linux-stable/fs/debugfs
Ondrej Mosnacek 5881fa8dc2 debugfs: fix security_locked_down() call for SELinux
When (ia->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) is zero, then
the SELinux implementation of the locked_down hook might report a denial
even though the operation would actually be allowed.

To fix this, make sure that security_locked_down() is called only when
the return value will be taken into account (i.e. when changing one of
the problematic attributes).

Note: this was introduced by commit 5496197f9b ("debugfs: Restrict
debugfs when the kernel is locked down"), but it didn't matter at that
time, as the SELinux support came in later.

Fixes: 59438b4647 ("security,lockdown,selinux: implement SELinux lockdown")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Link: https://lore.kernel.org/r/20210507125304.144394-1-omosnace@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-18 18:05:59 +02:00
..
file.c Scheduler updates for this cycle are: 2021-04-28 13:33:57 -07:00
inode.c debugfs: fix security_locked_down() call for SELinux 2021-05-18 18:05:59 +02:00
internal.h debugfs: Add access restriction option 2020-07-23 17:10:25 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00