Age | Commit message (Collapse) | Author |
|
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity subsystem updates from Mimi Zohar:
"The large majority of the changes are EVM portable & immutable
signature related: removing a dependency on loading an HMAC key,
safely allowing file metadata included in the EVM portable & immutable
signatures to be modified, allowing EVM signatures to fulfill IMA file
signature policy requirements, including the EVM file metadata
signature in lieu of an IMA file data signature in the measurement
list, and adding dynamic debugging of EVM file metadata.
In addition, in order to detect critical data or file change
reversions, duplicate measurement records are permitted in the IMA
measurement list.
The remaining patches address compiler, sparse, and doc warnings"
* tag 'integrity-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: (31 commits)
evm: Check xattr size discrepancy between kernel and user
evm: output EVM digest calculation info
IMA: support for duplicate measurement records
ima: Fix warning: no previous prototype for function 'ima_add_kexec_buffer'
ima: differentiate between EVM failures in the audit log
ima: Fix fall-through warning for Clang
ima: Pass NULL instead of 0 to ima_get_action() in ima_file_mprotect()
ima: Include header defining ima_post_key_create_or_update()
ima/evm: Fix type mismatch
ima: Set correct casting types
doc: Fix warning in Documentation/security/IMA-templates.rst
evm: Don't return an error in evm_write_xattrs() if audit is not enabled
ima: Define new template evm-sig
ima: Define new template fields xattrnames, xattrlengths and xattrvalues
evm: Verify portable signatures against all protected xattrs
ima: Define new template field imode
ima: Define new template fields iuid and igid
ima: Add ima_show_template_uint() template library function
ima: Don't remove security.ima if file must not be appraised
ima: Introduce template field evmsig and write to field sig as fallback
...
|
|
The kernel and the user obtain an xattr value in two different ways:
kernel (EVM): uses vfs_getxattr_alloc() which obtains the xattr value from
the filesystem handler (raw value);
user (ima-evm-utils): uses vfs_getxattr() which obtains the xattr value
from the LSMs (normalized value).
Normally, this does not have an impact unless security.selinux is set with
setfattr, with a value not terminated by '\0' (this is not the recommended
way, security.selinux should be set with the appropriate tools such as
chcon and restorecon).
In this case, the kernel and the user see two different xattr values: the
former sees the xattr value without '\0' (raw value), the latter sees the
value with '\0' (value normalized by SELinux).
This could result in two different verification outcomes from EVM and
ima-evm-utils, if a signature was calculated with a security.selinux value
terminated by '\0' and the value set in the filesystem is not terminated by
'\0'. The former would report verification failure due to the missing '\0',
while the latter would report verification success (because it gets the
normalized value with '\0').
This patch mitigates this issue by comparing in evm_calc_hmac_or_hash() the
size of the xattr returned by the two xattr functions and by warning the
user if there is a discrepancy.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Output the data used in calculating the EVM digest and the resulting
digest as ascii hexadecimal strings.
Suggested-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> (CONFIG_DYNAMIC_DEBUG)
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reported-by: kernel test robot <lkp@intel.com> (Use %zu for size_t)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Fix gcc W=1 warnings:
security/tomoyo/audit.c:331: warning: Function parameter or member 'matched_acl' not described in 'tomoyo_get_audit'
security/tomoyo/securityfs_if.c:146: warning: Function parameter or member 'inode' not described in 'tomoyo_release'
security/tomoyo/tomoyo.c:122: warning: Function parameter or member 'path' not described in 'tomoyo_inode_getattr'
security/tomoyo/tomoyo.c:497: warning: Function parameter or member 'clone_flags' not described in 'tomoyo_task_alloc'
security/tomoyo/util.c:92: warning: Function parameter or member 'time64' not described in 'tomoyo_convert_time'
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
[ penguin-kernel: Also adjust spaces and similar warnings ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
|
|
IMA measures contents of a given file/buffer/critical-data record,
and properly re-measures it on change. However, IMA does not measure
the duplicate value for a given record, since TPM extend is a very
expensive operation. For example, if the record changes from value
'v#1' to 'v#2', and then back to 'v#1', IMA will not measure and log
the last change to 'v#1', since the hash of 'v#1' for that record is
already present in the IMA htable. This limits the ability of an
external attestation service to accurately determine the current state
of the system. The service would incorrectly conclude that the latest
value of the given record on the system is 'v#2', and act accordingly.
Define and use a new Kconfig option IMA_DISABLE_HTABLE to permit
duplicate records in the IMA measurement list.
In addition to the duplicate measurement records described above,
other duplicate file measurement records may be included in the log,
when CONFIG_IMA_DISABLE_HTABLE is enabled. For example,
- i_version is not enabled,
- i_generation changed,
- same file present on different filesystems,
- an inode is evicted from dcache
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
[zohar@linux.ibm.com: updated list of duplicate measurement records]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
The function prototype for ima_add_kexec_buffer() is present
in 'linux/ima.h'. But this header file is not included in
ima_kexec.c where the function is implemented. This results
in the following compiler warning when "-Wmissing-prototypes" flag
is turned on:
security/integrity/ima/ima_kexec.c:81:6: warning: no previous prototype
for function 'ima_add_kexec_buffer' [-Wmissing-prototypes]
Include the header file 'linux/ima.h' in ima_kexec.c to fix
the compiler warning.
Fixes: dce92f6b11c3 (arm64: Enable passing IMA log to next kernel on kexec)
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Differentiate between an invalid EVM portable signature failure
from other EVM HMAC/signature failures.
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
In preparation to enable -Wimplicit-fallthrough for Clang, fix a
fall-through warning by explicitly adding a break statement instead
of just letting the code fall through to the next case.
Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch fixes the sparse warning:
sparse: warning: Using plain integer as NULL pointer
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch fixes the sparse warning for ima_post_key_create_or_update() by
adding the header file that defines the prototype (linux/ima.h).
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
The endianness of a variable written to the measurement list cannot be
determined at compile time, as it depends on the value of the
ima_canonical_fmt global variable (set through a kernel option with the
same name if the machine is big endian).
If ima_canonical_fmt is false, the endianness of a variable is the same as
the machine; if ima_canonical_fmt is true, the endianness is little endian.
The warning arises due to this type of instruction:
var = cpu_to_leXX(var)
which tries to assign a value in little endian to a variable with native
endianness (little or big endian).
Given that the variables set with this instruction are not used in any
operation but just written to a buffer, it is safe to force the type of the
value being set to be the same of the type of the variable with:
var = (__force <var type>)cpu_to_leXX(var)
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
The code expects that the values being parsed from a buffer when the
ima_canonical_fmt global variable is true are in little endian. Thus, this
patch sets the casting types accordingly.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch avoids that evm_write_xattrs() returns an error when audit is
not enabled. The ab variable can be NULL and still be passed to the other
audit_log_() functions, as those functions do not include any instruction.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
With the recent introduction of the evmsig template field, remote verifiers
can obtain the EVM portable signature instead of the IMA signature, to
verify file metadata.
After introducing the new fields to include file metadata in the
measurement list, this patch finally defines the evm-sig template, whose
format is:
d-ng|n-ng|evmsig|xattrnames|xattrlengths|xattrvalues|iuid|igid|imode
xattrnames, xattrlengths and xattrvalues are populated only from defined
EVM protected xattrs, i.e. the ones that EVM considers to verify the
portable signature. xattrnames and xattrlengths are populated only if the
xattr is present.
xattrnames and xattrlengths are not necessary for verifying the EVM
portable signature, but they are included for completeness of information,
if a remote verifier wants to infer more from file metadata.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch defines the new template fields xattrnames, xattrlengths and
xattrvalues, which contain respectively a list of xattr names (strings,
separated by |), lengths (u32, hex) and values (hex). If an xattr is not
present, the name and length are not displayed in the measurement list.
Reported-by: kernel test robot <lkp@intel.com> (Missing prototype def)
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Currently, the evm_config_default_xattrnames array contains xattr names
only related to LSMs which are enabled in the kernel configuration.
However, EVM portable signatures do not depend on local information and a
vendor might include in the signature calculation xattrs that are not
enabled in the target platform.
Just including all xattrs names in evm_config_default_xattrnames is not a
safe approach, because a target system might have already calculated
signatures or HMACs based only on the enabled xattrs. After applying this
patch, EVM would verify those signatures and HMACs with all xattrs instead.
The non-enabled ones, which could possibly exist, would cause a
verification error.
Thus, this patch adds a new field named enabled to the xattr_list
structure, which is set to true if the LSM associated to a given xattr name
is enabled in the kernel configuration. The non-enabled xattrs are taken
into account only in evm_calc_hmac_or_hash(), if the passed security.evm
type is EVM_XATTR_PORTABLE_DIGSIG.
The new function evm_protected_xattr_if_enabled() has been defined so that
IMA can include all protected xattrs and not only the enabled ones in the
measurement list, if the new template fields xattrnames, xattrlengths or
xattrvalues have been included in the template format.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch defines the new template field imode, which includes the
inode mode. It can be used by a remote verifier to verify the EVM portable
signature, if it was included with the template fields sig or evmsig.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch defines the new template fields iuid and igid, which include
respectively the inode UID and GID. For idmapped mounts, still the original
UID and GID are provided.
These fields can be used to verify the EVM portable signature, if it was
included with the template fields sig or evmsig.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
This patch introduces the new function ima_show_template_uint(). This can
be used for showing integers of different sizes in ASCII format. The
function ima_show_template_data_ascii() automatically determines how to
print a stored integer by checking the integer size.
If integers have been written in canonical format,
ima_show_template_data_ascii() calls the appropriate leXX_to_cpu() function
to correctly display the value.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
Files might come from a remote source and might have xattrs, including
security.ima. It should not be IMA task to decide whether security.ima
should be kept or not. This patch removes the removexattr() system
call in ima_inode_post_setattr().
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
With the patch to accept EVM portable signatures when the
appraise_type=imasig requirement is specified in the policy, appraisal can
be successfully done even if the file does not have an IMA signature.
However, remote attestation would not see that a different signature type
was used, as only IMA signatures can be included in the measurement list.
This patch solves the issue by introducing the new template field 'evmsig'
to show EVM portable signatures and by including its value in the existing
field 'sig' if the IMA signature is not found.
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
System administrators can require that all accessed files have a signature
by specifying appraise_type=imasig in a policy rule.
Currently, IMA signatures satisfy this requirement. Appended signatures may
also satisfy this requirement, but are not applicable as IMA signatures.
IMA/appended signatures ensure data source authentication for file content
and prevent any change. EVM signatures instead ensure data source
authentication for file metadata. Given that the digest or signature of the
file content must be included in the metadata, EVM signatures provide the
same file data guarantees of IMA signatures, as well as providing file
metadata guarantees.
This patch lets systems protected with EVM signatures pass appraisal
verification if the appraise_type=imasig requirement is specified in the
policy. This facilitates deployment in the scenarios where only EVM
signatures are available.
The patch makes the following changes:
file xattr types:
security.ima: IMA_XATTR_DIGEST/IMA_XATTR_DIGEST_NG
security.evm: EVM_XATTR_PORTABLE_DIGSIG
execve(), mmap(), open() behavior (with appraise_type=imasig):
before: denied (file without IMA signature, imasig requirement not met)
after: allowed (file with EVM portable signature, imasig requirement met)
open(O_WRONLY) behavior (without appraise_type=imasig):
before: allowed (file without IMA signature, not immutable)
after: denied (file with EVM portable signature, immutable)
In addition, similarly to IMA signatures, this patch temporarily allows
new files without or with incomplete metadata to be opened so that content
can be written.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
With the patch to allow xattr/attr operations if a portable signature
verification fails, cp and tar can copy all xattrs/attrs so that at the
end of the process verification succeeds.
However, it might happen that the xattrs/attrs are already set to the
correct value (taken at signing time) and signature verification succeeds
before the copy has completed. For example, an archive might contains files
owned by root and the archive is extracted by root.
Then, since portable signatures are immutable, all subsequent operations
fail (e.g. fchown()), even if the operation is legitimate (does not alter
the current value).
This patch avoids this problem by reporting successful operation to user
space when that operation does not alter the current value of xattrs/attrs.
With this patch, the one that introduces evm_hmac_disabled() and the one
that allows a metadata operation on the INTEGRITY_FAIL_IMMUTABLE error, EVM
portable signatures can be used without disabling metadata verification
(by setting EVM_ALLOW_METADATA_WRITES). Due to keeping metadata
verification enabled, altering immutable metadata protected with a portable
signature that was successfully verified will be denied (existing
behavior).
Reported-by: kernel test robot <lkp@intel.com> [implicit declaration of function]
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
In preparation for 'evm: Allow setxattr() and setattr() for unmodified
metadata', this patch passes mnt_userns to the inode set/remove xattr hooks
so that the GID of the inode on an idmapped mount is correctly determined
by posix_acl_update_mode().
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
If files with portable signatures are copied from one location to another
or are extracted from an archive, verification can temporarily fail until
all xattrs/attrs are set in the destination. Only portable signatures may
be moved or copied from one file to another, as they don't depend on
system-specific information such as the inode generation. Instead portable
signatures must include security.ima.
Unlike other security.evm types, EVM portable signatures are also
immutable. Thus, it wouldn't be a problem to allow xattr/attr operations
when verification fails, as portable signatures will never be replaced with
the HMAC on possibly corrupted xattrs/attrs.
This patch first introduces a new integrity status called
INTEGRITY_FAIL_IMMUTABLE, that allows callers of
evm_verify_current_integrity() to detect that a portable signature didn't
pass verification and then adds an exception in evm_protect_xattr() and
evm_inode_setattr() for this status and returns 0 instead of -EPERM.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
When a file is being created, LSMs can set the initial label with the
inode_init_security hook. If no HMAC key is loaded, the new file will have
LSM xattrs but not the HMAC. It is also possible that the file remains
without protected xattrs after creation if no active LSM provided it, or
because the filesystem does not support them.
Unfortunately, EVM will deny any further metadata operation on new files,
as evm_protect_xattr() will return the INTEGRITY_NOLABEL error if protected
xattrs exist without security.evm, INTEGRITY_NOXATTRS if no protected
xattrs exist or INTEGRITY_UNKNOWN if xattrs are not supported. This would
limit the usability of EVM when only a public key is loaded, as commands
such as cp or tar with the option to preserve xattrs won't work.
This patch introduces the evm_hmac_disabled() function to determine whether
or not it is safe to ignore verification errors, based on the ability of
EVM to calculate HMACs. If the HMAC key is not loaded, and it cannot be
loaded in the future due to the EVM_SETUP_COMPLETE initialization flag,
allowing an operation despite the attrs/xattrs being found invalid will not
make them valid.
Since the post hooks can be executed even when the HMAC key is not loaded,
this patch also ensures that the EVM_INIT_HMAC initialization flag is set
before the post hooks call evm_update_evmxattr().
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Suggested-by: Mimi Zohar <zohar@linux.ibm.com> (for ensuring EVM_INIT_HMAC is set)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
When EVM_ALLOW_METADATA_WRITES is set, EVM allows any operation on
metadata. Its main purpose is to allow users to freely set metadata when it
is protected by a portable signature, until an HMAC key is loaded.
However, callers of evm_verifyxattr() are not notified about metadata
changes and continue to rely on the last status returned by the function.
For example IMA, since it caches the appraisal result, will not call again
evm_verifyxattr() until the appraisal flags are cleared, and will grant
access to the file even if there was a metadata operation that made the
portable signature invalid.
This patch introduces evm_revalidate_status(), which callers of
evm_verifyxattr() can use in their xattr hooks to determine whether
re-validation is necessary and to do the proper actions. IMA calls it in
its xattr hooks to reset the appraisal flags, so that the EVM status is
re-evaluated after a metadata operation.
Lastly, this patch also adds a call to evm_reset_status() in
evm_inode_post_setattr() to invalidate the cached EVM status after a
setattr operation.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
EVM_ALLOW_METADATA_WRITES is an EVM initialization flag that can be set to
temporarily disable metadata verification until all xattrs/attrs necessary
to verify an EVM portable signature are copied to the file. This flag is
cleared when EVM is initialized with an HMAC key, to avoid that the HMAC is
calculated on unverified xattrs/attrs.
Currently EVM unnecessarily denies setting this flag if EVM is initialized
with a public key, which is not a concern as it cannot be used to trust
xattrs/attrs updates. This patch removes this limitation.
Fixes: ae1ba1676b88e ("EVM: Allow userland to permit modification of EVM-protected metadata")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org # 4.16.x
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
The public builtin keys do not need to be appraised by IMA as the
restriction on the IMA/EVM trusted keyrings ensures that a key can be
loaded only if it is signed with a key on the builtin or secondary
keyrings.
However, when evm_load_x509() is called, appraisal is already enabled and
a valid IMA signature must be added to the EVM key to pass verification.
Since the restriction is applied on both IMA and EVM trusted keyrings, it
is safe to disable appraisal also when the EVM key is loaded. This patch
calls evm_load_x509() inside ima_load_x509() if CONFIG_IMA_LOAD_X509 is
enabled, which crosses the normal IMA and EVM boundary.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
evm_inode_init_security() requires an HMAC key to calculate the HMAC on
initial xattrs provided by LSMs. However, it checks generically whether a
key has been loaded, including also public keys, which is not correct as
public keys are not suitable to calculate the HMAC.
Originally, support for signature verification was introduced to verify a
possibly immutable initial ram disk, when no new files are created, and to
switch to HMAC for the root filesystem. By that time, an HMAC key should
have been loaded and usable to calculate HMACs for new files.
More recently support for requiring an HMAC key was removed from the
kernel, so that signature verification can be used alone. Since this is a
legitimate use case, evm_inode_init_security() should not return an error
when no HMAC key has been loaded.
This patch fixes this problem by replacing the evm_key_loaded() check with
a check of the EVM_INIT_HMAC flag in evm_initialized.
Fixes: 26ddabfe96b ("evm: enable EVM when X509 certificate is loaded")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org # 4.5.x
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
EVM_SETUP_COMPLETE is defined as 0x80000000, which is larger than INT_MAX.
The "-fno-strict-overflow" compiler option properly prevents signaling
EVM that the EVM policy setup is complete. Define and read an unsigned
int.
Fixes: f00d79750712 ("EVM: Allow userspace to signal an RSA key has been loaded")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
|
|
The `tpm_get_ops` call at the beginning of the function is not paired
with a `tpm_put_ops` on this return path.
Cc: stable@vger.kernel.org
Fixes: f2219745250f ("security: keys: trusted: use ASN.1 TPM2 key format for the blobs")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ben Boeckel <mathstuf@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
|
|
Two error return paths are neglecting to free allocated object td,
causing a memory leak. Fix this by returning via the error return
path that securely kfree's td.
Fixes clang scan-build warning:
security/keys/trusted-keys/trusted_tpm1.c:496:10: warning: Potential
memory leak [unix.Malloc]
Cc: stable@vger.kernel.org
Fixes: 5df16caada3f ("KEYS: trusted: Fix incorrect handling of tpm_get_random()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
|
|
Pull SafeSetID update from Micah Morton:
"Simple code cleanup
This just has a single three-line code cleanup to eliminate some
unnecessary 'break' statements"
* tag 'safesetid-5.13' of git://github.com/micah-morton/linux:
LSM: SafeSetID: Fix code specification by scripts/checkpatch.pl
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
"Assorted stuff all over the place"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
useful constants: struct qstr for ".."
hostfs_open(): don't open-code file_dentry()
whack-a-mole: kill strlen_user() (again)
autofs: should_expire() argument is guaranteed to be positive
apparmor:match_mn() - constify devpath argument
buffer: a small optimization in grow_buffers
get rid of autofs_getpath()
constify dentry argument of dentry_path()/dentry_path_raw()
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull Landlock LSM from James Morris:
"Add Landlock, a new LSM from Mickaël Salaün.
Briefly, Landlock provides for unprivileged application sandboxing.
From Mickaël's cover letter:
"The goal of Landlock is to enable to restrict ambient rights (e.g.
global filesystem access) for a set of processes. Because Landlock
is a stackable LSM [1], it makes possible to create safe security
sandboxes as new security layers in addition to the existing
system-wide access-controls. This kind of sandbox is expected to
help mitigate the security impact of bugs or unexpected/malicious
behaviors in user-space applications. Landlock empowers any
process, including unprivileged ones, to securely restrict
themselves.
Landlock is inspired by seccomp-bpf but instead of filtering
syscalls and their raw arguments, a Landlock rule can restrict the
use of kernel objects like file hierarchies, according to the
kernel semantic. Landlock also takes inspiration from other OS
sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD
Pledge/Unveil.
In this current form, Landlock misses some access-control features.
This enables to minimize this patch series and ease review. This
series still addresses multiple use cases, especially with the
combined use of seccomp-bpf: applications with built-in sandboxing,
init systems, security sandbox tools and security-oriented APIs [2]"
The cover letter and v34 posting is here:
https://lore.kernel.org/linux-security-module/20210422154123.13086-1-mic@digikod.net/
See also:
https://landlock.io/
This code has had extensive design discussion and review over several
years"
Link: https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@schaufler-ca.com/ [1]
Link: https://lore.kernel.org/lkml/f646e1c7-33cf-333f-070c-0a40ad0468cd@digikod.net/ [2]
* tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
landlock: Enable user space to infer supported features
landlock: Add user and kernel documentation
samples/landlock: Add a sandbox manager example
selftests/landlock: Add user space tests
landlock: Add syscall implementations
arch: Wire up Landlock syscalls
fs,security: Add sb_delete hook
landlock: Support filesystem access-control
LSM: Infrastructure management of the superblock
landlock: Add ptrace restrictions
landlock: Set up the security framework and manage credentials
landlock: Add ruleset and domain management
landlock: Add object management
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull IMA updates from Mimi Zohar:
"In addition to loading the kernel module signing key onto the builtin
keyring, load it onto the IMA keyring as well.
Also six trivial changes and bug fixes"
* tag 'integrity-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: ensure IMA_APPRAISE_MODSIG has necessary dependencies
ima: Fix fall-through warnings for Clang
integrity: Add declarations to init_once void arguments.
ima: Fix function name error in comment.
ima: enable loading of build time generated key on .ima keyring
ima: enable signing of modules with build time generated key
keys: cleanup build time module signing keys
ima: Fix the error code for restoring the PCR value
ima: without an IMA policy loaded, return quickly
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core:
- bpf:
- allow bpf programs calling kernel functions (initially to
reuse TCP congestion control implementations)
- enable task local storage for tracing programs - remove the
need to store per-task state in hash maps, and allow tracing
programs access to task local storage previously added for
BPF_LSM
- add bpf_for_each_map_elem() helper, allowing programs to walk
all map elements in a more robust and easier to verify fashion
- sockmap: support UDP and cross-protocol BPF_SK_SKB_VERDICT
redirection
- lpm: add support for batched ops in LPM trie
- add BTF_KIND_FLOAT support - mostly to allow use of BTF on
s390 which has floats in its headers files
- improve BPF syscall documentation and extend the use of kdoc
parsing scripts we already employ for bpf-helpers
- libbpf, bpftool: support static linking of BPF ELF files
- improve support for encapsulation of L2 packets
- xdp: restructure redirect actions to avoid a runtime lookup,
improving performance by 4-8% in microbenchmarks
- xsk: build skb by page (aka generic zerocopy xmit) - improve
performance of software AF_XDP path by 33% for devices which don't
need headers in the linear skb part (e.g. virtio)
- nexthop: resilient next-hop groups - improve path stability on
next-hops group changes (incl. offload for mlxsw)
- ipv6: segment routing: add support for IPv4 decapsulation
- icmp: add support for RFC 8335 extended PROBE messages
- inet: use bigger hash table for IP ID generation
- tcp: deal better with delayed TX completions - make sure we don't
give up on fast TCP retransmissions only because driver is slow in
reporting that it completed transmitting the original
- tcp: reorder tcp_congestion_ops for better cache locality
- mptcp:
- add sockopt support for common TCP options
- add support for common TCP msg flags
- include multiple address ids in RM_ADDR
- add reset option support for resetting one subflow
- udp: GRO L4 improvements - improve 'forward' / 'frag_list'
co-existence with UDP tunnel GRO, allowing the first to take place
correctly even for encapsulated UDP traffic
- micro-optimize dev_gro_receive() and flow dissection, avoid
retpoline overhead on VLAN and TEB GRO
- use less memory for sysctls, add a new sysctl type, to allow using
u8 instead of "int" and "long" and shrink networking sysctls
- veth: allow GRO without XDP - this allows aggregating UDP packets
before handing them off to routing, bridge, OvS, etc.
- allow specifing ifindex when device is moved to another namespace
- netfilter:
- nft_socket: add support for cgroupsv2
- nftables: add catch-all set element - special element used to
define a default action in case normal lookup missed
- use net_generic infra in many modules to avoid allocating
per-ns memory unnecessarily
- xps: improve the xps handling to avoid potential out-of-bound
accesses and use-after-free when XPS change race with other
re-configuration under traffic
- add a config knob to turn off per-cpu netdev refcnt to catch
underflows in testing
Device APIs:
- add WWAN subsystem to organize the WWAN interfaces better and
hopefully start driving towards more unified and vendor-
independent APIs
- ethtool:
- add interface for reading IEEE MIB stats (incl. mlx5 and bnxt
support)
- allow network drivers to dump arbitrary SFP EEPROM data,
current offset+length API was a poor fit for modern SFP which
define EEPROM in terms of pages (incl. mlx5 support)
- act_police, flow_offload: add support for packet-per-second
policing (incl. offload for nfp)
- psample: add additional metadata attributes like transit delay for
packets sampled from switch HW (and corresponding egress and
policy-based sampling in the mlxsw driver)
- dsa: improve support for sandwiched LAGs with bridge and DSA
- netfilter:
- flowtable: use direct xmit in topologies with IP forwarding,
bridging, vlans etc.
- nftables: counter hardware offload support
- Bluetooth:
- improvements for firmware download w/ Intel devices
- add support for reading AOSP vendor capabilities
- add support for virtio transport driver
- mac80211:
- allow concurrent monitor iface and ethernet rx decap
- set priority and queue mapping for injected frames
- phy: add support for Clause-45 PHY Loopback
- pci/iov: add sysfs MSI-X vector assignment interface to distribute
MSI-X resources to VFs (incl. mlx5 support)
New hardware/drivers:
- dsa: mv88e6xxx: add support for Marvell mv88e6393x - 11-port
Ethernet switch with 8x 1-Gigabit Ethernet and 3x 10-Gigabit
interfaces.
- dsa: support for legacy Broadcom tags used on BCM5325, BCM5365 and
BCM63xx switches
- Microchip KSZ8863 and KSZ8873; 3x 10/100Mbps Ethernet switches
- ath11k: support for QCN9074 a 802.11ax device
- Bluetooth: Broadcom BCM4330 and BMC4334
- phy: Marvell 88X2222 transceiver support
- mdio: add BCM6368 MDIO mux bus controller
- r8152: support RTL8153 and RTL8156 (USB Ethernet) chips
- mana: driver for Microsoft Azure Network Adapter (MANA)
- Actions Semi Owl Ethernet MAC
- can: driver for ETAS ES58X CAN/USB interfaces
Pure driver changes:
- add XDP support to: enetc, igc, stmmac
- add AF_XDP support to: stmmac
- virtio:
- page_to_skb() use build_skb when there's sufficient tailroom
(21% improvement for 1000B UDP frames)
- support XDP even without dedicated Tx queues - share the Tx
queues with the stack when necessary
- mlx5:
- flow rules: add support for mirroring with conntrack, matching
on ICMP, GTP, flex filters and more
- support packet sampling with flow offloads
- persist uplink representor netdev across eswitch mode changes
- allow coexistence of CQE compression and HW time-stamping
- add ethtool extended link error state reporting
- ice, iavf: support flow filters, UDP Segmentation Offload
- dpaa2-switch:
- move the driver out of staging
- add spanning tree (STP) support
- add rx copybreak support
- add tc flower hardware offload on ingress traffic
- ionic:
- implement Rx page reuse
- support HW PTP time-stamping
- octeon: support TC hardware offloads - flower matching on ingress
and egress ratelimitting.
- stmmac:
- add RX frame steering based on VLAN priority in tc flower
- support frame preemption (FPE)
- intel: add cross time-stamping freq difference adjustment
- ocelot:
- support forwarding of MRP frames in HW
- support multiple bridges
- support PTP Sync one-step timestamping
- dsa: mv88e6xxx, dpaa2-switch: offload bridge port flags like
learning, flooding etc.
- ipa: add IPA v4.5, v4.9 and v4.11 support (Qualcomm SDX55, SM8350,
SC7280 SoCs)
- mt7601u: enable TDLS support
- mt76:
- add support for 802.3 rx frames (mt7915/mt7615)
- mt7915 flash pre-calibration support
- mt7921/mt7663 runtime power management fixes"
* tag 'net-next-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2451 commits)
net: selftest: fix build issue if INET is disabled
net: netrom: nr_in: Remove redundant assignment to ns
net: tun: Remove redundant assignment to ret
net: phy: marvell: add downshift support for M88E1240
net: dsa: ksz: Make reg_mib_cnt a u8 as it never exceeds 255
net/sched: act_ct: Remove redundant ct get and check
icmp: standardize naming of RFC 8335 PROBE constants
bpf, selftests: Update array map tests for per-cpu batched ops
bpf: Add batched ops support for percpu array
bpf: Implement formatted output helpers with bstr_printf
seq_file: Add a seq_bprintf function
sfc: adjust efx->xdp_tx_queue_count with the real number of initialized queues
net:nfc:digital: Fix a double free in digital_tg_recv_dep_req
net: fix a concurrency bug in l2tp_tunnel_register()
net/smc: Remove redundant assignment to rc
mpls: Remove redundant assignment to err
llc2: Remove redundant assignment to rc
net/tls: Remove redundant initialization of record
rds: Remove redundant assignment to nr_sig
dt-bindings: net: mdio-gpio: add compatible for microchip,mdio-smi0
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring:
- Refactor powerpc and arm64 kexec DT handling to common code. This
enables IMA on arm64.
- Add kbuild support for applying DT overlays at build time. The first
user are the DT unittests.
- Fix kerneldoc formatting and W=1 warnings in drivers/of/
- Fix handling 64-bit flag on PCI resources
- Bump dtschema version required to v2021.2.1
- Enable undocumented compatible checks for dtbs_check. This allows
tracking of missing binding schemas.
- DT docs improvements. Regroup the DT docs and add the example schema
and DT kernel ABI docs to the doc build.
- Convert Broadcom Bluetooth and video-mux bindings to schema
- Add QCom sm8250 Venus video codec binding schema
- Add vendor prefixes for AESOP, YIC System Co., Ltd, and Siliconfile
Technologies Inc.
- Cleanup of DT schema type references on common properties and
standard unit properties
* tag 'devicetree-for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (64 commits)
powerpc: If kexec_build_elf_info() fails return immediately from elf64_load()
powerpc: Free fdt on error in elf64_load()
of: overlay: Fix kerneldoc warning in of_overlay_remove()
of: linux/of.h: fix kernel-doc warnings
of/pci: Add IORESOURCE_MEM_64 to resource flags for 64-bit memory addresses
dt-bindings: bcm4329-fmac: add optional brcm,ccode-map
docs: dt: update writing-schema.rst references
dt-bindings: media: venus: Add sm8250 dt schema
of: base: Fix spelling issue with function param 'prop'
docs: dt: Add DT API documentation
of: Add missing 'Return' section in kerneldoc comments
of: Fix kerneldoc output formatting
docs: dt: Group DT docs into relevant sub-sections
docs: dt: Make 'Devicetree' wording more consistent
docs: dt: writing-schema: Include the example schema in the doc build
docs: dt: writing-schema: Remove spurious indentation
dt-bindings: Fix reference in submitting-patches.rst to the DT ABI doc
dt-bindings: ddr: Add optional manufacturer and revision ID to LPDDR3
dt-bindings: media: video-interfaces: Drop the example
devicetree: bindings: clock: Minor typo fix in the file armada3700-tbg-clock.txt
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer fixes from James Morris:
"Miscellaneous minor fixes"
* tag 'fixes-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
security: commoncap: clean up kernel-doc comments
security: commoncap: fix -Wstringop-overread warning
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux updates from Paul Moore:
- Add support for measuring the SELinux state and policy capabilities
using IMA.
- A handful of SELinux/NFS patches to compare the SELinux state of one
mount with a set of mount options. Olga goes into more detail in the
patch descriptions, but this is important as it allows more
flexibility when using NFS and SELinux context mounts.
- Properly differentiate between the subjective and objective LSM
credentials; including support for the SELinux and Smack. My clumsy
attempt at a proper fix for AppArmor didn't quite pass muster so John
is working on a proper AppArmor patch, in the meantime this set of
patches shouldn't change the behavior of AppArmor in any way. This
change explains the bulk of the diffstat beyond security/.
- Fix a problem where we were not properly terminating the permission
list for two SELinux object classes.
* tag 'selinux-pr-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: add proper NULL termination to the secclass_map permissions
smack: differentiate between subjective and objective task credentials
selinux: clarify task subjective and objective credentials
lsm: separate security_task_getsecid() into subjective and objective variants
nfs: account for selinux security context when deciding to share superblock
nfs: remove unneeded null check in nfs_fill_super()
lsm,selinux: add new hook to compare new mount to an existing mount
selinux: fix misspellings using codespell tool
selinux: fix misspellings using codespell tool
selinux: measure state and policy capabilities
selinux: Allow context mounts for unpriviliged overlayfs
|
|
First, the code is found to be irregular through checkpatch.pl.
Then I found break is really useless here.
Signed-off-by: Yanwei Gao <gaoyanwei.tx@gmail.com>
Signed-off-by: Micah Morton <mortonm@chromium.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
"API:
- crypto_destroy_tfm now ignores errors as well as NULL pointers
Algorithms:
- Add explicit curve IDs in ECDH algorithm names
- Add NIST P384 curve parameters
- Add ECDSA
Drivers:
- Add support for Green Sardine in ccp
- Add ecdh/curve25519 to hisilicon/hpre
- Add support for AM64 in sa2ul"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (184 commits)
fsverity: relax build time dependency on CRYPTO_SHA256
fscrypt: relax Kconfig dependencies for crypto API algorithms
crypto: camellia - drop duplicate "depends on CRYPTO"
crypto: s5p-sss - consistently use local 'dev' variable in probe()
crypto: s5p-sss - remove unneeded local variable initialization
crypto: s5p-sss - simplify getting of_device_id match data
ccp: ccp - add support for Green Sardine
crypto: ccp - Make ccp_dev_suspend and ccp_dev_resume void functions
crypto: octeontx2 - add support for OcteonTX2 98xx CPT block.
crypto: chelsio/chcr - Remove useless MODULE_VERSION
crypto: ux500/cryp - Remove duplicate argument
crypto: chelsio - remove unused function
crypto: sa2ul - Add support for AM64
crypto: sa2ul - Support for per channel coherency
dt-bindings: crypto: ti,sa2ul: Add new compatible for AM64
crypto: hisilicon - enable new error types for QM
crypto: hisilicon - add new error type for SEC
crypto: hisilicon - support new error types for ZIP
crypto: hisilicon - dynamic configuration 'err_info'
crypto: doc - fix kernel-doc notation in chacha.c and af_alg.c
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull x509 dbx/mokx UEFI support from David Howells:
"Here's a set of patches from Eric Snowberg[1] that add support for
EFI_CERT_X509_GUID entries in the dbx and mokx UEFI tables (such
entries cause matching certificates to be rejected).
These are currently ignored and only the hash entries are made use of.
Additionally Eric included his patches to allow such certificates to
be preloaded.
These patches deal with CVE-2020-26541.
To quote Eric:
'This is the fifth patch series for adding support for
EFI_CERT_X509_GUID entries [2]. It has been expanded to not only
include dbx entries but also entries in the mokx. Additionally
my series to preload these certificate [3] has also been
included'"
Link: https://lore.kernel.org/r/20210122181054.32635-1-eric.snowberg@oracle.com [1]
Link: https://patchwork.kernel.org/project/linux-security-module/patch/20200916004927.64276-1-eric.snowberg@oracle.com/ [2]
Link: https://lore.kernel.org/patchwork/cover/1315485/ [3]
* tag 'keys-cve-2020-26541-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
integrity: Load mokx variables into the blacklist keyring
certs: Add ability to preload revocation certs
certs: Move load_system_certificate_list to a common function
certs: Add EFI_CERT_X509_GUID support for dbx entries
|
|
Pull tpm fixes from James Bottomley:
"Fix a regression in the TPM trusted keys caused by the generic rework
to add ARM TEE based trusted keys.
Without this fix, the TPM trusted key subsystem fails to add or load
any keys"
* tag 'queue' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/tpmdd:
KEYS: trusted: fix TPM trusted keys for generic framework
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd
Pull tpm updates from Jarkko Sakkinen:
"New features:
- ARM TEE backend for kernel trusted keys to complete the existing
TPM backend
- ASN.1 format for TPM2 trusted keys to make them interact with the
user space stack, such as OpenConnect VPN
Other than that, a bunch of bug fixes"
* tag 'tpmdd-next-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
KEYS: trusted: Fix missing null return from kzalloc call
char: tpm: fix error return code in tpm_cr50_i2c_tis_recv()
MAINTAINERS: Add entry for TEE based Trusted Keys
doc: trusted-encrypted: updates with TEE as a new trust source
KEYS: trusted: Introduce TEE based Trusted Keys
KEYS: trusted: Add generic trusted keys framework
security: keys: trusted: Make sealed key properly interoperable
security: keys: trusted: use ASN.1 TPM2 key format for the blobs
security: keys: trusted: fix TPM2 authorizations
oid_registry: Add TCG defined OIDS for TPM keys
lib: Add ASN.1 encoder
tpm: vtpm_proxy: Avoid reading host log when using a virtual device
tpm: acpi: Check eventlog signature before using it
tpm: efi: Use local variable for calculating final log size
|
|
Add a new flag LANDLOCK_CREATE_RULESET_VERSION to
landlock_create_ruleset(2). This enables to retreive a Landlock ABI
version that is useful to efficiently follow a best-effort security
approach. Indeed, it would be a missed opportunity to abort the whole
sandbox building, because some features are unavailable, instead of
protecting users as much as possible with the subset of features
provided by the running kernel.
This new flag enables user space to identify the minimum set of Landlock
features supported by the running kernel without relying on a filesystem
interface (e.g. /proc/version, which might be inaccessible) nor testing
multiple syscall argument combinations (i.e. syscall bisection). New
Landlock features will be documented and tied to a minimum version
number (greater than 1). The current version will be incremented for
each new kernel release supporting new Landlock features. User space
libraries can leverage this information to seamlessly restrict processes
as much as possible while being compatible with newer APIs.
This is a much more lighter approach than the previous
landlock_get_features(2): the complexity is pushed to user space
libraries. This flag meets similar needs as securityfs versions:
selinux/policyvers, apparmor/features/*/version* and tomoyo/version.
Supporting this flag now will be convenient for backward compatibility.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: James Morris <jmorris@namei.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210422154123.13086-14-mic@digikod.net
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
|
|
These 3 system calls are designed to be used by unprivileged processes
to sandbox themselves:
* landlock_create_ruleset(2): Creates a ruleset and returns its file
descriptor.
* landlock_add_rule(2): Adds a rule (e.g. file hierarchy access) to a
ruleset, identified by the dedicated file descriptor.
* landlock_restrict_self(2): Enforces a ruleset on the calling thread
and its future children (similar to seccomp). This syscall has the
same usage restrictions as seccomp(2): the caller must have the
no_new_privs attribute set or have CAP_SYS_ADMIN in the current user
namespace.
All these syscalls have a "flags" argument (not currently used) to
enable extensibility.
Here are the motivations for these new syscalls:
* A sandboxed process may not have access to file systems, including
/dev, /sys or /proc, but it should still be able to add more
restrictions to itself.
* Neither prctl(2) nor seccomp(2) (which was used in a previous version)
fit well with the current definition of a Landlock security policy.
All passed structs (attributes) are checked at build time to ensure that
they don't contain holes and that they are aligned the same way for each
architecture.
See the user and kernel documentation for more details (provided by a
following commit):
* Documentation/userspace-api/landlock.rst
* Documentation/security/landlock.rst
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: James Morris <jmorris@namei.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Link: https://lore.kernel.org/r/20210422154123.13086-9-mic@digikod.net
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
|
|
The sb_delete security hook is called when shutting down a superblock,
which may be useful to release kernel objects tied to the superblock's
lifetime (e.g. inodes).
This new hook is needed by Landlock to release (ephemerally) tagged
struct inodes. This comes from the unprivileged nature of Landlock
described in the next commit.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Reviewed-by: Jann Horn <jannh@google.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210422154123.13086-7-mic@digikod.net
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
|
|
Using Landlock objects and ruleset, it is possible to tag inodes
according to a process's domain. To enable an unprivileged process to
express a file hierarchy, it first needs to open a directory (or a file)
and pass this file descriptor to the kernel through
landlock_add_rule(2). When checking if a file access request is
allowed, we walk from the requested dentry to the real root, following
the different mount layers. The access to each "tagged" inodes are
collected according to their rule layer level, and ANDed to create
access to the requested file hierarchy. This makes possible to identify
a lot of files without tagging every inodes nor modifying the
filesystem, while still following the view and understanding the user
has from the filesystem.
Add a new ARCH_EPHEMERAL_INODES for UML because it currently does not
keep the same struct inodes for the same inodes whereas these inodes are
in use.
This commit adds a minimal set of supported filesystem access-control
which doesn't enable to restrict all file-related actions. This is the
result of multiple discussions to minimize the code of Landlock to ease
review. Thanks to the Landlock design, extending this access-control
without breaking user space will not be a problem. Moreover, seccomp
filters can be used to restrict the use of syscall families which may
not be currently handled by Landlock.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210422154123.13086-8-mic@digikod.net
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
|