linux_dsm_epyc7002/include
Amir Goldstein 41bf5eed80 fsnotify: fix events reported to watching parent and child
commit fecc4559780d52d174ea05e3bf543669165389c3 upstream.

fsnotify_parent() used to send two separate events to backends when a
parent inode is watching children and the child inode is also watching.
In an attempt to avoid duplicate events in fanotify, we unified the two
backend callbacks to a single callback and handled the reporting of the
two separate events for the relevant backends (inotify and dnotify).
However the handling is buggy and can result in inotify and dnotify
listeners receiving events of the type they never asked for or spurious
events.

The problem is the unified event callback with two inode marks (parent and
child) is called when any of the parent and child inodes are watched and
interested in the event, but the parent inode's mark that is interested
in the event on the child is not necessarily the one we are currently
reporting to (it could belong to a different group).

So before reporting the parent or child event flavor to backend we need
to check that the mark is really interested in that event flavor.

The semantics of INODE and CHILD marks were hard to follow and made the
logic more complicated than it should have been.  Replace it with INODE
and PARENT marks semantics to hopefully make the logic more clear.

Thanks to Hugh Dickins for spotting a bug in the earlier version of this
patch.

Fixes: 497b0c5a7c ("fsnotify: send event to parent and child with single callback")
CC: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201202120713.702387-4-amir73il@gmail.com
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:54:18 +01:00
..
acpi PM: ACPI: PCI: Drop acpi_pm_set_bridge_wakeup() 2020-12-30 11:54:05 +01:00
asm-generic Merge branch 'for-5.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu 2020-11-15 08:57:19 -08:00
clocksource
crypto
drm drm: drm_print.h: fix kernel-doc markups 2020-10-27 11:21:39 +01:00
dt-bindings ARM: Devicetree updates 2020-10-24 10:44:18 -07:00
keys
kunit kunit: fix display of failed expectations for strings 2020-11-10 13:45:15 -07:00
kvm ARM: 2020-10-23 11:17:56 -07:00
linux fsnotify: fix events reported to watching parent and child 2020-12-30 11:54:18 +01:00
math-emu
media media: v4l2-fwnode: v4l2_fwnode_endpoint_parse caller must init vep argument 2020-12-30 11:53:11 +01:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2020-12-10 14:29:30 -08:00
pcmcia
ras
rdma RDMA/uverbs: Fix incorrect variable type 2020-12-30 11:53:47 +01:00
scsi scsi: libiscsi: Fix NOP race condition 2020-11-16 22:32:50 -05:00
soc net: mscc: ocelot: fix dropping of unknown IPv4 multicast on Seville 2020-12-05 15:41:34 -08:00
sound ASoC: Fixes for v5.11 2020-11-19 19:56:29 +01:00
target
trace trace: fix potenial dangerous pointer 2020-11-25 13:03:44 +01:00
uapi binder: add flag to clear buffer on txn complete 2020-12-30 11:54:09 +01:00
vdso
video gpu: ipu-v3: remove unused functions 2020-10-26 10:42:38 +01:00
xen xen: don't use page->lru for ZONE_DEVICE memory 2020-12-09 10:31:41 +01:00