b6509f6a8c
This reverts commit e9c15badbb7b ("fs: Do not check if there is a
fsnotify watcher on pseudo inodes"). The commit intended to eliminate
fsnotify-related overhead for pseudo inodes but it is broken in
concept. inotify can receive events of pipe files under /proc/X/fd and
chromium relies on close and open events for sandboxing. Maxim Levitsky
reported the following
Chromium starts as a white rectangle, shows few white rectangles that
resemble its notifications and then crashes.
The stdout output from chromium:
[mlevitsk@starship ~]$chromium-freeworld
mesa: for the --simplifycfg-sink-common option: may only occur zero or one times!
mesa: for the --global-isel-abort option: may only occur zero or one times!
[3379:3379:0628/135151.440930:ERROR:browser_switcher_service.cc(238)] XXX Init()
../../sandbox/linux/seccomp-bpf-helpers/sigsys_handlers.cc:**CRASHING**:seccomp-bpf failure in syscall 0072
Received signal 11 SEGV_MAPERR 0000004a9048
Crashes are not universal but even if chromium does not crash, it certainly
does not work properly. While filtering just modify and access might be
safe, the benefit is not worth the risk hence the revert.
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Fixes: e9c15badbb7b ("fs: Do not check if there is a fsnotify watcher on pseudo inodes")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.