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2021-06-28Merge tag 'integrity-v5.14' of ↵Linus Torvalds
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 ...
2021-06-21evm: Check xattr size discrepancy between kernel and userRoberto Sassu
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>
2021-06-20evm: output EVM digest calculation infoMimi Zohar
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>
2021-06-16tomoyo: fix doc warningsChenXiaoSong
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>
2021-06-11IMA: support for duplicate measurement recordsTushar Sugandhi
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>
2021-06-11ima: Fix warning: no previous prototype for function 'ima_add_kexec_buffer'Lakshmi Ramasubramanian
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>
2021-06-10ima: differentiate between EVM failures in the audit logMimi Zohar
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>
2021-06-08ima: Fix fall-through warning for ClangGustavo A. R. Silva
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>
2021-06-08ima: Pass NULL instead of 0 to ima_get_action() in ima_file_mprotect()Roberto Sassu
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>
2021-06-08ima: Include header defining ima_post_key_create_or_update()Roberto Sassu
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>
2021-06-08ima/evm: Fix type mismatchRoberto Sassu
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>
2021-06-08ima: Set correct casting typesRoberto Sassu
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>
2021-06-03evm: Don't return an error in evm_write_xattrs() if audit is not enabledRoberto Sassu
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>
2021-06-03ima: Define new template evm-sigRoberto Sassu
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>
2021-06-02ima: Define new template fields xattrnames, xattrlengths and xattrvaluesRoberto Sassu
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>
2021-06-01evm: Verify portable signatures against all protected xattrsRoberto Sassu
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>
2021-06-01ima: Define new template field imodeRoberto Sassu
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>
2021-06-01ima: Define new template fields iuid and igidRoberto Sassu
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>
2021-06-01ima: Add ima_show_template_uint() template library functionRoberto Sassu
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>
2021-06-01ima: Don't remove security.ima if file must not be appraisedRoberto Sassu
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>
2021-06-01ima: Introduce template field evmsig and write to field sig as fallbackRoberto Sassu
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>
2021-06-01ima: Allow imasig requirement to be satisfied by EVM portable signaturesRoberto Sassu
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>
2021-06-01evm: Allow setxattr() and setattr() for unmodified metadataRoberto Sassu
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>
2021-05-21evm: Pass user namespace to set/remove xattr hooksRoberto Sassu
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>
2021-05-21evm: Allow xattr/attr operations for portable signaturesRoberto Sassu
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>
2021-05-21evm: Introduce evm_hmac_disabled() to safely ignore verification errorsRoberto Sassu
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>
2021-05-21evm: Introduce evm_revalidate_status()Roberto Sassu
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>
2021-05-21evm: Refuse EVM_ALLOW_METADATA_WRITES only if an HMAC key is loadedRoberto Sassu
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>
2021-05-21evm: Load EVM key in ima_load_x509() to avoid appraisalRoberto Sassu
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>
2021-05-21evm: Execute evm_inode_init_security() only when an HMAC key is loadedRoberto Sassu
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>
2021-05-20evm: fix writing <securityfs>/evm overflowMimi Zohar
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>
2021-05-12trusted-keys: match tpm_get_ops on all return pathsBen Boeckel
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>
2021-05-12KEYS: trusted: Fix memory leak on object tdColin Ian King
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>
2021-05-05Merge tag 'safesetid-5.13' of git://github.com/micah-morton/linuxLinus Torvalds
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
2021-05-02Merge branch 'work.misc' of ↵Linus Torvalds
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()
2021-05-01Merge tag 'landlock_v34' of ↵Linus Torvalds
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
2021-05-01Merge tag 'integrity-v5.13' of ↵Linus Torvalds
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
2021-04-29Merge tag 'net-next-5.13' of ↵Linus Torvalds
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 ...
2021-04-28Merge tag 'devicetree-for-5.13' of ↵Linus Torvalds
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 ...
2021-04-27Merge tag 'fixes-v5.13' of ↵Linus Torvalds
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
2021-04-27Merge tag 'selinux-pr-20210426' of ↵Linus Torvalds
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
2021-04-26LSM: SafeSetID: Fix code specification by scripts/checkpatch.plYanwei Gao
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>
2021-04-26Merge branch 'linus' of ↵Linus Torvalds
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 ...
2021-04-26Merge tag 'keys-cve-2020-26541-v3' of ↵Linus Torvalds
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
2021-04-26Merge tag 'queue' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/tpmddLinus Torvalds
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
2021-04-26Merge tag 'tpmdd-next-v5.13' of ↵Linus Torvalds
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
2021-04-22landlock: Enable user space to infer supported featuresMickaël Salaün
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>
2021-04-22landlock: Add syscall implementationsMickaël Salaün
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>
2021-04-22fs,security: Add sb_delete hookMickaël Salaün
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>
2021-04-22landlock: Support filesystem access-controlMickaël Salaün
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>