(Adding bwh to CC - he maintains the 3.2 kernel.)On Do, 2017-11-16 at 20:43 +0100, Stefan Nuernberger wrote: > From: Will Woods <wwoods@xxxxxxxxxx> > > commit 1e2ee49f7f1b79f0b14884fe6a602f0411b39552 upstream. > > On 64-bit systems, O_LARGEFILE is automatically added to flags inside > the open() syscall (also openat(), blkdev_open(), etc). Userspace > therefore defines O_LARGEFILE to be 0 - you can use it, but it's a > no-op. Everything should be O_LARGEFILE by default. > > But: when fanotify does create_fd() it uses dentry_open(), which > skips > all that. And userspace can't set O_LARGEFILE in fanotify_init() > because it's defined to 0. So if fanotify gets an event regarding a > large file, the read() will just fail with -EOVERFLOW. > > This patch adds O_LARGEFILE to fanotify_init()'s event_f_flags on 64- > bit > systems, using the same test as open()/openat()/etc. > > Addresses https://bugzilla.redhat.com/show_bug.cgi?id=696821 > > Signed-off-by: Will Woods <wwoods@xxxxxxxxxx> > Acked-by: Eric Paris <eparis@xxxxxxxxxx> > Reviewed-by: Jan Kara <jack@xxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > > [snu: Backported to 3.2 / 3.10: adjusted context] > > Signed-off-by: Stefan Nuernberger <snu@xxxxxxxxxx> > Reviewed-by: Pawel Wieczorkiewicz <wipawel@xxxxxxxxx> > Reviewed-by: Simon Veith <sveith@xxxxxxxxx> > > Cc: <stable@xxxxxxxxxxxxxxx> # 3.2.x and 3.10.x > --- > fs/notify/fanotify/fanotify_user.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/notify/fanotify/fanotify_user.c > b/fs/notify/fanotify/fanotify_user.c > index d57995e1cfd7..dd3d9d13a4c4 100644 > --- a/fs/notify/fanotify/fanotify_user.c > +++ b/fs/notify/fanotify/fanotify_user.c > @@ -712,6 +712,9 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, > flags, unsigned int, event_f_flags) > group->fanotify_data.user = user; > atomic_inc(&user->fanotify_listeners); > > + if (force_o_largefile()) > + event_f_flags |= O_LARGEFILE; > + > group->fanotify_data.f_flags = event_f_flags; > #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS > mutex_init(&group->fanotify_data.access_mutex); Reviewed-by: Amit Shah <aams@xxxxxxxxxx> -- Amazon Development Center Germany GmbH Berlin - Dresden - Aachen main office: Krausenstr. 38, 10117 Berlin Geschaeftsfuehrer: Dr. Ralf Herbrich, Christian Schlaeger Ust-ID: DE289237879 Eingetragen am Amtsgericht Charlottenburg HRB 149173 B