[PATCH 1/3] inotify: do not send a block of zeros when no pathname is available

[PATCH 1/3] inotify: do not send a block of zeros when no pathname is available

[Eric Paris]

From: Brian Rogers <brian@xyzw.org>

When an event has no pathname, there's no need to pad it with a null byte and
therefore generate an inotify_event sized block of zeros. This fixes a
regression introduced by commit 0db501bd0610ee0c0aca84d927f90bcccd09e2bd where
my system wouldn't finish booting because some process was being confused by
this.

Signed-off-by: Brian Rogers <brian@xyzw.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
---

 fs/notify/inotify/inotify_user.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 0e781bc..b547ae1 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -180,7 +180,7 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
 	struct fsnotify_event_private_data *fsn_priv;
 	struct inotify_event_private_data *priv;
 	size_t event_size = sizeof(struct inotify_event);
-	size_t name_len;
+	size_t name_len = 0;
 
 	/* we get the inotify watch descriptor from the event private data */
 	spin_lock(&event->lock);
@@ -196,10 +196,12 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
 		inotify_free_event_priv(fsn_priv);
 	}
 
-	/* round up event->name_len so it is a multiple of event_size
+	/*
+	 * round up event->name_len so it is a multiple of event_size
 	 * plus an extra byte for the terminating '\0'.
 	 */
-	name_len = roundup(event->name_len + 1, event_size);
+	if (event->name_len)
+		name_len = roundup(event->name_len + 1, event_size);
 	inotify_event.len = name_len;
 
 	inotify_event.mask = inotify_mask_to_arg(event->mask);

[PATCH 2/3] inotify: fix length reporting and size checking

[Eric Paris]

0db501bd0610ee0c0 introduced a regresion in that it now sends a nul
terminator but the length accounting when checking for space or
reporting to userspace did not take this into account.  This corrects
all of the rounding logic.

Signed-off-by: Eric Paris <eparis@redhat.com>
---

 fs/notify/inotify/inotify_user.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index b547ae1..6111670 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -154,7 +154,8 @@ static struct fsnotify_event *get_one_event(struct fsnotify_group *group,
 
 	event = fsnotify_peek_notify_event(group);
 
-	event_size += roundup(event->name_len, event_size);
+	if (event->name_len)
+		event_size += roundup(event->name_len + 1, event_size);
 
 	if (event_size > count)
 		return ERR_PTR(-EINVAL);
@@ -327,8 +328,9 @@ static long inotify_ioctl(struct file *file, unsigned int cmd,
 		list_for_each_entry(holder, &group->notification_list, event_list) {
 			event = holder->event;
 			send_len += sizeof(struct inotify_event);
-			send_len += roundup(event->name_len,
-					     sizeof(struct inotify_event));
+			if (event->name_len)
+				send_len += roundup(event->name_len + 1,
+						sizeof(struct inotify_event));
 		}
 		mutex_unlock(&group->notification_mutex);
 		ret = put_user(send_len, (int __user *) p);

[PATCH 3/3] inotify: update the group mask on mark addition

[Eric Paris]

Seperating the addition and update of marks in inotify resulted in a
regression in that inotify never gets events.  The inotify group mask is
always 0.  This mask should be updated any time a new mark is added.

Signed-off-by: Eric Paris <eparis@redhat.com>
---

 fs/notify/inotify/inotify_user.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 6111670..dcd2040 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -591,6 +591,10 @@ retry:
 	/* match the ref from fsnotify_init_markentry() */
 	fsnotify_put_mark(&tmp_ientry->fsn_entry);
 
+	/* if this mark added a new event update the group mask */
+	if (mask & ~group->mask)
+		fsnotify_recalc_group_mask(group);
+
 out_err:
 	if (ret < 0)
 		kmem_cache_free(inotify_inode_mark_cachep, tmp_ientry);