event_dir_fh_len(event)) { + info_type = info->name_len ? FAN_EVENT_INFO_TYPE_DFID_NAME : + FAN_EVENT_INFO_TYPE_DFID; ret = copy_info_to_user(fanotify_event_fsid(event), - fanotify_event_dir_fh(event), - fne->name, fne->name_len, - buf, count); + fanotify_info_dir_fh(info), + info_type, fanotify_info_name(info), + info->name_len, buf, count); if (ret < 0) return ret; @@ -361,9 +385,46 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group, } if (fanotify_event_object_fh_len(event)) { + const char *dot = NULL; + int dot_len = 0; + + if (fid_mode == FAN_REPORT_FID || info_type) { + /* + * With only group flag FAN_REPORT_FID only type FID is + * reported. Second info record type is always FID. + */ + info_type = FAN_EVENT_INFO_TYPE_FID; + } else if ((fid_mode & FAN_REPORT_NAME) && + (event->mask & FAN_ONDIR)) { + /* + * With group flag FAN_REPORT_NAME, if name was not + * recorded in an event on a directory, report the + * name "." with info type DFID_NAME. + */ + info_type = FAN_EVENT_INFO_TYPE_DFID_NAME; + dot = "."; + dot_len = 1; + } else if ((event->mask & ALL_FSNOTIFY_DIRENT_EVENTS) || + (event->mask & FAN_ONDIR)) { + /* + * With group flag FAN_REPORT_DIR_FID, a single info + * record has type DFID for directory entry modification + * event and for event on a directory. + */ + info_type = FAN_EVENT_INFO_TYPE_DFID; + } else { + /* + * With group flags FAN_REPORT_DIR_FID|FAN_REPORT_FID, + * a single info record has type FID for event on a + * non-directory, when there is no directory to report. + * For example, on FAN_DELETE_SELF event. + */ + info_type = FAN_EVENT_INFO_TYPE_FID; + } + ret = copy_info_to_user(fanotify_event_fsid(event), fanotify_event_object_fh(event), - NULL, 0, buf, count); + info_type, dot, dot_len, buf, count); if (ret < 0) return ret; @@ -412,6 +473,11 @@ static ssize_t fanotify_read(struct file *file, char __user *buf, add_wait_queue(&group->notification_waitq, &wait); while (1) { + /* + * User can supply arbitrarily large buffer. Avoid softlockups + * in case there are lots of available events. + */ + cond_resched(); event = get_one_event(group, count); if (IS_ERR(event)) { ret = PTR_ERR(event); @@ -651,12 +717,13 @@ out: } static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, - __u32 mask, - unsigned int flags, - int *destroy) + __u32 mask, unsigned int flags, + __u32 umask, int *destroy) { __u32 oldmask = 0; + /* umask bits cannot be removed by user */ + mask &= ~umask; spin_lock(&fsn_mark->lock); if (!(flags & FAN_MARK_IGNORED_MASK)) { oldmask = fsn_mark->mask; @@ -664,7 +731,13 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, } else { fsn_mark->ignored_mask &= ~mask; } - *destroy = !(fsn_mark->mask | fsn_mark->ignored_mask); + /* + * We need to keep the mark around even if remaining mask cannot + * result in any events (e.g. mask == FAN_ONDIR) to support incremenal + * changes to the mask. + * Destroy mark when only umask bits remain. + */ + *destroy = !((fsn_mark->mask | fsn_mark->ignored_mask) & ~umask); spin_unlock(&fsn_mark->lock); return mask & oldmask; @@ -672,7 +745,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, static int fanotify_remove_mark(struct fsnotify_group *group, fsnotify_connp_t *connp, __u32 mask, - unsigned int flags) + unsigned int flags, __u32 umask) { struct fsnotify_mark *fsn_mark = NULL; __u32 removed; @@ -686,7 +759,7 @@ static int fanotify_remove_mark(struct fsnotify_group *group, } removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, - &destroy_mark); + umask, &destroy_mark); if (removed & fsnotify_conn_mask(fsn_mark->connector)) fsnotify_recalc_mask(fsn_mark->connector); if (destroy_mark) @@ -702,25 +775,26 @@ static int fanotify_remove_mark(struct fsnotify_group *group, static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group, struct vfsmount *mnt, __u32 mask, - unsigned int flags) + unsigned int flags, __u32 umask) { return fanotify_remove_mark(group, &real_mount(mnt)->mnt_fsnotify_marks, - mask, flags); + mask, flags, umask); } static int fanotify_remove_sb_mark(struct fsnotify_group *group, - struct super_block *sb, __u32 mask, - unsigned int flags) + struct super_block *sb, __u32 mask, + unsigned int flags, __u32 umask) { - return fanotify_remove_mark(group, &sb->s_fsnotify_marks, mask, flags); + return fanotify_remove_mark(group, &sb->s_fsnotify_marks, mask, + flags, umask); } static int fanotify_remove_inode_mark(struct fsnotify_group *group, struct inode *inode, __u32 mask, - unsigned int flags) + unsigned int flags, __u32 umask) { return fanotify_remove_mark(group, &inode->i_fsnotify_marks, mask, - flags); + flags, umask); } static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, @@ -831,13 +905,28 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, FSNOTIFY_OBJ_TYPE_INODE, mask, flags, fsid); } +static struct fsnotify_event *fanotify_alloc_overflow_event(void) +{ + struct fanotify_event *oevent; + + oevent = kmalloc(sizeof(*oevent), GFP_KERNEL_ACCOUNT); + if (!oevent) + return NULL; + + fanotify_init_event(oevent, 0, FS_Q_OVERFLOW); + oevent->type = FANOTIFY_EVENT_TYPE_OVERFLOW; + + return &oevent->fse; +} + /* fanotify syscalls */ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) { struct fsnotify_group *group; int f_flags, fd; struct user_struct *user; - struct fanotify_event *oevent; + unsigned int fid_mode = flags & FANOTIFY_FID_BITS; + unsigned int class = flags & FANOTIFY_CLASS_BITS; pr_debug("%s: flags=%x event_f_flags=%x\n", __func__, flags, event_f_flags); @@ -864,8 +953,14 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) return -EINVAL; } - if ((flags & FAN_REPORT_FID) && - (flags & FANOTIFY_CLASS_BITS) != FAN_CLASS_NOTIF) + if (fid_mode && class != FAN_CLASS_NOTIF) + return -EINVAL; + + /* + * Child name is reported with parent fid so requires dir fid. + * We can report both child fid and dir fid with or without name. + */ + if ((fid_mode & FAN_REPORT_NAME) && !(fid_mode & FAN_REPORT_DIR_FID)) return -EINVAL; user = get_current_user(); @@ -892,20 +987,18 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) atomic_inc(&user->fanotify_listeners); group->memcg = get_mem_cgroup_from_mm(current->mm); - oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL, - FSNOTIFY_EVENT_NONE, NULL, NULL); - if (unlikely(!oevent)) { + group->overflow_event = fanotify_alloc_overflow_event(); + if (unlikely(!group->overflow_event)) { fd = -ENOMEM; goto out_destroy_group; } - group->overflow_event = &oevent->fse; if (force_o_largefile()) event_f_flags |= O_LARGEFILE; group->fanotify_data.f_flags = event_f_flags; init_waitqueue_head(&group->fanotify_data.access_waitq); INIT_LIST_HEAD(&group->fanotify_data.access_list); - switch (flags & FANOTIFY_CLASS_BITS) { + switch (class) { case FAN_CLASS_NOTIF: group->priority = FS_PRIO_0; break; @@ -1024,7 +1117,9 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, __kernel_fsid_t __fsid, *fsid = NULL; u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS; unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; - unsigned int obj_type; + bool ignored = flags & FAN_MARK_IGNORED_MASK; + unsigned int obj_type, fid_mode; + u32 umask = 0; int ret; pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n", @@ -1071,6 +1166,10 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, if (mask & ~valid_mask) return -EINVAL; + /* Event flags (ONDIR, ON_CHILD) are meaningless in ignored mask */ + if (ignored) + mask &= ~FANOTIFY_EVENT_FLAGS; + f = fdget(fanotify_fd); if (unlikely(!f.file)) return -EBADF; @@ -1097,9 +1196,9 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, * inode events are not supported on a mount mark, because they do not * carry enough information (i.e. path) to be filtered by mount point. */ + fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS); if (mask & FANOTIFY_INODE_EVENTS && - (!FAN_GROUP_FLAG(group, FAN_REPORT_FID) || - mark_type == FAN_MARK_MOUNT)) + (!fid_mode || mark_type == FAN_MARK_MOUNT)) goto fput_and_out; if (flags & FAN_MARK_FLUSH) { @@ -1124,7 +1223,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, goto path_put_and_out; } - if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) { + if (fid_mode) { ret = fanotify_test_fid(&path, &__fsid); if (ret) goto path_put_and_out; @@ -1138,6 +1237,19 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, else mnt = path.mnt; + /* Mask out FAN_EVENT_ON_CHILD flag for sb/mount/non-dir marks */ + if (mnt || !S_ISDIR(inode->i_mode)) { + mask &= ~FAN_EVENT_ON_CHILD; + umask = FAN_EVENT_ON_CHILD; + /* + * If group needs to report parent fid, register for getting + * events with parent/name info for non-directory. + */ + if ((fid_mode & FAN_REPORT_DIR_FID) && + (flags & FAN_MARK_ADD) && !ignored) + mask |= FAN_EVENT_ON_CHILD; + } + /* create/update an inode mark */ switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) { case FAN_MARK_ADD: @@ -1154,13 +1266,13 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, case FAN_MARK_REMOVE: if (mark_type == FAN_MARK_MOUNT) ret = fanotify_remove_vfsmount_mark(group, mnt, mask, - flags); + flags, umask); else if (mark_type == FAN_MARK_FILESYSTEM) ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask, - flags); + flags, umask); else ret = fanotify_remove_inode_mark(group, inode, mask, - flags); + flags, umask); break; default: ret = -EINVAL; @@ -1203,7 +1315,7 @@ COMPAT_SYSCALL_DEFINE6(fanotify_mark, */ static int __init fanotify_user_setup(void) { - BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 8); + BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 10); BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 9); fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index 72d332ce8e12..a960ec3a569a 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -74,7 +74,7 @@ static void fsnotify_unmount_inodes(struct super_block *sb) iput(iput_inode); /* for each watch, send FS_UNMOUNT and then remove it */ - fsnotify(inode, FS_UNMOUNT, inode, FSNOTIFY_EVENT_INODE, NULL, 0); + fsnotify_inode(inode, FS_UNMOUNT); fsnotify_inode_delete(inode); @@ -142,45 +142,140 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode) spin_unlock(&inode->i_lock); } -/* Notify this dentry's parent about a child's events. */ -int fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data, - int data_type) +/* Are inode/sb/mount interested in parent and name info with this event? */ +static bool fsnotify_event_needs_parent(struct inode *inode, struct mount *mnt, + __u32 mask) { + __u32 marks_mask = 0; + + /* We only send parent/name to inode/sb/mount for events on non-dir */ + if (mask & FS_ISDIR) + return false; + + /* Did either inode/sb/mount subscribe for events with parent/name? */ + marks_mask |= fsnotify_parent_needed_mask(inode->i_fsnotify_mask); + marks_mask |= fsnotify_parent_needed_mask(inode->i_sb->s_fsnotify_mask); + if (mnt) + marks_mask |= fsnotify_parent_needed_mask(mnt->mnt_fsnotify_mask); + + /* Did they subscribe for this event with parent/name info? */ + return mask & marks_mask; +} + +/* + * Notify this dentry's parent about a child's events with child name info + * if parent is watching or if inode/sb/mount are interested in events with + * parent and name info. + * + * Notify only the child without name info if parent is not watching and + * inode/sb/mount are not interested in events with parent and name info. + */ +int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data, + int data_type) +{ + const struct path *path = fsnotify_data_path(data, data_type); + struct mount *mnt = path ? real_mount(path->mnt) : NULL; + struct inode *inode = d_inode(dentry); struct dentry *parent; - struct inode *p_inode; + bool parent_watched = dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED; + __u32 p_mask; + struct inode *p_inode = NULL; + struct name_snapshot name; + struct qstr *file_name = NULL; int ret = 0; - if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED)) + /* + * Do inode/sb/mount care about parent and name info on non-dir? + * Do they care about any event at all? + */ + if (!inode->i_fsnotify_marks && !inode->i_sb->s_fsnotify_marks && + (!mnt || !mnt->mnt_fsnotify_marks) && !parent_watched) return 0; + parent = NULL; + if (!parent_watched && !fsnotify_event_needs_parent(inode, mnt, mask)) + goto notify; + + /* Does parent inode care about events on children? */ parent = dget_parent(dentry); p_inode = parent->d_inode; - - if (unlikely(!fsnotify_inode_watches_children(p_inode))) { + p_mask = fsnotify_inode_watches_children(p_inode); + if (unlikely(parent_watched && !p_mask)) __fsnotify_update_child_dentry_flags(p_inode); - } else if (p_inode->i_fsnotify_mask & mask & ALL_FSNOTIFY_EVENTS) { - struct name_snapshot name; - /* we are notifying a parent so come up with the new mask which - * specifies these are events which came from a child. */ - mask |= FS_EVENT_ON_CHILD; + /* + * Include parent/name in notification either if some notification + * groups require parent info (!parent_watched case) or the parent is + * interested in this event. + */ + if (!parent_watched || (mask & p_mask & ALL_FSNOTIFY_EVENTS)) { + /* When notifying parent, child should be passed as data */ + WARN_ON_ONCE(inode != fsnotify_data_inode(data, data_type)); + /* Notify both parent and child with child name info */ take_dentry_name_snapshot(&name, dentry); - ret = fsnotify(p_inode, mask, data, data_type, &name.name, 0); - release_dentry_name_snapshot(&name); + file_name = &name.name; + if (parent_watched) + mask |= FS_EVENT_ON_CHILD; } +notify: + ret = fsnotify(mask, data, data_type, p_inode, file_name, inode, 0); + + if (file_name) + release_dentry_name_snapshot(&name); dput(parent); return ret; } -EXPORT_SYMBOL_GPL(fsnotify_parent); +EXPORT_SYMBOL_GPL(__fsnotify_parent); + +static int fsnotify_handle_event(struct fsnotify_group *group, __u32 mask, + const void *data, int data_type, + struct inode *dir, const struct qstr *name, + u32 cookie, struct fsnotify_iter_info *iter_info) +{ + struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info); + struct fsnotify_mark *child_mark = fsnotify_iter_child_mark(iter_info); + struct inode *inode = fsnotify_data_inode(data, data_type); + const struct fsnotify_ops *ops = group->ops; + int ret; + + if (WARN_ON_ONCE(!ops->handle_inode_event)) + return 0; + + if (WARN_ON_ONCE(fsnotify_iter_sb_mark(iter_info)) || + WARN_ON_ONCE(fsnotify_iter_vfsmount_mark(iter_info))) + return 0; + + /* + * An event can be sent on child mark iterator instead of inode mark + * iterator because of other groups that have interest of this inode + * and have marks on both parent and child. We can simplify this case. + */ + if (!inode_mark) { + inode_mark = child_mark; + child_mark = NULL; + dir = NULL; + name = NULL; + } + + ret = ops->handle_inode_event(inode_mark, mask, inode, dir, name); + if (ret || !child_mark) + return ret; + + /* + * Some events can be sent on both parent dir and child marks + * (e.g. FS_ATTRIB). If both parent dir and child are watching, + * report the event once to parent dir with name and once to child + * without name. + */ + return ops->handle_inode_event(child_mark, mask, inode, NULL, NULL); +} -static int send_to_group(struct inode *to_tell, - __u32 mask, const void *data, - int data_is, u32 cookie, - const struct qstr *file_name, - struct fsnotify_iter_info *iter_info) +static int send_to_group(__u32 mask, const void *data, int data_type, + struct inode *dir, const struct qstr *file_name, + u32 cookie, struct fsnotify_iter_info *iter_info) { struct fsnotify_group *group = NULL; __u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS); @@ -216,16 +311,20 @@ static int send_to_group(struct inode *to_tell, } } - pr_debug("%s: group=%p to_tell=%p mask=%x marks_mask=%x marks_ignored_mask=%x" - " data=%p data_is=%d cookie=%d\n", - __func__, group, to_tell, mask, marks_mask, marks_ignored_mask, - data, data_is, cookie); + pr_debug("%s: group=%p mask=%x marks_mask=%x marks_ignored_mask=%x data=%p data_type=%d dir=%p cookie=%d\n", + __func__, group, mask, marks_mask, marks_ignored_mask, + data, data_type, dir, cookie); if (!(test_mask & marks_mask & ~marks_ignored_mask)) return 0; - return group->ops->handle_event(group, to_tell, mask, data, data_is, - file_name, cookie, iter_info); + if (group->ops->handle_event) { + return group->ops->handle_event(group, mask, data, data_type, dir, + file_name, cookie, iter_info); + } + + return fsnotify_handle_event(group, mask, data, data_type, dir, + file_name, cookie, iter_info); } static struct fsnotify_mark *fsnotify_first_mark(struct fsnotify_mark_connector **connp) @@ -303,29 +402,51 @@ static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info) } /* - * This is the main call to fsnotify. The VFS calls into hook specific functions - * in linux/fsnotify.h. Those functions then in turn call here. Here will call - * out to all of the registered fsnotify_group. Those groups can then use the - * notification event in whatever means they feel necessary. + * fsnotify - This is the main call to fsnotify. + * + * The VFS calls into hook specific functions in linux/fsnotify.h. + * Those functions then in turn call here. Here will call out to all of the + * registered fsnotify_group. Those groups can then use the notification event + * in whatever means they feel necessary. + * + * @mask: event type and flags + * @data: object that event happened on + * @data_type: type of object for fanotify_data_XXX() accessors + * @dir: optional directory associated with event - + * if @file_name is not NULL, this is the directory that + * @file_name is relative to + * @file_name: optional file name associated with event + * @inode: optional inode associated with event - + * either @dir or @inode must be non-NULL. + * if both are non-NULL event may be reported to both. + * @cookie: inotify rename cookie */ -int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, - const struct qstr *file_name, u32 cookie) +int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir, + const struct qstr *file_name, struct inode *inode, u32 cookie) { - const struct path *path = fsnotify_data_path(data, data_is); + const struct path *path = fsnotify_data_path(data, data_type); struct fsnotify_iter_info iter_info = {}; - struct super_block *sb = to_tell->i_sb; + struct super_block *sb; struct mount *mnt = NULL; - __u32 mnt_or_sb_mask = sb->s_fsnotify_mask; + struct inode *child = NULL; int ret = 0; - __u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS); + __u32 test_mask, marks_mask; - if (path) { + if (path) mnt = real_mount(path->mnt); - mnt_or_sb_mask |= mnt->mnt_fsnotify_mask; + + if (!inode) { + /* Dirent event - report on TYPE_INODE to dir */ + inode = dir; + } else if (mask & FS_EVENT_ON_CHILD) { + /* + * Event on child - report on TYPE_INODE to dir if it is + * watching children and on TYPE_CHILD to child. + */ + child = inode; + inode = dir; } - /* An event "on child" is not intended for a mount/sb mark */ - if (mask & FS_EVENT_ON_CHILD) - mnt_or_sb_mask = 0; + sb = inode->i_sb; /* * Optimization: srcu_read_lock() has a memory barrier which can @@ -334,28 +455,45 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, * SRCU because we have no references to any objects and do not * need SRCU to keep them "alive". */ - if (!to_tell->i_fsnotify_marks && !sb->s_fsnotify_marks && - (!mnt || !mnt->mnt_fsnotify_marks)) + if (!sb->s_fsnotify_marks && + (!mnt || !mnt->mnt_fsnotify_marks) && + (!inode || !inode->i_fsnotify_marks) && + (!child || !child->i_fsnotify_marks)) return 0; + + marks_mask = sb->s_fsnotify_mask; + if (mnt) + marks_mask |= mnt->mnt_fsnotify_mask; + if (inode) + marks_mask |= inode->i_fsnotify_mask; + if (child) + marks_mask |= child->i_fsnotify_mask; + + /* * if this is a modify event we may need to clear the ignored masks - * otherwise return if neither the inode nor the vfsmount/sb care about - * this type of event. + * otherwise return if none of the marks care about this type of event. */ - if (!(mask & FS_MODIFY) && - !(test_mask & (to_tell->i_fsnotify_mask | mnt_or_sb_mask))) + test_mask = (mask & ALL_FSNOTIFY_EVENTS); + if (!(mask & FS_MODIFY) && !(test_mask & marks_mask)) return 0; iter_info.srcu_idx = srcu_read_lock(&fsnotify_mark_srcu); - iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] = - fsnotify_first_mark(&to_tell->i_fsnotify_marks); iter_info.marks[FSNOTIFY_OBJ_TYPE_SB] = fsnotify_first_mark(&sb->s_fsnotify_marks); if (mnt) { iter_info.marks[FSNOTIFY_OBJ_TYPE_VFSMOUNT] = fsnotify_first_mark(&mnt->mnt_fsnotify_marks); } + if (inode) { + iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] = + fsnotify_first_mark(&inode->i_fsnotify_marks); + } + if (child) { + iter_info.marks[FSNOTIFY_OBJ_TYPE_CHILD] = + fsnotify_first_mark(&child->i_fsnotify_marks); + } /* * We need to merge inode/vfsmount/sb mark lists so that e.g. inode mark @@ -363,8 +501,8 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, * That's why this traversal is so complicated... */ while (fsnotify_iter_select_report_types(&iter_info)) { - ret = send_to_group(to_tell, mask, data, data_is, cookie, - file_name, &iter_info); + ret = send_to_group(mask, data, data_type, dir, file_name, + cookie, &iter_info); if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS)) goto out; @@ -383,7 +521,7 @@ static __init int fsnotify_init(void) { int ret; - BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 26); + BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 25); ret = init_srcu_struct(&fsnotify_mark_srcu); if (ret) diff --git a/fs/notify/inotify/inotify.h b/fs/notify/inotify/inotify.h index 3f246f7b8a92..4327d0e9c364 100644 --- a/fs/notify/inotify/inotify.h +++ b/fs/notify/inotify/inotify.h @@ -24,9 +24,9 @@ static inline struct inotify_event_info *INOTIFY_E(struct fsnotify_event *fse) extern void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group); -extern int inotify_handle_event(struct fsnotify_group *group, - struct inode *inode, - u32 mask, const void *data, int data_type, +extern int inotify_handle_event(struct fsnotify_group *group, u32 mask, + const void *data, int data_type, + struct inode *dir, const struct qstr *file_name, u32 cookie, struct fsnotify_iter_info *iter_info); diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index 2ebc89047153..a65cf8c9f600 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -39,7 +39,7 @@ static bool event_compare(struct fsnotify_event *old_fsn, if (old->mask & FS_IN_IGNORED) return false; if ((old->mask == new->mask) && - (old_fsn->objectid == new_fsn->objectid) && + (old->wd == new->wd) && (old->name_len == new->name_len) && (!old->name_len || !strcmp(old->name, new->name))) return true; @@ -55,14 +55,11 @@ static int inotify_merge(struct list_head *list, return event_compare(last_event, event); } -int inotify_handle_event(struct fsnotify_group *group, - struct inode *inode, - u32 mask, const void *data, int data_type, - const struct qstr *file_name, u32 cookie, - struct fsnotify_iter_info *iter_info) +static int inotify_one_event(struct fsnotify_group *group, u32 mask, + struct fsnotify_mark *inode_mark, + const struct path *path, + const struct qstr *file_name, u32 cookie) { - const struct path *path = fsnotify_data_path(data, data_type); - struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info); struct inotify_inode_mark *i_mark; struct inotify_event_info *event; struct fsnotify_event *fsn_event; @@ -70,9 +67,6 @@ int inotify_handle_event(struct fsnotify_group *group, int len = 0; int alloc_len = sizeof(struct inotify_event_info); - if (WARN_ON(fsnotify_iter_vfsmount_mark(iter_info))) - return 0; - if ((inode_mark->mask & FS_EXCL_UNLINK) && path && d_unlinked(path->dentry)) return 0; @@ -82,7 +76,7 @@ int inotify_handle_event(struct fsnotify_group *group, alloc_len += len + 1; } - pr_debug("%s: group=%p inode=%p mask=%x\n", __func__, group, inode, + pr_debug("%s: group=%p mark=%p mask=%x\n", __func__, group, inode_mark, mask); i_mark = container_of(inode_mark, struct inotify_inode_mark, @@ -116,7 +110,7 @@ int inotify_handle_event(struct fsnotify_group *group, mask &= ~IN_ISDIR; fsn_event = &event->fse; - fsnotify_init_event(fsn_event, (unsigned long)inode); + fsnotify_init_event(fsn_event, 0); event->mask = mask; event->wd = i_mark->wd; event->sync_cookie = cookie; @@ -136,6 +130,37 @@ int inotify_handle_event(struct fsnotify_group *group, return 0; } +int inotify_handle_event(struct fsnotify_group *group, u32 mask, + const void *data, int data_type, struct inode *dir, + const struct qstr *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info) +{ + const struct path *path = fsnotify_data_path(data, data_type); + struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info); + struct fsnotify_mark *child_mark = fsnotify_iter_child_mark(iter_info); + int ret = 0; + + if (WARN_ON(fsnotify_iter_vfsmount_mark(iter_info))) + return 0; + + /* + * Some events cannot be sent on both parent and child marks + * (e.g. IN_CREATE). Those events are always sent on inode_mark. + * For events that are possible on both parent and child (e.g. IN_OPEN), + * event is sent on inode_mark with name if the parent is watching and + * is sent on child_mark without name if child is watching. + * If both parent and child are watching, report the event with child's + * name here and report another event without child's name below. + */ + if (inode_mark) + ret = inotify_one_event(group, mask, inode_mark, path, + file_name, cookie); + if (ret || !child_mark) + return ret; + + return inotify_one_event(group, mask, child_mark, path, NULL, 0); +} + static void inotify_freeing_mark(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group) { inotify_ignored_and_remove_idr(fsn_mark, group); diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index f88bbcc9efeb..186722ba3894 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -75,15 +75,17 @@ struct ctl_table inotify_table[] = { }; #endif /* CONFIG_SYSCTL */ -static inline __u32 inotify_arg_to_mask(u32 arg) +static inline __u32 inotify_arg_to_mask(struct inode *inode, u32 arg) { __u32 mask; /* - * everything should accept their own ignored, cares about children, - * and should receive events when the inode is unmounted + * Everything should accept their own ignored and should receive events + * when the inode is unmounted. All directories care about children. */ - mask = (FS_IN_IGNORED | FS_EVENT_ON_CHILD | FS_UNMOUNT); + mask = (FS_IN_IGNORED | FS_UNMOUNT); + if (S_ISDIR(inode->i_mode)) + mask |= FS_EVENT_ON_CHILD; /* mask off the flags used to open the fd */ mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT | IN_EXCL_UNLINK)); @@ -490,8 +492,8 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, fsn_mark); /* Queue ignore event for the watch */ - inotify_handle_event(group, NULL, FS_IN_IGNORED, NULL, - FSNOTIFY_EVENT_NONE, NULL, 0, &iter_info); + inotify_handle_event(group, FS_IN_IGNORED, NULL, FSNOTIFY_EVENT_NONE, + NULL, NULL, 0, &iter_info); i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); /* remove this mark from the idr */ @@ -512,7 +514,7 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, int create = (arg & IN_MASK_CREATE); int ret; - mask = inotify_arg_to_mask(arg); + mask = inotify_arg_to_mask(inode, arg); fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group); if (!fsn_mark) @@ -565,7 +567,7 @@ static int inotify_new_watch(struct fsnotify_group *group, struct idr *idr = &group->inotify_data.idr; spinlock_t *idr_lock = &group->inotify_data.idr_lock; - mask = inotify_arg_to_mask(arg); + mask = inotify_arg_to_mask(inode, arg); tmp_i_mark = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); if (unlikely(!tmp_i_mark)) |