The 'duplicates' bool argument is always true when efivar_init() is
called from its only caller so let's just drop it instead.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
efivar operation is updated when the tee_stmm_efi module is probed.
tee_stmm_efi module supports SetVariable runtime service, but user needs
to manually remount the efivarfs as RW to enable the write access if the
previous efivar operation does not support SetVariable and efivarfs is
mounted as read-only.
This commit notifies the update of efivar operation to efivarfs
subsystem, then drops SB_RDONLY flag if the efivar operation supports
SetVariable.
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
[ardb: use per-superblock instance of the notifier block]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
syzbot reports issues with concurrent fsopen()/fsconfig() invocations on
efivarfs, which are the result of the fact that the efivarfs list (which
caches the names and GUIDs of existing EFI variables) is a global
structure. In normal use, these issues are unlikely to trigger, even in
the presence of multiple mounts of efivarfs, but the execution pattern
used by the syzkaller reproducer may result in multiple instances of the
superblock that share the global efivarfs list, and this causes list
corruption when the list is reinitialized by one user while another is
traversing it.
So let's move the list head into the superblock s_fs_info field, so that
it will never be shared between distinct instances of the superblock. In
the common case, there will still be a single instance of this list, but
in the artificial syzkaller case, no list corruption can occur any
longer.
Reported-by: syzbot+1902c359bfcaf39c46f2@syzkaller.appspotmail.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Allow UEFI variables to be modified by non-root processes in order to
run sandboxed code. This doesn't change the behavior of mounting
efivarfs unless uid/gid are specified; by default both are set to root.
Signed-off-by: Jiao Zhou <jiaozhou@google.com>
Acked-by: Matthew Garrett <mgarrett@aurora.tech>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Move the fiddly bits of the efivar layer into its only remaining user,
efivarfs, and confine its use to that particular module. All other uses
of the EFI variable store have no need for this additional layer of
complexity, given that they either only read variables, or read and
write variables into a separate GUIDed namespace, and cannot be used to
manipulate EFI variables that are covered by the EFI spec and/or affect
the boot flow.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
"rm -rf" is bricking some peoples' laptops because of variables being
used to store non-reinitializable firmware driver data that's required
to POST the hardware.
These are 100% bugs, and they need to be fixed, but in the mean time it
shouldn't be easy to *accidentally* brick machines.
We have to have delete working, and picking which variables do and don't
work for deletion is quite intractable, so instead make everything
immutable by default (except for a whitelist), and make tools that
aren't quite so broad-spectrum unset the immutable flag.
Signed-off-by: Peter Jones <pjones@redhat.com>
Tested-by: Lee, Chun-Yi <jlee@suse.com>
Acked-by: Matthew Garrett <mjg59@coreos.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Now that efivarfs uses the efivar API, move it out of efivars.c and
into fs/efivarfs where it belongs. This move will eventually allow us
to enable the efivarfs code without having to also enable
CONFIG_EFI_VARS built, and vice versa.
Furthermore, things like,
mount -t efivarfs none /sys/firmware/efi/efivars
will now work if efivarfs is built as a module without requiring the
use of MODULE_ALIAS(), which would have been necessary when the
efivarfs code was part of efivars.c.
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Ard Biesheuvel