From d0a6a87e40da49cfc7954c491d3065a25a641b29 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Thu, 4 Oct 2018 00:25:38 +0300 Subject: fanotify: support reporting thread id instead of process id In order to identify which thread triggered the event in a multi-threaded program, add the FAN_REPORT_TID flag in fanotify_init to opt-in for reporting the event creator's thread id information. Signed-off-by: nixiaoming Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara --- fs/notify/fanotify/fanotify.c | 9 ++++++--- fs/notify/fanotify/fanotify.h | 2 +- fs/notify/fanotify/fanotify_user.c | 4 ++-- 3 files changed, 9 insertions(+), 6 deletions(-) (limited to 'fs/notify') diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 361e3a0a445c..5769cf3ff035 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -25,7 +25,7 @@ static bool should_merge(struct fsnotify_event *old_fsn, old = FANOTIFY_E(old_fsn); new = FANOTIFY_E(new_fsn); - if (old_fsn->inode == new_fsn->inode && old->tgid == new->tgid && + if (old_fsn->inode == new_fsn->inode && old->pid == new->pid && old->path.mnt == new->path.mnt && old->path.dentry == new->path.dentry) return true; @@ -171,7 +171,10 @@ struct fanotify_event_info *fanotify_alloc_event(struct fsnotify_group *group, goto out; init: __maybe_unused fsnotify_init_event(&event->fse, inode, mask); - event->tgid = get_pid(task_tgid(current)); + if (FAN_GROUP_FLAG(group, FAN_REPORT_TID)) + event->pid = get_pid(task_pid(current)); + else + event->pid = get_pid(task_tgid(current)); if (path) { event->path = *path; path_get(&event->path); @@ -270,7 +273,7 @@ static void fanotify_free_event(struct fsnotify_event *fsn_event) event = FANOTIFY_E(fsn_event); path_put(&event->path); - put_pid(event->tgid); + put_pid(event->pid); if (fanotify_is_perm_event(fsn_event->mask)) { kmem_cache_free(fanotify_perm_event_cachep, FANOTIFY_PE(fsn_event)); diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 88a8290a61cb..ea05b8a401e7 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -19,7 +19,7 @@ struct fanotify_event_info { * during this object's lifetime */ struct path path; - struct pid *tgid; + struct pid *pid; }; /* diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 14594e491d2b..e03be5071362 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -132,7 +132,7 @@ static int fill_event_metadata(struct fsnotify_group *group, metadata->vers = FANOTIFY_METADATA_VERSION; metadata->reserved = 0; metadata->mask = fsn_event->mask & FANOTIFY_OUTGOING_EVENTS; - metadata->pid = pid_vnr(event->tgid); + metadata->pid = pid_vnr(event->pid); if (unlikely(fsn_event->mask & FAN_Q_OVERFLOW)) metadata->fd = FAN_NOFD; else { @@ -944,7 +944,7 @@ COMPAT_SYSCALL_DEFINE6(fanotify_mark, */ static int __init fanotify_user_setup(void) { - BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 6); + BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 7); BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 9); fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, -- cgit