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>
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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
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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()
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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.
...
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Merge tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"Aside from some smaller bug fixes, here are the highlights:
- add a new backlog wait metric to the audit status message, this is
intended to help admins determine how long processes have been
waiting for the audit backlog queue to clear
- generate audit records for nftables configuration changes
- generate CWD audit records for for the relevant LSM audit records"
* tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: report audit wait metric in audit status reply
audit: purge audit_log_string from the intra-kernel audit API
audit: issue CWD record to accompany LSM_AUDIT_DATA_* records
audit: use the proper gfp flags in the audit_log_nfcfg() calls
audit: remove unused !CONFIG_AUDITSYSCALL __audit_inode* stubs
audit: add gfp parameter to audit_log_nfcfg
audit: log nftables configuration change events
audit: Use struct_size() helper in alloc_chunk
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Merge tag 'selinux-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux updates from Paul Moore:
"Beyond the usual smattering of bug fixes, we've got three small
improvements worth highlighting:
- improved SELinux policy symbol table performance due to a reworking
of the insert and search functions
- allow reading of SELinux labels before the policy is loaded,
allowing for some more "exotic" initramfs approaches
- improved checking an error reporting about process
class/permissions during SELinux policy load"
* tag 'selinux-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: complete the inlining of hashtab functions
selinux: prepare for inlining of hashtab functions
selinux: specialize symtab insert and search functions
selinux: Fix spelling mistakes in the comments
selinux: fixed a checkpatch warning with the sizeof macro
selinux: log error messages on required process class / permissions
scripts/selinux/mdp: fix initial SID handling
selinux: allow reading labels before policy is loaded
- Introduce CONFIG_INIT_STACK_ALL_ZERO (Alexander Potapenko)
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Merge tag 'var-init-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull automatic variable initialization updates from Kees Cook:
"This adds the "zero" init option from Clang, which is being used
widely in production builds of Android and Chrome OS (though it also
keeps the "pattern" init, which is better for debug builds).
- Introduce CONFIG_INIT_STACK_ALL_ZERO (Alexander Potapenko)"
* tag 'var-init-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
security: allow using Clang's zero initialization for stack variables
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Merge tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
"Good amount of cleanups and tech debt removals in here, and as a
result, the diffstat shows a nice net reduction in code.
- Softirq completion cleanups (Christoph)
- Stop using ->queuedata (Christoph)
- Cleanup bd claiming (Christoph)
- Use check_events, moving away from the legacy media change
(Christoph)
- Use inode i_blkbits consistently (Christoph)
- Remove old unused writeback congestion bits (Christoph)
- Cleanup/unify submission path (Christoph)
- Use bio_uninit consistently, instead of bio_disassociate_blkg
(Christoph)
- sbitmap cleared bits handling (John)
- Request merging blktrace event addition (Jan)
- sysfs add/remove race fixes (Luis)
- blk-mq tag fixes/optimizations (Ming)
- Duplicate words in comments (Randy)
- Flush deferral cleanup (Yufen)
- IO context locking/retry fixes (John)
- struct_size() usage (Gustavo)
- blk-iocost fixes (Chengming)
- blk-cgroup IO stats fixes (Boris)
- Various little fixes"
* tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block: (135 commits)
block: blk-timeout: delete duplicated word
block: blk-mq-sched: delete duplicated word
block: blk-mq: delete duplicated word
block: genhd: delete duplicated words
block: elevator: delete duplicated word and fix typos
block: bio: delete duplicated words
block: bfq-iosched: fix duplicated word
iocost_monitor: start from the oldest usage index
iocost: Fix check condition of iocg abs_vdebt
block: Remove callback typedefs for blk_mq_ops
block: Use non _rcu version of list functions for tag_set_list
blk-cgroup: show global disk stats in root cgroup io.stat
blk-cgroup: make iostat functions visible to stat printing
block: improve discard bio alignment in __blkdev_issue_discard()
block: change REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL to be odd numbers
block: defer flush request no matter whether we have elevator
block: make blk_timeout_init() static
block: remove retry loop in ioc_release_fn()
block: remove unnecessary ioc nested locking
block: integrate bd_start_claiming into __blkdev_get
...
The variable ret is being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.
Fixes: eb5798f2e2 ("integrity: convert digsig to akcipher api")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Addresses-Coverity: ("Unused value")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
We have an upper bound on "maplevel" but forgot to check for negative
values.
Fixes: e114e47377 ("Smack: Simplified Mandatory Access Control Kernel")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
This is similar to commit 84e99e58e8 ("Smack: slab-out-of-bounds in
vsscanf") where we added a bounds check on "rule".
Reported-by: syzbot+a22c6092d003d6fe1122@syzkaller.appspotmail.com
Fixes: f7112e6c9a ("Smack: allow for significantly longer Smack labels v4")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
audit_log_string() was inteded to be an internal audit function and
since there are only two internal uses, remove them. Purge all external
uses of it by restructuring code to use an existing audit_log_format()
or using audit_log_format().
Please see the upstream issue
https://github.com/linux-audit/audit-kernel/issues/84
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
To allow the kernel not to play games with set_fs to call exec
implement kernel_execve. The function kernel_execve takes pointers
into kernel memory and copies the values pointed to onto the new
userspace stack.
The calls with arguments from kernel space of do_execve are replaced
with calls to kernel_execve.
The calls do_execve and do_execveat are made static as there are now
no callers outside of exec.
The comments that mention do_execve are updated to refer to
kernel_execve or execve depending on the circumstances. In addition
to correcting the comments, this makes it easy to grep for do_execve
and verify it is not used.
Inspired-by: https://lkml.kernel.org/r/20200627072704.2447163-1-hch@lst.de
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/87wo365ikj.fsf@x220.int.ebiederm.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The IMA_APPRAISE_BOOTPARAM config allows enabling different "ima_appraise="
modes - log, fix, enforce - at run time, but not when IMA architecture
specific policies are enabled. This prevents properly labeling the
filesystem on systems where secure boot is supported, but not enabled on the
platform. Only when secure boot is actually enabled should these IMA
appraise modes be disabled.
This patch removes the compile time dependency and makes it a runtime
decision, based on the secure boot state of that platform.
Test results as follows:
-> x86-64 with secure boot enabled
[ 0.015637] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix
[ 0.015668] ima: Secure boot enabled: ignoring ima_appraise=fix boot parameter option
-> powerpc with secure boot disabled
[ 0.000000] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix
[ 0.000000] Secure boot mode disabled
-> Running the system without secure boot and with both options set:
CONFIG_IMA_APPRAISE_BOOTPARAM=y
CONFIG_IMA_ARCH_POLICY=y
Audit prompts "missing-hash" but still allow execution and, consequently,
filesystem labeling:
type=INTEGRITY_DATA msg=audit(07/09/2020 12:30:27.778:1691) : pid=4976
uid=root auid=root ses=2
subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 op=appraise_data
cause=missing-hash comm=bash name=/usr/bin/evmctl dev="dm-0" ino=493150
res=no
Cc: stable@vger.kernel.org
Fixes: d958083a8f ("x86/ima: define arch_get_ima_policy() for x86")
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Cc: stable@vger.kernel.org # 5.0
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
AppArmor meets all the requirements for IMA in terms of audit rules
since commit e79c26d040 ("apparmor: Add support for audit rule
filtering"). Update IMA's Kconfig section for CONFIG_IMA_LSM_RULES to
reflect this.
Fixes: e79c26d040 ("apparmor: Add support for audit rule filtering")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Rename IMA's internal filter rule functions from security_filter_rule_*()
to ima_filter_rule_*(). This avoids polluting the security_* namespace,
which is typically reserved for general security subsystem
infrastructure.
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Suggested-by: Casey Schaufler <casey@schaufler-ca.com>
[zohar@linux.ibm.com: reword using the term "filter", not "audit"]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Take the properties of the kexec kernel's inode and the current task
ownership into consideration when matching a KEXEC_CMDLINE operation to
the rules in the IMA policy. This allows for some uniformity when
writing IMA policy rules for KEXEC_KERNEL_CHECK, KEXEC_INITRAMFS_CHECK,
and KEXEC_CMDLINE operations.
Prior to this patch, it was not possible to write a set of rules like
this:
dont_measure func=KEXEC_KERNEL_CHECK obj_type=foo_t
dont_measure func=KEXEC_INITRAMFS_CHECK obj_type=foo_t
dont_measure func=KEXEC_CMDLINE obj_type=foo_t
measure func=KEXEC_KERNEL_CHECK
measure func=KEXEC_INITRAMFS_CHECK
measure func=KEXEC_CMDLINE
The inode information associated with the kernel being loaded by a
kexec_kernel_load(2) syscall can now be included in the decision to
measure or not
Additonally, the uid, euid, and subj_* conditionals can also now be
used in KEXEC_CMDLINE rules. There was no technical reason as to why
those conditionals weren't being considered previously other than
ima_match_rules() didn't have a valid inode to use so it immediately
bailed out for KEXEC_CMDLINE operations rather than going through the
full list of conditional comparisons.
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Make broader use of ima_rule_contains_lsm_cond() to check if a given
rule contains an LSM conditional. This is a code cleanup and has no
user-facing change.
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Use ima_validate_rule(), at the end of the token parsing stage, to
verify combinations of actions, hooks, and flags. This is useful to
increase readability by consolidating such checks into a single function
and also because rule conditionals can be specified in arbitrary order
making it difficult to do comprehensive rule validation until the entire
rule has been parsed.
This allows for the check that ties together the "keyrings" conditional
with the KEY_CHECK function hook to be moved into the final rule
validation.
The modsig check no longer needs to compiled conditionally because the
token parser will ensure that modsig support is enabled before accepting
"imasig|modsig" appraise type values. The final rule validation will
ensure that appraise_type and appraise_flag options are only present in
appraise rules.
Finally, this allows for the check that ties together the "pcr"
conditional with the measure action to be moved into the final rule
validation.
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Make args_p be of the char pointer type rather than have it be a void
pointer that gets casted to char pointer when it is used. It is a simple
NUL-terminated string as returned by match_strdup().
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
The args_p member is a simple string that is allocated by
ima_rule_init(). Shallow copy it like other non-LSM references in
ima_rule_entry structs.
There are no longer any necessary error path cleanups to do in
ima_lsm_copy_rule().
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Verifying that a file hash is not blacklisted is currently only
supported for files with appended signatures (modsig). In the future,
this might change.
For now, the "appraise_flag" option is only appropriate for appraise
actions and its "blacklist" value is only appropriate when
CONFIG_IMA_APPRAISE_MODSIG is enabled and "appraise_flag=blacklist" is
only appropriate when "appraise_type=imasig|modsig" is also present.
Make this clear at policy load so that IMA policy authors don't assume
that other uses of "appraise_flag=blacklist" are supported.
Fixes: 273df864cf ("ima: Check against blacklisted hashes for files with modsig")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reivewed-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
This patch introduces CAP_CHECKPOINT_RESTORE, a new capability facilitating
checkpoint/restore for non-root users.
Over the last years, The CRIU (Checkpoint/Restore In Userspace) team has
been asked numerous times if it is possible to checkpoint/restore a
process as non-root. The answer usually was: 'almost'.
The main blocker to restore a process as non-root was to control the PID
of the restored process. This feature available via the clone3 system
call, or via /proc/sys/kernel/ns_last_pid is unfortunately guarded by
CAP_SYS_ADMIN.
In the past two years, requests for non-root checkpoint/restore have
increased due to the following use cases:
* Checkpoint/Restore in an HPC environment in combination with a
resource manager distributing jobs where users are always running as
non-root. There is a desire to provide a way to checkpoint and
restore long running jobs.
* Container migration as non-root
* We have been in contact with JVM developers who are integrating
CRIU into a Java VM to decrease the startup time. These
checkpoint/restore applications are not meant to be running with
CAP_SYS_ADMIN.
We have seen the following workarounds:
* Use a setuid wrapper around CRIU:
See https://github.com/FredHutch/slurm-examples/blob/master/checkpointer/lib/checkpointer/checkpointer-suid.c
* Use a setuid helper that writes to ns_last_pid.
Unfortunately, this helper delegation technique is impossible to use
with clone3, and is thus prone to races.
See https://github.com/twosigma/set_ns_last_pid
* Cycle through PIDs with fork() until the desired PID is reached:
This has been demonstrated to work with cycling rates of 100,000 PIDs/s
See https://github.com/twosigma/set_ns_last_pid
* Patch out the CAP_SYS_ADMIN check from the kernel
* Run the desired application in a new user and PID namespace to provide
a local CAP_SYS_ADMIN for controlling PIDs. This technique has limited
use in typical container environments (e.g., Kubernetes) as /proc is
typically protected with read-only layers (e.g., /proc/sys) for
hardening purposes. Read-only layers prevent additional /proc mounts
(due to proc's SB_I_USERNS_VISIBLE property), making the use of new
PID namespaces limited as certain applications need access to /proc
matching their PID namespace.
The introduced capability allows to:
* Control PIDs when the current user is CAP_CHECKPOINT_RESTORE capable
for the corresponding PID namespace via ns_last_pid/clone3.
* Open files in /proc/pid/map_files when the current user is
CAP_CHECKPOINT_RESTORE capable in the root namespace, useful for
recovering files that are unreachable via the file system such as
deleted files, or memfd files.
See corresponding selftest for an example with clone3().
Signed-off-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Nicolas Viennot <Nicolas.Viennot@twosigma.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200719100418.2112740-2-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The KEY_CHECK function only supports the uid, pcr, and keyrings
conditionals. Make this clear at policy load so that IMA policy authors
don't assume that other conditionals are supported.
Fixes: 5808611ccc ("IMA: Add KEY_CHECK func to measure keys")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
The KEXEC_CMDLINE hook function only supports the pcr conditional. Make
this clear at policy load so that IMA policy authors don't assume that
other conditionals are supported.
Since KEXEC_CMDLINE's inception, ima_match_rules() has always returned
true on any loaded KEXEC_CMDLINE rule without any consideration for
other conditionals present in the rule. Make it clear that pcr is the
only supported KEXEC_CMDLINE conditional by returning an error during
policy load.
An example of why this is a problem can be explained with the following
rule:
dont_measure func=KEXEC_CMDLINE obj_type=foo_t
An IMA policy author would have assumed that rule is valid because the
parser accepted it but the result was that measurements for all
KEXEC_CMDLINE operations would be disabled.
Fixes: b0935123a1 ("IMA: Define a new hook to measure the kexec boot command line arguments")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Buffer based hook functions, such as KEXEC_CMDLINE and KEY_CHECK, can
only measure. The process_buffer_measurement() function quietly ignores
all actions except measure so make this behavior clear at the time of
policy load.
The parsing of the keyrings conditional had a check to ensure that it
was only specified with measure actions but the check should be on the
hook function and not the keyrings conditional since
"appraise func=KEY_CHECK" is not a valid rule.
Fixes: b0935123a1 ("IMA: Define a new hook to measure the kexec boot command line arguments")
Fixes: 5808611ccc ("IMA: Add KEY_CHECK func to measure keys")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Use ima_free_rule() to fix memory leaks of allocated ima_rule_entry
members, such as .fsname and .keyrings, when an error is encountered
during rule parsing.
Set the args_p pointer to NULL after freeing it in the error path of
ima_lsm_rule_init() so that it isn't freed twice.
This fixes a memory leak seen when loading an rule that contains an
additional piece of allocated memory, such as an fsname, followed by an
invalid conditional:
# echo "measure fsname=tmpfs bad=cond" > /sys/kernel/security/ima/policy
-bash: echo: write error: Invalid argument
# echo scan > /sys/kernel/debug/kmemleak
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff98e7e4ece6c0 (size 8):
comm "bash", pid 672, jiffies 4294791843 (age 21.855s)
hex dump (first 8 bytes):
74 6d 70 66 73 00 6b a5 tmpfs.k.
backtrace:
[<00000000abab7413>] kstrdup+0x2e/0x60
[<00000000f11ede32>] ima_parse_add_rule+0x7d4/0x1020
[<00000000f883dd7a>] ima_write_policy+0xab/0x1d0
[<00000000b17cf753>] vfs_write+0xde/0x1d0
[<00000000b8ddfdea>] ksys_write+0x68/0xe0
[<00000000b8e21e87>] do_syscall_64+0x56/0xa0
[<0000000089ea7b98>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: f1b08bbcbd ("ima: define a new policy condition based on the filesystem name")
Fixes: 2b60c0eced ("IMA: Read keyrings= option from the IMA policy")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Create a function, ima_free_rule(), to free all memory associated with
an ima_rule_entry. Use the new function to fix memory leaks of allocated
ima_rule_entry members, such as .fsname and .keyrings, when deleting a
list of rules.
Make the existing ima_lsm_free_rule() function specific to the LSM
audit rule array of an ima_rule_entry and require that callers make an
additional call to kfree to free the ima_rule_entry itself.
This fixes a memory leak seen when loading by a valid rule that contains
an additional piece of allocated memory, such as an fsname, followed by
an invalid rule that triggers a policy load failure:
# echo -e "dont_measure fsname=securityfs\nbad syntax" > \
/sys/kernel/security/ima/policy
-bash: echo: write error: Invalid argument
# echo scan > /sys/kernel/debug/kmemleak
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff9bab67ca12c0 (size 16):
comm "bash", pid 684, jiffies 4295212803 (age 252.344s)
hex dump (first 16 bytes):
73 65 63 75 72 69 74 79 66 73 00 6b 6b 6b 6b a5 securityfs.kkkk.
backtrace:
[<00000000adc80b1b>] kstrdup+0x2e/0x60
[<00000000d504cb0d>] ima_parse_add_rule+0x7d4/0x1020
[<00000000444825ac>] ima_write_policy+0xab/0x1d0
[<000000002b7f0d6c>] vfs_write+0xde/0x1d0
[<0000000096feedcf>] ksys_write+0x68/0xe0
[<0000000052b544a2>] do_syscall_64+0x56/0xa0
[<000000007ead1ba7>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: f1b08bbcbd ("ima: define a new policy condition based on the filesystem name")
Fixes: 2b60c0eced ("IMA: Read keyrings= option from the IMA policy")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Ask the LSM to free its audit rule rather than directly calling kfree().
Both AppArmor and SELinux do additional work in their audit_rule_free()
hooks. Fix memory leaks by allowing the LSMs to perform necessary work.
Fixes: b169424551 ("ima: use the lsm policy update notifier")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Janne Karhunen <janne.karhunen@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Error code is not included in the audit messages logged by
the integrity subsystem.
Define a new function integrity_audit_message() that takes error code
in the "errno" parameter. Add "errno" field in the audit messages logged
by the integrity subsystem and set the value passed in the "errno"
parameter.
[ 6.303048] audit: type=1804 audit(1592506281.627:2): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=kernel op=measuring_key cause=ENOMEM comm="swapper/0" name=".builtin_trusted_keys" res=0 errno=-12
[ 7.987647] audit: type=1802 audit(1592506283.312:9): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 op=policy_update cause=completed comm="systemd" res=1 errno=0
[ 8.019432] audit: type=1804 audit(1592506283.344:10): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 op=measuring_kexec_cmdline cause=hashing_error comm="systemd" name="kexec-cmdline" res=0 errno=-22
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Steve Grubb <sgrubb@redhat.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
smk_write_relabel_self() frees memory from the task's credentials with
no locking, which can easily cause a use-after-free because multiple
tasks can share the same credentials structure.
Fix this by using prepare_creds() and commit_creds() to correctly modify
the task's credentials.
Reproducer for "BUG: KASAN: use-after-free in smk_write_relabel_self":
#include <fcntl.h>
#include <pthread.h>
#include <unistd.h>
static void *thrproc(void *arg)
{
int fd = open("/sys/fs/smackfs/relabel-self", O_WRONLY);
for (;;) write(fd, "foo", 3);
}
int main()
{
pthread_t t;
pthread_create(&t, NULL, thrproc, NULL);
thrproc(NULL);
}
Reported-by: syzbot+e6416dabb497a650da40@syzkaller.appspotmail.com
Fixes: 38416e5393 ("Smack: limited capability for changing process label")
Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Move (most of) the definitions of hashtab_search() and hashtab_insert()
to the header file. In combination with the previous patch, this avoids
calling the callbacks indirectly by function pointers and allows for
better optimization, leading to a drastic performance improvement of
these operations.
With this patch, I measured a speed up in the following areas (measured
on x86_64 F32 VM with 4 CPUs):
1. Policy load (`load_policy`) - takes ~150 ms instead of ~230 ms.
2. `chcon -R unconfined_u:object_r:user_tmp_t:s0:c381,c519 /tmp/linux-src`
where /tmp/linux-src is an extracted linux-5.7 source tarball -
takes ~522 ms instead of ~576 ms. This is because of many
symtab_search() calls in string_to_context_struct() when there are
many categories specified in the context.
3. `stress-ng --msg 1 --msg-ops 10000000` - takes 12.41 s instead of
13.95 s (consumes 18.6 s of kernel CPU time instead of 21.6 s).
This is thanks to security_transition_sid() being ~43% faster after
this patch.
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>
Refactor searching and inserting into hashtabs to pave the way for
converting hashtab_search() and hashtab_insert() to inline functions in
the next patch. This will avoid indirect calls and allow the compiler to
better optimize individual callers, leading to a significant performance
improvement.
In order to avoid the indirect calls, the key hashing and comparison
callbacks need to be extracted from the hashtab struct and passed
directly to hashtab_search()/_insert() by the callers so that the
callback address is always known at compile time. The kernel's
rhashtable library (<linux/rhashtable*.h>) does the same thing.
This of course makes the hashtab functions slightly easier to misuse by
passing a wrong callback set, but unfortunately there is no better way
to implement a hash table that is both generic and efficient in C. This
patch tries to somewhat mitigate this by only calling the hashtab
functions in the same file where the corresponding callbacks are
defined (wrapping them into more specialized functions as needed).
Note that this patch doesn't bring any benefit without also moving the
definitions of hashtab_search() and -_insert() to the header file, which
is done in a follow-up patch for easier review of the hashtab.c changes
in this patch.
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>
This encapsulates symtab a little better and will help with further
refactoring later.
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>
The LSM_AUDIT_DATA_* records for PATH, FILE, IOCTL_OP, DENTRY and INODE
are incomplete without the task context of the AUDIT Current Working
Directory record. Add it.
This record addition can't use audit_dummy_context to determine whether
or not to store the record information since the LSM_AUDIT_DATA_*
records are initiated by various LSMs independent of any audit rules.
context->in_syscall is used to determine if it was called in user
context like audit_getname.
Please see the upstream issue
https://github.com/linux-audit/audit-kernel/issues/96
Adapted from Vladis Dronov's v2 patch.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
1) Fix hook iteration and default value for inode_copy_up_xattr
from KP Singh <kpsingh@google.com>
2) Fix the key_permission LSM hook function type
from Sami Tolvanen <samitolvanen@google.com>
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Merge tag 'fixes-v5.8-rc3-a' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem fixes from James Morris:
"Two simple fixes for v5.8:
- Fix hook iteration and default value for inode_copy_up_xattr
(KP Singh)
- Fix the key_permission LSM hook function type (Sami Tolvanen)"
* tag 'fixes-v5.8-rc3-a' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
security: Fix hook iteration and default value for inode_copy_up_xattr
security: fix the key_permission LSM hook function type
`sizeof buf` changed to `sizeof(buf)`
Signed-off-by: Ethan Edwards <ethancarteredwards@gmail.com>
[PM: rewrote the subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Registers 8-9 are used to store measurements of the kernel and its
command line (e.g., grub2 bootloader with tpm module enabled). IMA
should include them in the boot aggregate. Registers 8-9 should be
only included in non-SHA1 digests to avoid ambiguity.
Signed-off-by: Maurizio Drocco <maurizio.drocco@ibm.com>
Reviewed-by: Bruno Meneguele <bmeneg@redhat.com>
Tested-by: Bruno Meneguele <bmeneg@redhat.com> (TPM 1.2, TPM 2.0)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Move most of the block related definition out of fs.h into more suitable
headers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In general SELinux no longer treats undefined object classes or permissions
in the policy as a fatal error, instead handling them in accordance with
handle_unknown. However, the process class and process transition and
dyntransition permissions are still required to be defined due to
dependencies on these definitions for default labeling behaviors,
role and range transitions in older policy versions that lack an explicit
class field, and role allow checking. Log error messages in these cases
since otherwise the policy load will fail silently with no indication
to the user as to the underlying cause. While here, fix the checking for
process transition / dyntransition so that omitting either permission is
handled as an error; both are needed in order to ensure that role allow
checking is consistently applied.
Reported-by: bauen1 <j2468h@googlemail.com>
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This patch does for `getxattr` what commit 3e3e24b420 ("selinux: allow
labeling before policy is loaded") did for `setxattr`; it allows
querying the current SELinux label on disk before the policy is loaded.
One of the motivations described in that commit message also drives this
patch: for Fedora CoreOS (and eventually RHEL CoreOS), we want to be
able to move the root filesystem for example, from xfs to ext4 on RAID,
on first boot, at initrd time.[1]
Because such an operation works at the filesystem level, we need to be
able to read the SELinux labels first from the original root, and apply
them to the files of the new root. The previous commit enabled the
second part of this process; this commit enables the first part.
[1] https://github.com/coreos/fedora-coreos-tracker/issues/94
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Jonathan Lebon <jlebon@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
inode_copy_up_xattr returns 0 to indicate the acceptance of the xattr
and 1 to reject it. If the LSM does not know about the xattr, it's
expected to return -EOPNOTSUPP, which is the correct default value for
this hook. BPF LSM, currently, uses 0 as the default value and thereby
falsely allows all overlay fs xattributes to be copied up.
The iteration logic is also updated from the "bail-on-fail"
call_int_hook to continue on the non-decisive -EOPNOTSUPP and bail out
on other values.
Fixes: 98e828a065 ("security: Refactor declaration of LSM hooks")
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Merge tag 'selinux-pr-20200621' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull SELinux fixes from Paul Moore:
"Three small patches to fix problems in the SELinux code, all found via
clang.
Two patches fix potential double-free conditions and one fixes an
undefined return value"
* tag 'selinux-pr-20200621' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: fix undefined return of cond_evaluate_expr
selinux: fix a double free in cond_read_node()/cond_read_list()
selinux: fix double free
clang static analysis reports an undefined return
security/selinux/ss/conditional.c:79:2: warning: Undefined or garbage value returned to caller [core.uninitialized.UndefReturn]
return s[0];
^~~~~~~~~~~
static int cond_evaluate_expr( ...
{
u32 i;
int s[COND_EXPR_MAXDEPTH];
for (i = 0; i < expr->len; i++)
...
return s[0];
When expr->len is 0, the loop which sets s[0] never runs.
So return -1 if the loop never runs.
Cc: stable@vger.kernel.org
Signed-off-by: Tom Rix <trix@redhat.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Clang static analysis reports this double free error
security/selinux/ss/conditional.c:139:2: warning: Attempt to free released memory [unix.Malloc]
kfree(node->expr.nodes);
^~~~~~~~~~~~~~~~~~~~~~~
When cond_read_node fails, it calls cond_node_destroy which frees the
node but does not poison the entry in the node list. So when it
returns to its caller cond_read_list, cond_read_list deletes the
partial list. The latest entry in the list will be deleted twice.
So instead of freeing the node in cond_read_node, let list freeing in
code_read_list handle the freeing the problem node along with all of the
earlier nodes.
Because cond_read_node no longer does any error handling, the goto's
the error case are redundant. Instead just return the error code.
Cc: stable@vger.kernel.org
Fixes: 60abd3181d ("selinux: convert cond_list to array")
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: subject line tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>
In addition to -ftrivial-auto-var-init=pattern (used by
CONFIG_INIT_STACK_ALL now) Clang also supports zero initialization for
locals enabled by -ftrivial-auto-var-init=zero. The future of this flag
is still being debated (see https://bugs.llvm.org/show_bug.cgi?id=45497).
Right now it is guarded by another flag,
-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang,
which means it may not be supported by future Clang releases. Another
possible resolution is that -ftrivial-auto-var-init=zero will persist
(as certain users have already started depending on it), but the name
of the guard flag will change.
In the meantime, zero initialization has proven itself as a good
production mitigation measure against uninitialized locals. Unlike pattern
initialization, which has a higher chance of triggering existing bugs,
zero initialization provides safe defaults for strings, pointers, indexes,
and sizes. On the other hand, pattern initialization remains safer for
return values. Chrome OS and Android are moving to using zero
initialization for production builds.
Performance-wise, the difference between pattern and zero initialization
is usually negligible, although the generated code for zero
initialization is more compact.
This patch renames CONFIG_INIT_STACK_ALL to CONFIG_INIT_STACK_ALL_PATTERN
and introduces another config option, CONFIG_INIT_STACK_ALL_ZERO, that
enables zero initialization for locals if the corresponding flags are
supported by Clang.
Cc: Kees Cook <keescook@chromium.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alexander Potapenko <glider@google.com>
Link: https://lore.kernel.org/r/20200616083435.223038-1-glider@google.com
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Waiman Long