Commit Graph

72 Commits

Author SHA1 Message Date
Linus Torvalds
13d88ac54d vfs-6.7.fsid
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Merge tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs fanotify fsid updates from Christian Brauner:
 "This work is part of the plan to enable fanotify to serve as a drop-in
  replacement for inotify. While inotify is availabe on all filesystems,
  fanotify currently isn't.

  In order to support fanotify on all filesystems two things are needed:

   (1) all filesystems need to support AT_HANDLE_FID

   (2) all filesystems need to report a non-zero f_fsid

  This contains (1) and allows filesystems to encode non-decodable file
  handlers for fanotify without implementing any exportfs operations by
  encoding a file id of type FILEID_INO64_GEN from i_ino and
  i_generation.

  Filesystems that want to opt out of encoding non-decodable file ids
  for fanotify that don't support NFS export can do so by providing an
  empty export_operations struct.

  This also partially addresses (2) by generating f_fsid for simple
  filesystems as well as freevxfs. Remaining filesystems will be dealt
  with by separate patches.

  Finally, this contains the patch from the current exportfs maintainers
  which moves exportfs under vfs with Chuck, Jeff, and Amir as
  maintainers and vfs.git as tree"

* tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  MAINTAINERS: create an entry for exportfs
  fs: fix build error with CONFIG_EXPORTFS=m or not defined
  freevxfs: derive f_fsid from bdev->bd_dev
  fs: report f_fsid from s_dev for "simple" filesystems
  exportfs: support encoding non-decodeable file handles by default
  exportfs: define FILEID_INO64_GEN* file handle types
  exportfs: make ->encode_fh() a mandatory method for NFS export
  exportfs: add helpers to check if filesystem can encode/decode file handles
2023-11-07 12:11:26 -08:00
Linus Torvalds
4c975a43fa EFI update for v6.7
- implement uid/gid mount options for efivarfs
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Merge tag 'efi-next-for-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI update from Ard Biesheuvel:
 "This is the only remaining EFI change, as everything else was taken
  via -tip this cycle:

   - implement uid/gid mount options for efivarfs"

* tag 'efi-next-for-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efivarfs: Add uid/gid mount options
2023-11-04 08:54:20 -10:00
Amir Goldstein
ae62bcb5e7
fs: report f_fsid from s_dev for "simple" filesystems
There are many "simple" filesystems (*) that report null f_fsid in
statfs(2).  Those "simple" filesystems report sb->s_dev as the st_dev
field of the stat syscalls for all inodes of the filesystem (**).

In order to enable fanotify reporting of events with fsid on those
"simple" filesystems, report the sb->s_dev number in f_fsid field of
statfs(2).

(*) For most of the "simple" filesystem refered to in this commit, the
->statfs() operation is simple_statfs(). Some of those fs assign the
simple_statfs() method directly in their ->s_op struct and some assign it
indirectly via a call to simple_fill_super() or to pseudo_fs_fill_super()
with either custom or "simple" s_op.
We also make the same change to efivarfs and hugetlbfs, although they do
not use simple_statfs(), because they use the simple_* inode opreations
(e.g. simple_lookup()).

(**) For most of the "simple" filesystems, the ->getattr() method is not
assigned, so stat() is implemented by generic_fillattr().  A few "simple"
filesystem use the simple_getattr() method which also calls
generic_fillattr() to fill most of the stat struct.

The two exceptions are procfs and 9p. procfs implements several different
->getattr() methods, but they all end up calling generic_fillattr() to
fill the st_dev field from sb->s_dev.

9p has more complicated ->getattr() methods, but they too, end up calling
generic_fillattr() to fill the st_dev field from sb->s_dev.

Note that 9p and kernfs also call simple_statfs() from custom ->statfs()
methods which already fill the f_fsid field, but v9fs_statfs() calls
simple_statfs() only in case f_fsid was not filled and kenrfs_statfs()
overwrites f_fsid after calling simple_statfs().

Link: https://lore.kernel.org/r/20230919094820.g5bwharbmy2dq46w@quack3/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231023143049.2944970-1-amir73il@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-28 16:16:18 +02:00
Jiao Zhou
5329aa5101 efivarfs: Add uid/gid mount options
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>
2023-10-20 00:47:18 +02:00
Jeff Layton
da06c204ff
efivarfs: convert to new timestamp accessors
Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-28-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-18 13:26:20 +02:00
Heinrich Schuchardt
79b83606ab efivarfs: fix statfs() on efivarfs
Some firmware (notably U-Boot) provides GetVariable() and
GetNextVariableName() but not QueryVariableInfo().

With commit d86ff3333c ("efivarfs: expose used and total size") the
statfs syscall was broken for such firmware.

If QueryVariableInfo() does not exist or returns EFI_UNSUPPORTED, just
report the file system size as 0 as statfs_simple() previously did.

Fixes: d86ff3333c ("efivarfs: expose used and total size")
Link: https://lore.kernel.org/all/20230910045445.41632-1-heinrich.schuchardt@canonical.com/
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
[ardb: log warning on QueryVariableInfo() failure]
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-09-11 09:10:02 +00:00
Jeff Layton
2fa9a97512 efivarfs: convert to ctime accessor functions
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-35-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-13 10:28:06 +02:00
Jeff Layton
73e6730650 efivarfs: update ctime when mtime changes on a write
POSIX says:

"Upon successful completion, where nbyte is greater than 0, write()
 shall mark for update the last data modification and last file status
 change timestamps of the file..."

Add the missing ctime update.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-3-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-10 10:04:51 +02:00
Anisse Astier
d86ff3333c efivarfs: expose used and total size
When writing EFI variables, one might get errors with no other message
on why it fails. Being able to see how much is used by EFI variables
helps analyzing such issues.

Since this is not a conventional filesystem, block size is intentionally
set to 1 instead of PAGE_SIZE.

x86 quirks of reserved size are taken into account; so that available
and free size can be different, further helping debugging space issues.

With this patch, one can see the remaining space in EFI variable storage
via efivarfs, like this:

   $ df -h /sys/firmware/efi/efivars/
   Filesystem      Size  Used Avail Use% Mounted on
   efivarfs        176K  106K   66K  62% /sys/firmware/efi/efivars

Signed-off-by: Anisse Astier <an.astier@criteo.com>
[ardb: - rename efi_reserved_space() to efivar_reserved_space()
       - whitespace/coding style tweaks]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-05-17 18:21:34 +02:00
Linus Torvalds
06e1a81c48 A healthy mix of EFI contributions this time:
- Performance tweaks for efifb earlycon by Andy
 
 - Preparatory refactoring and cleanup work in the efivar layer by Johan,
   which is needed to accommodate the Snapdragon arm64 laptops that
   expose their EFI variable store via a TEE secure world API.
 
 - Enhancements to the EFI memory map handling so that Xen dom0 can
   safely access EFI configuration tables (Demi Marie)
 
 - Wire up the newly introduced IBT/BTI flag in the EFI memory attributes
   table, so that firmware that is generated with ENDBR/BTI landing pads
   will be mapped with enforcement enabled.
 
 - Clean up how we check and print the EFI revision exposed by the
   firmware.
 
 - Incorporate EFI memory attributes protocol definition contributed by
   Evgeniy and wire it up in the EFI zboot code. This ensures that these
   images can execute under new and stricter rules regarding the default
   memory permissions for EFI page allocations. (More work is in progress
   here)
 
 - CPER header cleanup by Dan Williams
 
 - Use a raw spinlock to protect the EFI runtime services stack on arm64
   to ensure the correct semantics under -rt. (Pierre)
 
 - EFI framebuffer quirk for Lenovo Ideapad by Darrell.
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Merge tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI updates from Ard Biesheuvel:
 "A healthy mix of EFI contributions this time:

   - Performance tweaks for efifb earlycon (Andy)

   - Preparatory refactoring and cleanup work in the efivar layer, which
     is needed to accommodate the Snapdragon arm64 laptops that expose
     their EFI variable store via a TEE secure world API (Johan)

   - Enhancements to the EFI memory map handling so that Xen dom0 can
     safely access EFI configuration tables (Demi Marie)

   - Wire up the newly introduced IBT/BTI flag in the EFI memory
     attributes table, so that firmware that is generated with ENDBR/BTI
     landing pads will be mapped with enforcement enabled

   - Clean up how we check and print the EFI revision exposed by the
     firmware

   - Incorporate EFI memory attributes protocol definition and wire it
     up in the EFI zboot code (Evgeniy)

     This ensures that these images can execute under new and stricter
     rules regarding the default memory permissions for EFI page
     allocations (More work is in progress here)

   - CPER header cleanup (Dan Williams)

   - Use a raw spinlock to protect the EFI runtime services stack on
     arm64 to ensure the correct semantics under -rt (Pierre)

   - EFI framebuffer quirk for Lenovo Ideapad (Darrell)"

* tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (24 commits)
  firmware/efi sysfb_efi: Add quirk for Lenovo IdeaPad Duet 3
  arm64: efi: Make efi_rt_lock a raw_spinlock
  efi: Add mixed-mode thunk recipe for GetMemoryAttributes
  efi: x86: Wire up IBT annotation in memory attributes table
  efi: arm64: Wire up BTI annotation in memory attributes table
  efi: Discover BTI support in runtime services regions
  efi/cper, cxl: Remove cxl_err.h
  efi: Use standard format for printing the EFI revision
  efi: Drop minimum EFI version check at boot
  efi: zboot: Use EFI protocol to remap code/data with the right attributes
  efi/libstub: Add memory attribute protocol definitions
  efi: efivars: prevent double registration
  efi: verify that variable services are supported
  efivarfs: always register filesystem
  efi: efivars: add efivars printk prefix
  efi: Warn if trying to reserve memory under Xen
  efi: Actually enable the ESRT under Xen
  efi: Apply allowlist to EFI configuration tables when running under Xen
  efi: xen: Implement memory descriptor lookup based on hypercall
  efi: memmap: Disregard bogus entries instead of returning them
  ...
2023-02-23 14:41:48 -08:00
Johan Hovold
301de9a205 efivarfs: always register filesystem
The efivar ops are typically registered at subsys init time so that
they are available when efivarfs is registered at module init time.

Other efivars implementations, such as Google SMI, exist and can
currently be built as modules which means that efivar may not be
available when efivarfs is initialised.

Move the efivar availability check from module init to when the
filesystem is mounted to allow late registration of efivars.

Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-01-26 21:32:01 +01:00
Christian Brauner
8782a9aea3
fs: port ->fileattr_set() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:27 +01:00
Christian Brauner
6c960e68aa
fs: port ->create() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Johan Hovold
ade7fd908d efi: efivars: drop kobject from efivars_register()
Since commit 0f5b2c69a4 ("efi: vars: Remove deprecated 'efivars' sysfs
interface") and the removal of the sysfs interface there are no users of
the efivars kobject.

Drop the kobject argument from efivars_register() and add a new
efivar_is_available() helper in favour of the old efivars_kobject().

Note that the new helper uses the prefix 'efivar' (i.e. without an 's')
for consistency with efivar_supports_writes() and the rest of the
interface (except the registration functions).

For the benefit of drivers with optional EFI support, also provide a
dummy implementation of efivar_is_available().

Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-01-17 16:14:36 +01:00
Jason A. Donenfeld
63ffb573df efi: vars: prohibit reading random seed variables
In anticipation of putting random seeds in EFI variables, it's important
that the random GUID namespace of variables remains hidden from
userspace. We accomplish this by not populating efivarfs with entries
from that GUID, as well as denying the creation of new ones in that
GUID.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-12-01 09:51:21 +01:00
Ard Biesheuvel
8a254d90a7 efi: efivars: Fix variable writes without query_variable_store()
Commit bbc6d2c6ef ("efi: vars: Switch to new wrapper layer")
refactored the efivars layer so that the 'business logic' related to
which UEFI variables affect the boot flow in which way could be moved
out of it, and into the efivarfs driver.

This inadvertently broke setting variables on firmware implementations
that lack the QueryVariableInfo() boot service, because we no longer
tolerate a EFI_UNSUPPORTED result from check_var_size() when calling
efivar_entry_set_get_size(), which now ends up calling check_var_size()
a second time inadvertently.

If QueryVariableInfo() is missing, we support writes of up to 64k -
let's move that logic into check_var_size(), and drop the redundant
call.

Cc: <stable@vger.kernel.org> # v6.0
Fixes: bbc6d2c6ef ("efi: vars: Switch to new wrapper layer")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-10-21 11:09:40 +02:00
Ard Biesheuvel
2d82e6227e efi: vars: Move efivar caching layer into efivarfs
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>
2022-06-24 20:40:19 +02:00
Ard Biesheuvel
3a75f9f2f9 efi: vars: Use locking version to iterate over efivars linked lists
Both efivars and efivarfs uses __efivar_entry_iter() to go over the
linked list that shadows the list of EFI variables held by the firmware,
but fail to call the begin/end helpers that are documented as a
prerequisite.

So switch to the proper version, which is efivar_entry_iter(). Given
that in both cases, efivar_entry_remove() is invoked with the lock held
already, don't take the lock there anymore.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-06-24 20:40:19 +02:00
Ard Biesheuvel
ec3507b2ca efi: vars: Don't drop lock in the middle of efivar_init()
Even though the efivars_lock lock is documented as protecting the
efivars->ops pointer (among other things), efivar_init() happily
releases and reacquires the lock for every EFI variable that it
enumerates. This used to be needed because the lock was originally a
spinlock, which prevented the callback that is invoked for every
variable from being able to sleep. However, releasing the lock could
potentially invalidate the ops pointer, but more importantly, it might
allow a SetVariable() runtime service call to take place concurrently,
and the UEFI spec does not define how this affects an enumeration that
is running in parallel using the GetNextVariable() runtime service,
which is what efivar_init() uses.

In the meantime, the lock has been converted into a semaphore, and the
only reason we need to drop the lock is because the efivarfs pseudo
filesystem driver will otherwise deadlock when it invokes the efivars
API from the callback to create the efivar_entry items and insert them
into the linked list. (EFI pstore is affected in a similar way)

So let's switch to helpers that can be used while the lock is already
taken. This way, we can hold on to the lock throughout the enumeration.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-06-24 20:40:18 +02:00
Miklos Szeredi
d701ea284c efivars: convert to fileattr
Use the fileattr API to let the VFS handle locking, permission checking and
conversion.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
2021-04-12 15:04:29 +02:00
Christian Brauner
549c729771
fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:20 +01:00
Christian Brauner
21cb47be6f
inode: make init and permission helpers idmapped mount aware
The inode_owner_or_capable() helper determines whether the caller is the
owner of the inode or is capable with respect to that inode. Allow it to
handle idmapped mounts. If the inode is accessed through an idmapped
mount it according to the mount's user namespace. Afterwards the checks
are identical to non-idmapped mounts. If the initial user namespace is
passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Similarly, allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the
fsuid and fsgid of the caller from the mount's user namespace. If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Ard Biesheuvel
ff04f3b6f2 efivarfs: revert "fix memory leak in efivarfs_create()"
The memory leak addressed by commit fe5186cf12 is a false positive:
all allocations are recorded in a linked list, and freed when the
filesystem is unmounted. This leads to double frees, and as reported
by David, leads to crashes if SLUB is configured to self destruct when
double frees occur.

So drop the redundant kfree() again, and instead, mark the offending
pointer variable so the allocation is ignored by kmemleak.

Cc: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Fixes: fe5186cf12 ("efivarfs: fix memory leak in efivarfs_create()")
Reported-by: David Laight <David.Laight@aculab.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-11-25 16:55:02 +01:00
Vamshi K Sthambamkadi
fe5186cf12 efivarfs: fix memory leak in efivarfs_create()
kmemleak report:
  unreferenced object 0xffff9b8915fcb000 (size 4096):
  comm "efivarfs.sh", pid 2360, jiffies 4294920096 (age 48.264s)
  hex dump (first 32 bytes):
    2d 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  -...............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000cc4d897c>] kmem_cache_alloc_trace+0x155/0x4b0
    [<000000007d1dfa72>] efivarfs_create+0x6e/0x1a0
    [<00000000e6ee18fc>] path_openat+0xe4b/0x1120
    [<000000000ad0414f>] do_filp_open+0x91/0x100
    [<00000000ce93a198>] do_sys_openat2+0x20c/0x2d0
    [<000000002a91be6d>] do_sys_open+0x46/0x80
    [<000000000a854999>] __x64_sys_openat+0x20/0x30
    [<00000000c50d89c9>] do_syscall_64+0x38/0x90
    [<00000000cecd6b5f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

In efivarfs_create(), inode->i_private is setup with efivar_entry
object which is never freed.

Cc: <stable@vger.kernel.org>
Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Link: https://lore.kernel.org/r/20201023115429.GA2479@cosmos
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-10-26 08:15:24 +01:00
Michael Schaller
336af6a468 efivarfs: Replace invalid slashes with exclamation marks in dentries.
Without this patch efivarfs_alloc_dentry creates dentries with slashes in
their name if the respective EFI variable has slashes in its name. This in
turn causes EIO on getdents64, which prevents a complete directory listing
of /sys/firmware/efi/efivars/.

This patch replaces the invalid shlashes with exclamation marks like
kobject_set_name_vargs does for /sys/firmware/efi/vars/ to have consistently
named dentries under /sys/firmware/efi/vars/ and /sys/firmware/efi/efivars/.

Signed-off-by: Michael Schaller <misch@google.com>
Link: https://lore.kernel.org/r/20200925074502.150448-1-misch@google.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-09-25 23:29:04 +02:00
Ard Biesheuvel
f88814cc25 efi/efivars: Expose RT service availability via efivars abstraction
Commit

  bf67fad19e ("efi: Use more granular check for availability for variable services")

introduced a check into the efivarfs, efi-pstore and other drivers that
aborts loading of the module if not all three variable runtime services
(GetVariable, SetVariable and GetNextVariable) are supported. However, this
results in efivarfs being unavailable entirely if only SetVariable support
is missing, which is only needed if you want to make any modifications.
Also, efi-pstore and the sysfs EFI variable interface could be backed by
another implementation of the 'efivars' abstraction, in which case it is
completely irrelevant which services are supported by the EFI firmware.

So make the generic 'efivars' abstraction dependent on the availibility of
the GetVariable and GetNextVariable EFI runtime services, and add a helper
'efivar_supports_writes()' to find out whether the currently active efivars
abstraction supports writes (and wire it up to the availability of
SetVariable for the generic one).

Then, use the efivar_supports_writes() helper to decide whether to permit
efivarfs to be mounted read-write, and whether to enable efi-pstore or the
sysfs EFI variable interface altogether.

Fixes: bf67fad19e ("efi: Use more granular check for availability for variable services")
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-07-09 10:14:29 +03:00
Tony Luck
4353f03317 efivarfs: Don't return -EINTR when rate-limiting reads
Applications that read EFI variables may see a return
value of -EINTR if they exceed the rate limit and a
signal delivery is attempted while the process is sleeping.

This is quite surprising to the application, which probably
doesn't have code to handle it.

Change the interruptible sleep to a non-interruptible one.

Reported-by: Lennart Poettering <mzxreary@0pointer.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20200528194905.690-3-tony.luck@intel.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-15 14:38:56 +02:00
Tony Luck
2096721f15 efivarfs: Update inode modification time for successful writes
Some applications want to be able to see when EFI variables
have been updated.

Update the modification time for successful writes.

Reported-by: Lennart Poettering <mzxreary@0pointer.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20200528194905.690-2-tony.luck@intel.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-15 14:38:56 +02:00
Ard Biesheuvel
bf67fad19e efi: Use more granular check for availability for variable services
The UEFI spec rev 2.8 permits firmware implementations to support only
a subset of EFI runtime services at OS runtime (i.e., after the call to
ExitBootServices()), so let's take this into account in the drivers that
rely specifically on the availability of the EFI variable services.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Linus Torvalds
933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Linus Torvalds
5010fe9f09 New for 5.3:
- Standardize parameter checking for the SETFLAGS and FSSETXATTR ioctls
   (which were the file attribute setters for ext4 and xfs and have now
   been hoisted to the vfs)
 - Only allow the DAX flag to be set on files and directories.
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Merge tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull common SETFLAGS/FSSETXATTR parameter checking from Darrick Wong:
 "Here's a patch series that sets up common parameter checking functions
  for the FS_IOC_SETFLAGS and FS_IOC_FSSETXATTR ioctl implementations.

  The goal here is to reduce the amount of behaviorial variance between
  the filesystems where those ioctls originated (ext2 and XFS,
  respectively) and everybody else.

   - Standardize parameter checking for the SETFLAGS and FSSETXATTR
     ioctls (which were the file attribute setters for ext4 and xfs and
     have now been hoisted to the vfs)

   - Only allow the DAX flag to be set on files and directories"

* tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  vfs: only allow FSSETXATTR to set DAX flag on files and dirs
  vfs: teach vfs_ioc_fssetxattr_check to check extent size hints
  vfs: teach vfs_ioc_fssetxattr_check to check project id info
  vfs: create a generic checking function for FS_IOC_FSSETXATTR
  vfs: create a generic checking and prep function for FS_IOC_SETFLAGS
2019-07-12 16:54:37 -07:00
David Howells
4799974555 vfs: Convert efivarfs to use the new mount API
Convert the efivarfs filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

[AV: get rid of efivarfs_sb nonsense - it has never been used]

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Matthew Garrett <matthew.garrett@nebula.com>
cc: Jeremy Kerr <jk@ozlabs.org>
cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
cc: linux-efi@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-07-04 22:01:59 -04:00
Darrick J. Wong
5aca284210 vfs: create a generic checking and prep function for FS_IOC_SETFLAGS
Create a generic function to check incoming FS_IOC_SETFLAGS flag values
and later prepare the inode for updates so that we can standardize the
implementations that follow ext4's flag values.

Note that the efivarfs implementation no longer fails a no-op SETFLAGS
without CAP_LINUX_IMMUTABLE since that's the behavior in ext*.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
2019-07-01 08:25:34 -07:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
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>
2019-06-19 17:09:55 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Andy Shevchenko
c4326563d9 efivars: Call guid_parse() against guid_t type of variable
uuid_le_to_bin() is deprecated API and take into consideration that variable,
to where we store parsed data, is type of guid_t we switch to guid_parse()
for sake of consistency.

While here, add error checking to it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180720014726.24031-10-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-22 14:13:44 +02:00
Luck, Tony
bef3efbeb8 efivarfs: Limit the rate for non-root to read files
Each read from a file in efivarfs results in two calls to EFI
(one to get the file size, another to get the actual data).

On X86 these EFI calls result in broadcast system management
interrupts (SMI) which affect performance of the whole system.
A malicious user can loop performing reads from efivarfs bringing
the system to its knees.

Linus suggested per-user rate limit to solve this.

So we add a ratelimit structure to "user_struct" and initialize
it for the root user for no limit. When allocating user_struct for
other users we set the limit to 100 per second. This could be used
for other places that want to limit the rate of some detrimental
user action.

In efivarfs if the limit is exceeded when reading, we take an
interruptible nap for 50ms and check the rate limit again.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-22 10:21:02 -08:00
David Howells
1d278a8790 VFS: Kill off s_options and helpers
Kill off s_options, save/replace_mount_options() and generic_show_options()
as all filesystems now implement ->show_options() for themselves.  This
should make it easier to implement a context-based mount where the mount
options can be passed individually over a file descriptor.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-07-11 06:09:21 -04:00
Linus Torvalds
101105b171 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 ">rename2() work from Miklos + current_time() from Deepa"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Replace current_fs_time() with current_time()
  fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps
  fs: Replace CURRENT_TIME with current_time() for inode timestamps
  fs: proc: Delete inode time initializations in proc_alloc_inode()
  vfs: Add current_time() api
  vfs: add note about i_op->rename changes to porting
  fs: rename "rename2" i_op to "rename"
  vfs: remove unused i_op->rename
  fs: make remaining filesystems use .rename2
  libfs: support RENAME_NOREPLACE in simple_rename()
  fs: support RENAME_NOREPLACE for local filesystems
  ncpfs: fix unused variable warning
2016-10-10 20:16:43 -07:00
Deepa Dinamani
078cd8279e fs: Replace CURRENT_TIME with current_time() for inode timestamps
CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:06:21 -04:00
Matt Fleming
22c2b77f41 fs/efivarfs: Fix double kfree() in error path
Julia reported that we may double free 'name' in efivarfs_callback(),
and that this bug was introduced by commit 0d22f33bc37c ("efi: Don't
use spinlocks for efi vars").

Move one of the kfree()s until after the point at which we know we are
definitely on the success path.

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Sylvain Chouleur <sylvain.chouleur@gmail.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:48 +01:00
Sylvain Chouleur
21b3ddd39f efi: Don't use spinlocks for efi vars
All efivars operations are protected by a spinlock which prevents
interruptions and preemption. This is too restricted, we just need a
lock preventing concurrency.
The idea is to use a semaphore of count 1 and to have two ways of
locking, depending on the context:
- In interrupt context, we call down_trylock(), if it fails we return
  an error
- In normal context, we call down_interruptible()

We don't use a mutex here because the mutex_trylock() function must not
be called from interrupt context, whereas the down_trylock() can.

Signed-off-by: Sylvain Chouleur <sylvain.chouleur@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Sylvain Chouleur <sylvain.chouleur@gmail.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:42 +01:00
Al Viro
6fa67e7075 get rid of 'parent' argument of ->d_compare()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-31 16:37:25 -04:00
Linus Torvalds
8387ff2577 vfs: make the string hashes salt the hash
We always mixed in the parent pointer into the dentry name hash, but we
did it late at lookup time.  It turns out that we can simplify that
lookup-time action by salting the hash with the parent pointer early
instead of late.

A few other users of our string hashes also wanted to mix in their own
pointers into the hash, and those are updated to use the same mechanism.

Hash users that don't have any particular initial salt can just use the
NULL pointer as a no-salt.

Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-10 20:21:46 -07:00
Andy Shevchenko
8236431d8d fs/efivarfs/inode.c: use generic UUID library
Instead of opencoding let's use generic UUID library functions here.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 17:58:30 -07:00
Peter Jones
6c5450ef66 efivarfs: Make efivarfs_file_ioctl() static
There are no callers except through the file_operations struct below
this, so it should be static like everything else here.

Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1462570771-13324-6-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07 07:06:13 +02:00
Julia Lawall
1cfd63166c efi: Merge boolean flag arguments
The parameters atomic and duplicates of efivar_init always have opposite
values.  Drop the parameter atomic, replace the uses of !atomic with
duplicates, and update the call sites accordingly.

The code using duplicates is slightly reorganized with an 'else', to avoid
duplicating the lock code.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Saurabh Sengar <saurabh.truth@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1462570771-13324-5-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07 07:06:13 +02:00
Kirill A. Shutemov
09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Peter Jones
ed8b0de5a3 efi: Make efivarfs entries immutable by default
"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>
2016-02-10 16:25:52 +00:00
Peter Jones
e0d64e6a88 efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version
Translate EFI's UCS-2 variable names to UTF-8 instead of just assuming
all variable names fit in ASCII.

Signed-off-by: Peter Jones <pjones@redhat.com>
Acked-by: Matthew Garrett <mjg59@coreos.com>
Tested-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-02-10 13:19:14 +00:00