On Fri, Apr 12, 2019 at 10:44:12AM +0200, Jan Kara wrote:
On Thu 11-04-19 11:26:27, Sasha Levin wrote:
This is a note to let you know that I've just added the patch titled
fanotify: Release SRCU lock when waiting for userspace responseto the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: fanotify-release-srcu-lock-when-waiting-for-userspac.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
I'd be careful with this series. You're missing at least the fixup series from Miklos culminating in f37650f1c7c7 "fanotify: fix fsnotify_prepare_user_wait() failure". And you seem to be missing also quite some prerequisites reworking lifetime of fsnotify marks (series culminating with f09b04a03e0 "fsnotify: Remove special handling of mark destruction on group shutdown"). So you're just introducing subtle use-after-free issues to fanotify code. Overall I think the chances for regressions here are much bigger than the problem you'll be fixing unless you'll go for something like wholesale update of fs/notify/* to state in f37650f1c7c7.
I've pulled this series based on the request here: https://lore.kernel.org/stable/20190411032430.17353-1-matthew.ruffell@canoni...
There are a few reasons why I'd prefer to keep it in:
1. It fixes a very real bug which has affected quite a few of our customers as well, so (at least for me) this is more than a minor bugfix.
2. It came with a straightforward testcase.
3. Given that Canonical pulled it in as well, it (hopefully) received more testing than some other random patches.
If there are missing patches here I'd be happy to take them in and re-test the kernel, but I'd really like to avoid *not* taking these patches just because we fear a regression but can't show it.
-- Thanks, Sasha