| Message ID | 20210629191035.681913-2-krisman@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | File system wide monitoring | expand |
On Tue, Jun 29, 2021 at 10:11 PM Gabriel Krisman Bertazi <krisman@collabora.com> wrote: > > Some events, like the overflow event, are not mergeable, so they are not > hashed. But, when failing inside fsnotify_add_event for lack of space, > fsnotify_add_event() still calls the insert hook, which adds the > overflow event to the merge list. Add a check to prevent any kind of > unmergeable event to be inserted in the hashtable. > > Fixes: 94e00d28a680 ("fsnotify: use hash table for faster events merge") > Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> > Reviewed-by: Amir Goldstein <amir73il@gmail.com> > --- > Changes since v2: > - Do check for hashed events inside the insert hook (Amir) > --- > fs/notify/fanotify/fanotify.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c > index 057abd2cf887..310246f8d3f1 100644 > --- a/fs/notify/fanotify/fanotify.c > +++ b/fs/notify/fanotify/fanotify.c > @@ -702,6 +702,9 @@ static void fanotify_insert_event(struct fsnotify_group *group, > > assert_spin_locked(&group->notification_lock); > > + if (!fanotify_is_hashed_event(event->mask)) > + return; > + > pr_debug("%s: group=%p event=%p bucket=%u\n", __func__, > group, event, bucket); > > @@ -779,8 +782,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, > > fsn_event = &event->fse; > ret = fsnotify_add_event(group, fsn_event, fanotify_merge, > - fanotify_is_hashed_event(mask) ? > - fanotify_insert_event : NULL); > + fanotify_insert_event); > if (ret) { > /* Permission events shouldn't be merged */ > BUG_ON(ret == 1 && mask & FANOTIFY_PERM_EVENTS); > -- > 2.32.0 >
On Tue 29-06-21 15:10:21, Gabriel Krisman Bertazi wrote: > Some events, like the overflow event, are not mergeable, so they are not > hashed. But, when failing inside fsnotify_add_event for lack of space, > fsnotify_add_event() still calls the insert hook, which adds the > overflow event to the merge list. Add a check to prevent any kind of > unmergeable event to be inserted in the hashtable. > > Fixes: 94e00d28a680 ("fsnotify: use hash table for faster events merge") > Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Looks good. Feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > > --- > Changes since v2: > - Do check for hashed events inside the insert hook (Amir) > --- > fs/notify/fanotify/fanotify.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c > index 057abd2cf887..310246f8d3f1 100644 > --- a/fs/notify/fanotify/fanotify.c > +++ b/fs/notify/fanotify/fanotify.c > @@ -702,6 +702,9 @@ static void fanotify_insert_event(struct fsnotify_group *group, > > assert_spin_locked(&group->notification_lock); > > + if (!fanotify_is_hashed_event(event->mask)) > + return; > + > pr_debug("%s: group=%p event=%p bucket=%u\n", __func__, > group, event, bucket); > > @@ -779,8 +782,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, > > fsn_event = &event->fse; > ret = fsnotify_add_event(group, fsn_event, fanotify_merge, > - fanotify_is_hashed_event(mask) ? > - fanotify_insert_event : NULL); > + fanotify_insert_event); > if (ret) { > /* Permission events shouldn't be merged */ > BUG_ON(ret == 1 && mask & FANOTIFY_PERM_EVENTS); > -- > 2.32.0 >
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 057abd2cf887..310246f8d3f1 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -702,6 +702,9 @@ static void fanotify_insert_event(struct fsnotify_group *group, assert_spin_locked(&group->notification_lock); + if (!fanotify_is_hashed_event(event->mask)) + return; + pr_debug("%s: group=%p event=%p bucket=%u\n", __func__, group, event, bucket); @@ -779,8 +782,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, fsn_event = &event->fse; ret = fsnotify_add_event(group, fsn_event, fanotify_merge, - fanotify_is_hashed_event(mask) ? - fanotify_insert_event : NULL); + fanotify_insert_event); if (ret) { /* Permission events shouldn't be merged */ BUG_ON(ret == 1 && mask & FANOTIFY_PERM_EVENTS);
Some events, like the overflow event, are not mergeable, so they are not hashed. But, when failing inside fsnotify_add_event for lack of space, fsnotify_add_event() still calls the insert hook, which adds the overflow event to the merge list. Add a check to prevent any kind of unmergeable event to be inserted in the hashtable. Fixes: 94e00d28a680 ("fsnotify: use hash table for faster events merge") Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> --- Changes since v2: - Do check for hashed events inside the insert hook (Amir) --- fs/notify/fanotify/fanotify.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)