-----BEGIN PGP SIGNATURE-----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=NNLw
-----END PGP SIGNATURE-----
Merge tag 'selinux-pr-20201012' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux updates from Paul Moore:
"A decent number of SELinux patches for v5.10, twenty two in total. The
highlights are listed below, but all of the patches pass our test
suite and merge cleanly.
- A number of changes to how the SELinux policy is loaded and managed
inside the kernel with the goal of improving the atomicity of a
SELinux policy load operation.
These changes account for the bulk of the diffstat as well as the
patch count. A special thanks to everyone who contributed patches
and fixes for this work.
- Convert the SELinux policy read-write lock to RCU.
- A tracepoint was added for audited SELinux access control events;
this should help provide a more unified backtrace across kernel and
userspace.
- Allow the removal of security.selinux xattrs when a SELinux policy
is not loaded.
- Enable policy capabilities in SELinux policies created with the
scripts/selinux/mdp tool.
- Provide some "no sooner than" dates for the SELinux checkreqprot
sysfs deprecation"
* tag 'selinux-pr-20201012' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: (22 commits)
selinux: provide a "no sooner than" date for the checkreqprot removal
selinux: Add helper functions to get and set checkreqprot
selinux: access policycaps with READ_ONCE/WRITE_ONCE
selinux: simplify away security_policydb_len()
selinux: move policy mutex to selinux_state, use in lockdep checks
selinux: fix error handling bugs in security_load_policy()
selinux: convert policy read-write lock to RCU
selinux: delete repeated words in comments
selinux: add basic filtering for audit trace events
selinux: add tracepoint on audited events
selinux: Create new booleans and class dirs out of tree
selinux: Standardize string literal usage for selinuxfs directory names
selinux: Refactor selinuxfs directory populating functions
selinux: Create function for selinuxfs directory cleanup
selinux: permit removing security.selinux xattr before policy load
selinux: fix memdup.cocci warnings
selinux: avoid dereferencing the policy prior to initialization
selinux: fix allocation failure check on newpolicy->sidtab
selinux: refactor changing booleans
selinux: move policy commit after updating selinuxfs
...
Two kernel test robot suggested clean-ups.
Teach Smack to use the IPv4 netlabel cache.
This results in a 12-14% improvement on TCP benchmarks.
-----BEGIN PGP SIGNATURE-----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=EgBn
-----END PGP SIGNATURE-----
Merge tag 'Smack-for-5.10' of git://github.com/cschaufler/smack-next
Pull smack updates from Casey Schaufler:
"Two minor fixes and one performance enhancement to Smack. The
performance improvement is significant and the new code is more like
its counterpart in SELinux.
- Two kernel test robot suggested clean-ups.
- Teach Smack to use the IPv4 netlabel cache. This results in a
12-14% improvement on TCP benchmarks"
* tag 'Smack-for-5.10' of git://github.com/cschaufler/smack-next:
Smack: Remove unnecessary variable initialization
Smack: Fix build when NETWORK_SECMARK is not set
Smack: Use the netlabel cache
Smack: Set socket labels only once
Smack: Consolidate uses of secmark into a function
Pull crypto updates from Herbert Xu:
"API:
- Allow DRBG testing through user-space af_alg
- Add tcrypt speed testing support for keyed hashes
- Add type-safe init/exit hooks for ahash
Algorithms:
- Mark arc4 as obsolete and pending for future removal
- Mark anubis, khazad, sead and tea as obsolete
- Improve boot-time xor benchmark
- Add OSCCA SM2 asymmetric cipher algorithm and use it for integrity
Drivers:
- Fixes and enhancement for XTS in caam
- Add support for XIP8001B hwrng in xiphera-trng
- Add RNG and hash support in sun8i-ce/sun8i-ss
- Allow imx-rngc to be used by kernel entropy pool
- Use crypto engine in omap-sham
- Add support for Ingenic X1830 with ingenic"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (205 commits)
X.509: Fix modular build of public_key_sm2
crypto: xor - Remove unused variable count in do_xor_speed
X.509: fix error return value on the failed path
crypto: bcm - Verify GCM/CCM key length in setkey
crypto: qat - drop input parameter from adf_enable_aer()
crypto: qat - fix function parameters descriptions
crypto: atmel-tdes - use semicolons rather than commas to separate statements
crypto: drivers - use semicolons rather than commas to separate statements
hwrng: mxc-rnga - use semicolons rather than commas to separate statements
hwrng: iproc-rng200 - use semicolons rather than commas to separate statements
hwrng: stm32 - use semicolons rather than commas to separate statements
crypto: xor - use ktime for template benchmarking
crypto: xor - defer load time benchmark to a later time
crypto: hisilicon/zip - fix the uninitalized 'curr_qm_qp_num'
crypto: hisilicon/zip - fix the return value when device is busy
crypto: hisilicon/zip - fix zero length input in GZIP decompress
crypto: hisilicon/zip - fix the uncleared debug registers
lib/mpi: Fix unused variable warnings
crypto: x86/poly1305 - Remove assignments with no effect
hwrng: npcm - modify readl to readb
...
Pull compat iovec cleanups from Al Viro:
"Christoph's series around import_iovec() and compat variant thereof"
* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
security/keys: remove compat_keyctl_instantiate_key_iov
mm: remove compat_process_vm_{readv,writev}
fs: remove compat_sys_vmsplice
fs: remove the compat readv/writev syscalls
fs: remove various compat readv/writev helpers
iov_iter: transparently handle compat iovecs in import_iovec
iov_iter: refactor rw_copy_check_uvector and import_iovec
iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c
compat.h: fix a spelling error in <linux/compat.h>
- Preliminary RISC-V enablement - the bulk of it will arrive via the RISCV tree.
- Relax decompressed image placement rules for 32-bit ARM
- Add support for passing MOK certificate table contents via a config table
rather than a EFI variable.
- Add support for 18 bit DIMM row IDs in the CPER records.
- Work around broken Dell firmware that passes the entire Boot#### variable
contents as the command line
- Add definition of the EFI_MEMORY_CPU_CRYPTO memory attribute so we can
identify it in the memory map listings.
- Don't abort the boot on arm64 if the EFI RNG protocol is available but
returns with an error
- Replace slashes with exclamation marks in efivarfs file names
- Split efi-pstore from the deprecated efivars sysfs code, so we can
disable the latter on !x86.
- Misc fixes, cleanups and updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=ZNI8
-----END PGP SIGNATURE-----
Merge tag 'efi-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI changes from Ingo Molnar:
- Preliminary RISC-V enablement - the bulk of it will arrive via the
RISCV tree.
- Relax decompressed image placement rules for 32-bit ARM
- Add support for passing MOK certificate table contents via a config
table rather than a EFI variable.
- Add support for 18 bit DIMM row IDs in the CPER records.
- Work around broken Dell firmware that passes the entire Boot####
variable contents as the command line
- Add definition of the EFI_MEMORY_CPU_CRYPTO memory attribute so we
can identify it in the memory map listings.
- Don't abort the boot on arm64 if the EFI RNG protocol is available
but returns with an error
- Replace slashes with exclamation marks in efivarfs file names
- Split efi-pstore from the deprecated efivars sysfs code, so we can
disable the latter on !x86.
- Misc fixes, cleanups and updates.
* tag 'efi-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
efi: mokvar: add missing include of asm/early_ioremap.h
efi: efivars: limit availability to X86 builds
efi: remove some false dependencies on CONFIG_EFI_VARS
efi: gsmi: fix false dependency on CONFIG_EFI_VARS
efi: efivars: un-export efivars_sysfs_init()
efi: pstore: move workqueue handling out of efivars
efi: pstore: disentangle from deprecated efivars module
efi: mokvar-table: fix some issues in new code
efi/arm64: libstub: Deal gracefully with EFI_RNG_PROTOCOL failure
efivarfs: Replace invalid slashes with exclamation marks in dentries.
efi: Delete deprecated parameter comments
efi/libstub: Fix missing-prototypes in string.c
efi: Add definition of EFI_MEMORY_CPU_CRYPTO and ability to report it
cper,edac,efi: Memory Error Record: bank group/address and chip id
edac,ghes,cper: Add Row Extension to Memory Error Record
efi/x86: Add a quirk to support command line arguments on Dell EFI firmware
efi/libstub: Add efi_warn and *_once logging helpers
integrity: Load certs from the EFI MOK config table
integrity: Move import of MokListRT certs to a separate routine
efi: Support for MOK variable config table
...
Since commit e2dc9bf3f5 ("umd: Transform fork_usermode_blob into
fork_usermode_driver") started calling execve() on a program written in
a local mount which is not connected to mount tree,
tomoyo_realpath_from_path() started returning a pathname in
"$fsname:/$pathname" format which violates TOMOYO's domainname rule that
it must start with "<$namespace>" followed by zero or more repetitions of
pathnames which start with '/'.
Since $fsname must not contain '.' since commit 79c0b2df79 ("add
filesystem subtype support"), tomoyo_correct_path() can recognize a token
which appears '/' before '.' appears (e.g. proc:/self/exe ) as a pathname
while rejecting a token which appears '.' before '/' appears (e.g.
exec.realpath="/bin/bash" ) as a condition parameter.
Therefore, accept domainnames which contain pathnames which do not start
with '/' but contain '/' before '.' (e.g. <kernel> tmpfs:/bpfilter_umh ).
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
The initialization of rc in smack_from_netlbl() is pointless.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Now that import_iovec handles compat iovecs, the native version of
keyctl_instantiate_key_iov can be used for the compat case as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Use in compat_syscall to import either native or the compat iovecs, and
remove the now superflous compat_import_iovec.
This removes the need for special compat logic in most callers, and
the remaining ones can still be simplified by using __import_iovec
with a bool compat parameter.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Use proper conditional compilation for the secmark field in
the network skb.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Because of system-specific EFI firmware limitations, EFI volatile
variables may not be capable of holding the required contents of
the Machine Owner Key (MOK) certificate store when the certificate
list grows above some size. Therefore, an EFI boot loader may pass
the MOK certs via a EFI configuration table created specifically for
this purpose to avoid this firmware limitation.
An EFI configuration table is a much more primitive mechanism
compared to EFI variables and is well suited for one-way passage
of static information from a pre-OS environment to the kernel.
This patch adds the support to load certs from the MokListRT
entry in the MOK variable configuration table, if it's present.
The pre-existing support to load certs from the MokListRT EFI
variable remains and is used if the EFI MOK configuration table
isn't present or can't be successfully used.
Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Link: https://lore.kernel.org/r/20200905013107.10457-4-lszubowi@redhat.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Move the loading of certs from the UEFI MokListRT into a separate
routine to facilitate additional MokList functionality.
There is no visible functional change as a result of this patch.
Although the UEFI dbx certs are now loaded before the MokList certs,
they are loaded onto different key rings. So the order of the keys
on their respective key rings is the same.
Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Link: https://lore.kernel.org/r/20200905013107.10457-3-lszubowi@redhat.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
checkreqprot data member in selinux_state struct is accessed directly by
SELinux functions to get and set. This could cause unexpected read or
write access to this data member due to compiler optimizations and/or
compiler's reordering of access to this field.
Add helper functions to get and set checkreqprot data member in
selinux_state struct. These helper functions use READ_ONCE and
WRITE_ONCE macros to ensure atomic read or write of memory for
this data member.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Suggested-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Utilize the Netlabel cache mechanism for incoming packet matching.
Refactor the initialization of secattr structures, as it was being
done in two places.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Refactor the IP send checks so that the netlabel value
is set only when necessary, not on every send. Some functions
get renamed as the changes made the old name misleading.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Add a function smack_from_skb() that returns the Smack label
identified by a network secmark. Replace the explicit uses of
the secmark with this function.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Use READ_ONCE/WRITE_ONCE for all accesses to the
selinux_state.policycaps booleans to prevent compiler
mischief.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Remove the security_policydb_len() calls from sel_open_policy() and
instead update the inode size from the size returned from
security_read_policy().
Since after this change security_policydb_len() is only called from
security_load_policy(), remove it entirely and just open-code it there.
Also, since security_load_policy() is always called with policy_mutex
held, make it dereference the policy pointer directly and drop the
unnecessary RCU locking.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Move the mutex used to synchronize policy changes (reloads and setting
of booleans) from selinux_fs_info to selinux_state and use it in
lockdep checks for rcu_dereference_protected() calls in the security
server functions. This makes the dependency on the mutex explicit
in the code rather than relying on comments.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
There are a few bugs in the error handling for security_load_policy().
1) If the newpolicy->sidtab allocation fails then it leads to a NULL
dereference. Also the error code was not set to -ENOMEM on that
path.
2) If policydb_read() failed then we call policydb_destroy() twice
which meands we call kvfree(p->sym_val_to_name[i]) twice.
3) If policydb_load_isids() failed then we call sidtab_destroy() twice
and that results in a double free in the sidtab_destroy_tree()
function because entry.ptr_inner and entry.ptr_leaf are not set to
NULL.
One thing that makes this code nice to deal with is that none of the
functions return partially allocated data. In other words, the
policydb_read() either allocates everything successfully or it frees
all the data it allocates. It never returns a mix of allocated and
not allocated data.
I re-wrote this to only free the successfully allocated data which
avoids the double frees. I also re-ordered selinux_policy_free() so
it's in the reverse order of the allocation function.
Fixes: c7c556f1e8 ("selinux: refactor changing booleans")
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[PM: partially merged by hand due to merge fuzz]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Convert the policy read-write lock to RCU. This is significantly
simplified by the earlier work to encapsulate the policy data
structures and refactor the policy load and boolean setting logic.
Move the latest_granting sequence number into the selinux_policy
structure so that it can be updated atomically with the policy.
Since removing the policy rwlock and moving latest_granting reduces
the selinux_ss structure to nothing more than a wrapper around the
selinux_policy pointer, get rid of the extra layer of indirection.
At present this change merely passes a hardcoded 1 to
rcu_dereference_check() in the cases where we know we do not need to
take rcu_read_lock(), with the preceding comment explaining why.
Alternatively we could pass fsi->mutex down from selinuxfs and
apply a lockdep check on it instead.
Based in part on earlier attempts to convert the policy rwlock
to RCU by Kaigai Kohei [1] and by Peter Enderborg [2].
[1] https://lore.kernel.org/selinux/6e2f9128-e191-ebb3-0e87-74bfccb0767f@tycho.nsa.gov/
[2] https://lore.kernel.org/selinux/20180530141104.28569-1-peter.enderborg@sony.com/
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Drop a repeated word in comments.
{open, is, then}
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: selinux@vger.kernel.org
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-security-module@vger.kernel.org
[PM: fix subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
This patch adds further attributes to the event. These attributes are
helpful to understand the context of the message and can be used
to filter the events.
There are three common items. Source context, target context and tclass.
There are also items from the outcome of operation performed.
An event is similar to:
<...>-1309 [002] .... 6346.691689: selinux_audited:
requested=0x4000000 denied=0x4000000 audited=0x4000000
result=-13
scontext=system_u:system_r:cupsd_t:s0-s0:c0.c1023
tcontext=system_u:object_r:bin_t:s0 tclass=file
With systems where many denials are occurring, it is useful to apply a
filter. The filtering is a set of logic that is inserted with
the filter file. Example:
echo "tclass==\"file\" " > events/avc/selinux_audited/filter
This adds that we only get tclass=file.
The trace can also have extra properties. Adding the user stack
can be done with
echo 1 > options/userstacktrace
Now the output will be
runcon-1365 [003] .... 6960.955530: selinux_audited:
requested=0x4000000 denied=0x4000000 audited=0x4000000
result=-13
scontext=system_u:system_r:cupsd_t:s0-s0:c0.c1023
tcontext=system_u:object_r:bin_t:s0 tclass=file
runcon-1365 [003] .... 6960.955560: <user stack trace>
=> <00007f325b4ce45b>
=> <00005607093efa57>
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Reviewed-by: Thiébaud Weksteen <tweek@google.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The audit data currently captures which process and which target
is responsible for a denial. There is no data on where exactly in the
process that call occurred. Debugging can be made easier by being able to
reconstruct the unified kernel and userland stack traces [1]. Add a
tracepoint on the SELinux denials which can then be used by userland
(i.e. perf).
Although this patch could manually be added by each OS developer to
trouble shoot a denial, adding it to the kernel streamlines the
developers workflow.
It is possible to use perf for monitoring the event:
# perf record -e avc:selinux_audited -g -a
^C
# perf report -g
[...]
6.40% 6.40% audited=800000 tclass=4
|
__libc_start_main
|
|--4.60%--__GI___ioctl
| entry_SYSCALL_64
| do_syscall_64
| __x64_sys_ioctl
| ksys_ioctl
| binder_ioctl
| binder_set_nice
| can_nice
| capable
| security_capable
| cred_has_capability.isra.0
| slow_avc_audit
| common_lsm_audit
| avc_audit_post_callback
| avc_audit_post_callback
|
It is also possible to use the ftrace interface:
# echo 1 > /sys/kernel/debug/tracing/events/avc/selinux_audited/enable
# cat /sys/kernel/debug/tracing/trace
tracer: nop
entries-in-buffer/entries-written: 1/1 #P:8
[...]
dmesg-3624 [001] 13072.325358: selinux_denied: audited=800000 tclass=4
The tclass value can be mapped to a class by searching
security/selinux/flask.h. The audited value is a bit field of the
permissions described in security/selinux/av_permissions.h for the
corresponding class.
[1] https://source.android.com/devices/tech/debug/native_stack_dump
Signed-off-by: Thiébaud Weksteen <tweek@google.com>
Suggested-by: Joel Fernandes <joelaf@google.com>
Reviewed-by: Peter Enderborg <peter.enderborg@sony.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
In order to avoid concurrency issues around selinuxfs resource availability
during policy load, we first create new directories out of tree for
reloaded resources, then swap them in, and finally delete the old versions.
This fix focuses on concurrency in each of the two subtrees swapped, and
not concurrency between the trees. This means that it is still possible
that subsequent reads to eg the booleans directory and the class directory
during a policy load could see the old state for one and the new for the other.
The problem of ensuring that policy loads are fully atomic from the perspective
of userspace is larger than what is dealt with here. This commit focuses on
ensuring that the directories contents always match either the new or the old
policy state from the perspective of userspace.
In the previous implementation, on policy load /sys/fs/selinux is updated
by deleting the previous contents of
/sys/fs/selinux/{class,booleans} and then recreating them. This means
that there is a period of time when the contents of these directories do not
exist which can cause race conditions as userspace relies on them for
information about the policy. In addition, it means that error recovery in
the event of failure is challenging.
In order to demonstrate the race condition that this series fixes, you
can use the following commands:
while true; do cat /sys/fs/selinux/class/service/perms/status
>/dev/null; done &
while true; do load_policy; done;
In the existing code, this will display errors fairly often as the class
lookup fails. (In normal operation from systemd, this would result in a
permission check which would be allowed or denied based on policy settings
around unknown object classes.) After applying this patch series you
should expect to no longer see such error messages.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Switch class and policy_capabilities directory names to be referred to with
global constants, consistent with booleans directory name. This will allow
for easy consistency of naming in future development.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Make sel_make_bools and sel_make_classes take the specific elements of
selinux_fs_info that they need rather than the entire struct.
This will allow a future patch to pass temporary elements that are not in
the selinux_fs_info struct to these functions so that the original elements
can be preserved until we are ready to perform the switch over.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Separating the cleanup from the creation will simplify two things in
future patches in this series. First, the creation can be made generic,
to create directories not tied to the selinux_fs_info structure. Second,
we will ultimately want to reorder creation and deletion so that the
deletions aren't performed until the new directory structures have already
been moved into place.
Signed-off-by: Daniel Burgener <dburgener@linux.microsoft.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Currently SELinux denies attempts to remove the security.selinux xattr
always, even when permissive or no policy is loaded. This was originally
motivated by the view that all files should be labeled, even if that label
is unlabeled_t, and we shouldn't permit files that were once labeled to
have their labels removed entirely. This however prevents removing
SELinux xattrs in the case where one "disables" SELinux by not loading
a policy (e.g. a system where runtime disable is removed and selinux=0
was not specified). Allow removing the xattr before SELinux is
initialized. We could conceivably permit it even after initialization
if permissive, or introduce a separate permission check here.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
exceptions may be traversed using list_for_each_entry_rcu()
outside of an RCU read side critical section BUT under the
protection of decgroup_mutex. Hence add the corresponding
lockdep expression to fix the following false-positive
warning:
[ 2.304417] =============================
[ 2.304418] WARNING: suspicious RCU usage
[ 2.304420] 5.5.4-stable #17 Tainted: G E
[ 2.304422] -----------------------------
[ 2.304424] security/device_cgroup.c:355 RCU-list traversed in non-reader section!!
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
Use kmemdup rather than duplicating its implementation
Generated by: scripts/coccinelle/api/memdup.cocci
Fixes: c7c556f1e8 ("selinux: refactor changing booleans")
CC: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Certain SELinux security server functions (e.g. security_port_sid,
called during bind) were not explicitly testing to see if SELinux
has been initialized (i.e. initial policy loaded) and handling
the no-policy-loaded case. In the past this happened to work
because the policydb was statically allocated and could always
be accessed, but with the recent encapsulation of policy state
and conversion to dynamic allocation, we can no longer access
the policy state prior to initialization. Add a test of
!selinux_initialized(state) to all of the exported functions that
were missing them and handle appropriately.
Fixes: 461698026f ("selinux: encapsulate policy state, refactor policy load")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The allocation check of newpolicy->sidtab is null checking if
newpolicy is null and not newpolicy->sidtab. Fix this.
Addresses-Coverity: ("Logically dead code")
Fixes: c7c556f1e8 ("selinux: refactor changing booleans")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Refactor the logic for changing SELinux policy booleans in a similar
manner to the refactoring of policy load, thereby reducing the
size of the critical section when the policy write-lock is held
and making it easier to convert the policy rwlock to RCU in the
future. Instead of directly modifying the policydb in place, modify
a copy and then swap it into place through a single pointer update.
Only fully copy the portions of the policydb that are affected by
boolean changes to avoid the full cost of a deep policydb copy.
Introduce another level of indirection for the sidtab since changing
booleans does not require updating the sidtab, unlike policy load.
While we are here, create a common helper for notifying
other kernel components and userspace of a policy change and call it
from both security_set_bools() and selinux_policy_commit().
Based on an old (2004) patch by Kaigai Kohei [1] to convert the policy
rwlock to RCU that was deferred at the time since it did not
significantly improve performance and introduced complexity. Peter
Enderborg later submitted a patch series to convert to RCU [2] that
would have made changing booleans a much more expensive operation
by requiring a full policydb_write();policydb_read(); sequence to
deep copy the entire policydb and also had concerns regarding
atomic allocations.
This change is now simplified by the earlier work to encapsulate
policy state in the selinux_policy struct and to refactor
policy load. After this change, the last major obstacle to
converting the policy rwlock to RCU is likely the sidtab live
convert support.
[1] https://lore.kernel.org/selinux/6e2f9128-e191-ebb3-0e87-74bfccb0767f@tycho.nsa.gov/
[2] https://lore.kernel.org/selinux/20180530141104.28569-1-peter.enderborg@sony.com/
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
With the refactoring of the policy load logic in the security
server from the previous change, it is now possible to split out
the committing of the new policy from security_load_policy() and
perform it only after successful updating of selinuxfs. Change
security_load_policy() to return the newly populated policy
data structures to the caller, export selinux_policy_commit()
for external callers, and introduce selinux_policy_cancel() to
provide a way to cancel the policy load in the event of an error
during updating of the selinuxfs directory tree. Further, rework
the interfaces used by selinuxfs to get information from the policy
when creating the new directory tree to take and act upon the
new policy data structure rather than the current/active policy.
Update selinuxfs to use these updated and new interfaces. While
we are here, stop re-creating the policy_capabilities directory
on each policy load since it does not depend on the policy, and
stop trying to create the booleans and classes directories during
the initial creation of selinuxfs since no information is available
until first policy load.
After this change, a failure while updating the booleans and class
directories will cause the entire policy load to be canceled, leaving
the original policy intact, and policy load notifications to userspace
will only happen after a successful completion of updating those
directories. This does not (yet) provide full atomicity with respect
to the updating of the directory trees themselves.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Encapsulate the policy state in its own structure (struct
selinux_policy) that is separately allocated but referenced from the
selinux_ss structure. The policy state includes the SID table
(particularly the context structures), the policy database, and the
mapping between the kernel classes/permissions and the policy values.
Refactor the security server portion of the policy load logic to
cleanly separate loading of the new structures from committing the new
policy. Unify the initial policy load and reload code paths as much
as possible, avoiding duplicated code. Make sure we are taking the
policy read-lock prior to any dereferencing of the policy. Move the
copying of the policy capability booleans into the state structure
outside of the policy write-lock because they are separate from the
policy and are read outside of any policy lock; possibly they should
be using at least READ_ONCE/WRITE_ONCE or smp_load_acquire/store_release.
These changes simplify the policy loading logic, reduce the size of
the critical section while holding the policy write-lock, and should
facilitate future changes to e.g. refactor the entire policy reload
logic including the selinuxfs code to make the updating of the policy
and the selinuxfs directory tree atomic and/or to convert the policy
read-write lock to RCU.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Presently mdp does not enable any SELinux policy capabilities
in the dummy policy it generates. Thus, policies derived from
it will by default lack various features commonly used in modern
policies such as open permission, extended socket classes, network
peer controls, etc. Split the policy capability definitions out into
their own headers so that we can include them into mdp without pulling in
other kernel headers and extend mdp generate policycap statements for the
policy capabilities known to the kernel. Policy authors may wish to
selectively remove some of these from the generated policy.
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Merge more updates from Andrew Morton:
- most of the rest of MM (memcg, hugetlb, vmscan, proc, compaction,
mempolicy, oom-kill, hugetlbfs, migration, thp, cma, util,
memory-hotplug, cleanups, uaccess, migration, gup, pagemap),
- various other subsystems (alpha, misc, sparse, bitmap, lib, bitops,
checkpatch, autofs, minix, nilfs, ufs, fat, signals, kmod, coredump,
exec, kdump, rapidio, panic, kcov, kgdb, ipc).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (164 commits)
mm/gup: remove task_struct pointer for all gup code
mm: clean up the last pieces of page fault accountings
mm/xtensa: use general page fault accounting
mm/x86: use general page fault accounting
mm/sparc64: use general page fault accounting
mm/sparc32: use general page fault accounting
mm/sh: use general page fault accounting
mm/s390: use general page fault accounting
mm/riscv: use general page fault accounting
mm/powerpc: use general page fault accounting
mm/parisc: use general page fault accounting
mm/openrisc: use general page fault accounting
mm/nios2: use general page fault accounting
mm/nds32: use general page fault accounting
mm/mips: use general page fault accounting
mm/microblaze: use general page fault accounting
mm/m68k: use general page fault accounting
mm/ia64: use general page fault accounting
mm/hexagon: use general page fault accounting
mm/csky: use general page fault accounting
...
After the cleanup of page fault accounting, gup does not need to pass
task_struct around any more. Remove that parameter in the whole gup
stack.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----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=s2Jw
-----END PGP SIGNATURE-----
Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"A couple of minor documentation updates only for this release"
* tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
LSM: drop duplicated words in header file comments
Replace HTTP links with HTTPS ones: security
As said by Linus:
A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.
In "kzalloc()", the z is meaningful and an important part of what the
caller wants.
In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.
The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.
Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.
The renaming is done by using the command sequence:
git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'
followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.
[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
-----BEGIN PGP SIGNATURE-----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=M/tq
-----END PGP SIGNATURE-----
Merge tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"The nicest change is the IMA policy rule checking. The other changes
include allowing the kexec boot cmdline line measure policy rules to
be defined in terms of the inode associated with the kexec kernel
image, making the IMA_APPRAISE_BOOTPARAM, which governs the IMA
appraise mode (log, fix, enforce), a runtime decision based on the
secure boot mode of the system, and including errno in the audit log"
* tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
integrity: remove redundant initialization of variable ret
ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtime
ima: AppArmor satisfies the audit rule requirements
ima: Rename internal filter rule functions
ima: Support additional conditionals in the KEXEC_CMDLINE hook function
ima: Use the common function to detect LSM conditionals in a rule
ima: Move comprehensive rule validation checks out of the token parser
ima: Use correct type for the args_p member of ima_rule_entry.lsm elements
ima: Shallow copy the args_p member of ima_rule_entry.lsm elements
ima: Fail rule parsing when appraise_flag=blacklist is unsupportable
ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond
ima: Fail rule parsing when the KEXEC_CMDLINE hook is combined with an invalid cond
ima: Fail rule parsing when buffer hook functions have an invalid action
ima: Free the entire rule if it fails to parse
ima: Free the entire rule when deleting a list of rules
ima: Have the LSM free its audit rule
IMA: Add audit log for failure conditions
integrity: Add errno field in audit message
-----BEGIN PGP SIGNATURE-----
iQJLBAABCAA1FiEEC+9tH1YyUwIQzUIeOKUVfIxDyBEFAl8pmVMXHGNhc2V5QHNj
aGF1Zmxlci1jYS5jb20ACgkQOKUVfIxDyBE4tA/7BvMGZjrGVu7F8oOJGam6xiQ+
iVczarvuH9HUfIWWKytgAZXaNf8/lQvpTGYjJFdLGVaLVfB4CSrrrdOGlfvZGpZ/
5CXeSMAAUOAmYnqjSXFuLqp0NJEEwBg0L7/YWGbp/fq7t8WcY73esDRpVw/R78fV
rOSMq+qt+IKRERUZWHa3gY7/FDA1/KnEkXjcMViM9PN3Gi5u2Fw6IMVWugPYJYrh
86jlrDxYV3ceqDpoiHGyulMcBk/f/GppjIWz4ihZ0YShn+ZgAXsnJGjEhGxsoSXb
CdG0O0y/m6y/+ekyovhvL8+AymfVWbK3qzE8IxWp8Xbrd882naur0c0vTG6y2eF7
Z2HnI3ivusNrKTkXQnzC86YJ0T96Pg9OCab5poSIsWK5bM542dKZ/7KoSDfzIfBH
uPhTY2PyRSiUiCWpt7esHtp4mYwCGqUs2j80TZDb8ptAZbYKxzC0pFIDoFeEyOM4
FDBXjH8Bo+eEG9V8OgGeVvluYaat+C00dba9fiOT7/Tm0F9KqOJEOO9uJPV9CuJN
+jrL90mopy8T0bygqMjp+GB5V13IGL5+NDHZcnO3Ij5jI/7q0TQ6FlFZ4tg4o4yM
Y7FyMF+ybUlRod0ayYgurtxn91c0E/PTOPSqtL/RKtRLbLdGrOM3Rfbxn9rREONY
h1/RmmX5jSBQOKNq9/Y=
=ZoLN
-----END PGP SIGNATURE-----
Merge tag 'Smack-for-5.9' of git://github.com/cschaufler/smack-next
Pull smack updates from Casey Schaufler:
"Minor fixes to Smack for the v5.9 release.
All were found by automated checkers and have straightforward
resolution"
* tag 'Smack-for-5.9' of git://github.com/cschaufler/smack-next:
Smack: prevent underflow in smk_set_cipso()
Smack: fix another vsscanf out of bounds
Smack: fix use-after-free in smk_write_relabel_self()
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXygegQAKCRCRxhvAZXjc
olWZAQCMPbhI/20LA3OYJ6s+BgBEnm89PymvlHcym6Z4AvTungD+KqZonIYuxWgi
6Ttlv/fzgFFbXgJgbuass5mwFVoN5wM=
=oK7d
-----END PGP SIGNATURE-----
Merge tag 'cap-checkpoint-restore-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull checkpoint-restore updates from Christian Brauner:
"This enables unprivileged checkpoint/restore of processes.
Given that this work has been going on for quite some time the first
sentence in this summary is hopefully more exciting than the actual
final code changes required. Unprivileged checkpoint/restore has seen
a frequent increase in interest over the last two years and has thus
been one of the main topics for the combined containers &
checkpoint/restore microconference since at least 2018 (cf. [1]).
Here are just the three most frequent use-cases that were brought forward:
- The JVM developers are integrating checkpoint/restore into a Java
VM to significantly decrease the startup time.
- In high-performance computing environment a resource manager will
typically be distributing jobs where users are always running as
non-root. Long-running and "large" processes with significant
startup times are supposed to be checkpointed and restored with
CRIU.
- Container migration as a non-root user.
In all of these scenarios it is either desirable or required to run
without CAP_SYS_ADMIN. The userspace implementation of
checkpoint/restore CRIU already has the pull request for supporting
unprivileged checkpoint/restore up (cf. [2]).
To enable unprivileged checkpoint/restore a new dedicated capability
CAP_CHECKPOINT_RESTORE is introduced. This solution has last been
discussed in 2019 in a talk by Google at Linux Plumbers (cf. [1]
"Update on Task Migration at Google Using CRIU") with Adrian and
Nicolas providing the implementation now over the last months. In
essence, this allows the CRIU binary to be installed with the
CAP_CHECKPOINT_RESTORE vfs capability set thereby enabling
unprivileged users to restore processes.
To make this possible the following permissions are altered:
- Selecting a specific PID via clone3() set_tid relaxed from userns
CAP_SYS_ADMIN to CAP_CHECKPOINT_RESTORE.
- Selecting a specific PID via /proc/sys/kernel/ns_last_pid relaxed
from userns CAP_SYS_ADMIN to CAP_CHECKPOINT_RESTORE.
- Accessing /proc/pid/map_files relaxed from init userns
CAP_SYS_ADMIN to init userns CAP_CHECKPOINT_RESTORE.
- Changing /proc/self/exe from userns CAP_SYS_ADMIN to userns
CAP_CHECKPOINT_RESTORE.
Of these four changes the /proc/self/exe change deserves a few words
because the reasoning behind even restricting /proc/self/exe changes
in the first place is just full of historical quirks and tracking this
down was a questionable version of fun that I'd like to spare others.
In short, it is trivial to change /proc/self/exe as an unprivileged
user, i.e. without userns CAP_SYS_ADMIN right now. Either via ptrace()
or by simply intercepting the elf loader in userspace during exec.
Nicolas was nice enough to even provide a POC for the latter (cf. [3])
to illustrate this fact.
The original patchset which introduced PR_SET_MM_MAP had no
permissions around changing the exe link. They too argued that it is
trivial to spoof the exe link already which is true. The argument
brought up against this was that the Tomoyo LSM uses the exe link in
tomoyo_manager() to detect whether the calling process is a policy
manager. This caused changing the exe links to be guarded by userns
CAP_SYS_ADMIN.
All in all this rather seems like a "better guard it with something
rather than nothing" argument which imho doesn't qualify as a great
security policy. Again, because spoofing the exe link is possible for
the calling process so even if this were security relevant it was
broken back then and would be broken today. So technically, dropping
all permissions around changing the exe link would probably be
possible and would send a clearer message to any userspace that relies
on /proc/self/exe for security reasons that they should stop doing
this but for now we're only relaxing the exe link permissions from
userns CAP_SYS_ADMIN to userns CAP_CHECKPOINT_RESTORE.
There's a final uapi change in here. Changing the exe link used to
accidently return EINVAL when the caller lacked the necessary
permissions instead of the more correct EPERM. This pr contains a
commit fixing this. I assume that userspace won't notice or care and
if they do I will revert this commit. But since we are changing the
permissions anyway it seems like a good opportunity to try this fix.
With these changes merged unprivileged checkpoint/restore will be
possible and has already been tested by various users"
[1] LPC 2018
1. "Task Migration at Google Using CRIU"
https://www.youtube.com/watch?v=yI_1cuhoDgA&t=12095
2. "Securely Migrating Untrusted Workloads with CRIU"
https://www.youtube.com/watch?v=yI_1cuhoDgA&t=14400
LPC 2019
1. "CRIU and the PID dance"
https://www.youtube.com/watch?v=LN2CUgp8deo&list=PLVsQ_xZBEyN30ZA3Pc9MZMFzdjwyz26dO&index=9&t=2m48s
2. "Update on Task Migration at Google Using CRIU"
https://www.youtube.com/watch?v=LN2CUgp8deo&list=PLVsQ_xZBEyN30ZA3Pc9MZMFzdjwyz26dO&index=9&t=1h2m8s
[2] https://github.com/checkpoint-restore/criu/pull/1155
[3] https://github.com/nviennot/run_as_exe
* tag 'cap-checkpoint-restore-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests: add clone3() CAP_CHECKPOINT_RESTORE test
prctl: exe link permission error changed from -EINVAL to -EPERM
prctl: Allow local CAP_CHECKPOINT_RESTORE to change /proc/self/exe
proc: allow access in init userns for map_files with CAP_CHECKPOINT_RESTORE
pid_namespace: use checkpoint_restore_ns_capable() for ns_last_pid
pid: use checkpoint_restore_ns_capable() for set_tid
capabilities: Introduce CAP_CHECKPOINT_RESTORE
Pull execve updates from Eric Biederman:
"During the development of v5.7 I ran into bugs and quality of
implementation issues related to exec that could not be easily fixed
because of the way exec is implemented. So I have been diggin into
exec and cleaning up what I can.
This cycle I have been looking at different ideas and different
implementations to see what is possible to improve exec, and cleaning
the way exec interfaces with in kernel users. Only cleaning up the
interfaces of exec with rest of the kernel has managed to stabalize
and make it through review in time for v5.9-rc1 resulting in 2 sets of
changes this cycle.
- Implement kernel_execve
- Make the user mode driver code a better citizen
With kernel_execve the code size got a little larger as the copying of
parameters from userspace and copying of parameters from userspace is
now separate. The good news is kernel threads no longer need to play
games with set_fs to use exec. Which when combined with the rest of
Christophs set_fs changes should security bugs with set_fs much more
difficult"
* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits)
exec: Implement kernel_execve
exec: Factor bprm_stack_limits out of prepare_arg_pages
exec: Factor bprm_execve out of do_execve_common
exec: Move bprm_mm_init into alloc_bprm
exec: Move initialization of bprm->filename into alloc_bprm
exec: Factor out alloc_bprm
exec: Remove unnecessary spaces from binfmts.h
umd: Stop using split_argv
umd: Remove exit_umh
bpfilter: Take advantage of the facilities of struct pid
exit: Factor thread_group_exited out of pidfd_poll
umd: Track user space drivers with struct pid
bpfilter: Move bpfilter_umh back into init data
exec: Remove do_execve_file
umh: Stop calling do_execve_file
umd: Transform fork_usermode_blob into fork_usermode_driver
umd: Rename umd_info.cmdline umd_info.driver_name
umd: For clarity rename umh_info umd_info
umh: Separate the user mode driver and the user mode helper support
umh: Remove call_usermodehelper_setup_file.
...
