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2018-07-22EVM: fix return value check in evm_write_xattrs()Wei Yongjun1-2/+2
In case of error, the function audit_log_start() returns NULL pointer not ERR_PTR(). The IS_ERR() test in the return value check should be replaced with NULL test. Fixes: fa516b66a1bf ("EVM: Allow runtime modification of the set of verified xattrs") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-07-18evm: Allow non-SHA1 digital signaturesMatthew Garrett4-31/+46
SHA1 is reasonable in HMAC constructs, but it's desirable to be able to use stronger hashes in digital signatures. Modify the EVM crypto code so the hash type is imported from the digital signature and passed down to the hash calculation code, and return the digest size to higher layers for validation. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18evm: Don't deadlock if a crypto algorithm is unavailableMatthew Garrett1-1/+2
When EVM attempts to appraise a file signed with a crypto algorithm the kernel doesn't have support for, it will cause the kernel to trigger a module load. If the EVM policy includes appraisal of kernel modules this will in turn call back into EVM - since EVM is holding a lock until the crypto initialisation is complete, this triggers a deadlock. Add a CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag in the EVM case in order to fail gracefully with an error message instead of deadlocking. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-06-07Merge branch 'next-integrity' of ↵Linus Torvalds5-42/+271
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull integrity updates from James Morris: "From Mimi: - add run time support for specifying additional security xattrs included in the security.evm HMAC/signature - some code clean up and bug fixes" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: EVM: unlock on error path in evm_read_xattrs() EVM: prevent array underflow in evm_write_xattrs() EVM: Fix null dereference on xattr when xattr fails to allocate EVM: fix memory leak of temporary buffer 'temp' IMA: use list_splice_tail_init_rcu() instead of its open coded variant ima: use match_string() helper ima: fix updating the ima_appraise flag ima: based on policy verify firmware signatures (pre-allocated buffer) ima: define a new policy condition based on the filesystem name EVM: Allow runtime modification of the set of verified xattrs EVM: turn evm_config_xattrnames into a list integrity: Add an integrity directory in securityfs ima: Remove unused variable ima_initialized ima: Unify logging ima: Reflect correct permissions for policy
2018-06-01EVM: unlock on error path in evm_read_xattrs()Dan Carpenter1-1/+3
We need to unlock before returning on this error path. Fixes: fa516b66a1bf ("EVM: Allow runtime modification of the set of verified xattrs") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-31EVM: prevent array underflow in evm_write_xattrs()Dan Carpenter1-1/+1
If the user sets xattr->name[0] to NUL then we would read one character before the start of the array. This bug seems harmless as far as I can see but perhaps it would trigger a warning in KASAN. Fixes: fa516b66a1bf ("EVM: Allow runtime modification of the set of verified xattrs") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-31EVM: Fix null dereference on xattr when xattr fails to allocateColin Ian King1-2/+4
In the case where the allocation of xattr fails and xattr is NULL, the error exit return path via label 'out' will dereference xattr when kfree'ing xattr-name. Fix this by only kfree'ing xattr->name and xattr when xattr is non-null. Detected by CoverityScan, CID#1469366 ("Dereference after null check") Fixes: fa516b66a1bf ("EVM: Allow runtime modification of the set of verified xattrs") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-31EVM: fix memory leak of temporary buffer 'temp'Colin Ian King1-0/+2
The allocation of 'temp' is not kfree'd and hence there is a memory leak on each call of evm_read_xattrs. Fix this by kfree'ing it after copying data from it back to the user space buffer 'buf'. Detected by CoverityScan, CID#1469386 ("Resource Leak") Fixes: fa516b66a1bf ("EVM: Allow runtime modification of the set of verified xattrs") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-18EVM: Allow runtime modification of the set of verified xattrsMatthew Garrett4-4/+188
Sites may wish to provide additional metadata alongside files in order to make more fine-grained security decisions[1]. The security of this is enhanced if this metadata is protected, something that EVM makes possible. However, the kernel cannot know about the set of extended attributes that local admins may wish to protect, and hardcoding this policy in the kernel makes it difficult to change over time and less convenient for distributions to enable. This patch adds a new /sys/kernel/security/integrity/evm/evm_xattrs node, which can be read to obtain the current set of EVM-protected extended attributes or written to in order to add new entries. Extending this list will not change the validity of any existing signatures provided that the file in question does not have any of the additional extended attributes - missing xattrs are skipped when calculating the EVM hash. [1] For instance, a package manager could install information about the package uploader in an additional extended attribute. Local LSM policy could then be associated with that extended attribute in order to restrict the privileges available to packages from less trusted uploaders. Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-18EVM: turn evm_config_xattrnames into a listMatthew Garrett3-39/+57
Use a list of xattrs rather than an array - this makes it easier to extend the list at runtime. Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-17integrity: Add an integrity directory in securityfsMatthew Garrett1-3/+24
We want to add additional evm control nodes, and it'd be preferable not to clutter up the securityfs root directory any further. Create a new integrity directory, move the ima directory into it, create an evm directory for the evm attribute and add compatibility symlinks. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-03evm: Don't update hmacs in user ns mountsSeth Forshee1-1/+2
The kernel should not calculate new hmacs for mounts done by non-root users. Update evm_calc_hmac_or_hash() to refuse to calculate new hmacs for mounts for non-init user namespaces. Cc: linux-integrity@vger.kernel.org Cc: linux-security-module@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: James Morris <james.l.morris@oracle.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Dongsu Park <dongsu@kinvolk.io> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2018-03-25evm: check for remount ro in progress before writingSascha Hauer1-2/+6
EVM might update the evm xattr while the VFS performs a remount to readonly mode. This is not properly checked for, additionally check the s_readonly_remount superblock flag before writing. The bug can for example be observed with UBIFS. UBIFS checks the free space on the device before and after a remount. With EVM enabled the free space sometimes differs between both checks. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-23evm: Constify *integrity_status_msg[]Hernán Gonzalez1-1/+1
There is no gain from doing this except for some self-documenting. Signed-off-by: Hernán Gonzalez <hernan@vanguardiasur.com.ar> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-23evm: Move evm_hmac and evm_hash from evm_main.c to evm_crypto.cHernán Gonzalez3-4/+3
These variables are not used where they are was defined. There is no point in declaring them there as extern. Move and constify them, saving 2 bytes. Function old new delta init_desc 273 271 -2 Total: Before=2112094, After=2112092, chg -0.00% Signed-off-by: Hernán Gonzalez <hernan@vanguardiasur.com.ar> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-12-11EVM: Add support for portable signature formatMatthew Garrett3-20/+86
The EVM signature includes the inode number and (optionally) the filesystem UUID, making it impractical to ship EVM signatures in packages. This patch adds a new portable format intended to allow distributions to include EVM signatures. It is identical to the existing format but hardcodes the inode and generation numbers to 0 and does not include the filesystem UUID even if the kernel is configured to do so. Removing the inode means that the metadata and signature from one file could be copied to another file without invalidating it. This is avoided by ensuring that an IMA xattr is present during EVM validation. Portable signatures are intended to be immutable - ie, they will never be transformed into HMACs. Based on earlier work by Dmitry Kasatkin and Mikhail Kurinnoi. Signed-off-by: Matthew Garrett <mjg59@google.com> Cc: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Cc: Mikhail Kurinnoi <viewizard@viewizard.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-12-11EVM: Allow userland to permit modification of EVM-protected metadataMatthew Garrett3-12/+53
When EVM is enabled it forbids modification of metadata protected by EVM unless there is already a valid EVM signature. If any modification is made, the kernel will then generate a new EVM HMAC. However, this does not map well on use cases which use only asymmetric EVM signatures, as in this scenario the kernel is unable to generate new signatures. This patch extends the /sys/kernel/security/evm interface to allow userland to request that modification of these xattrs be permitted. This is only permitted if no keys have already been loaded. In this configuration, modifying the metadata will invalidate the EVM appraisal on the file in question. This allows packaging systems to write out new files, set the relevant extended attributes and then move them into place. There's also some refactoring of the use of evm_initialized in order to avoid heading down codepaths that assume there's a key available. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-11-08EVM: Only complain about a missing HMAC key onceMatthew Garrett1-1/+1
A system can validate EVM digital signatures without requiring an HMAC key, but every EVM validation will generate a kernel error. Change this so we only generate an error once. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-11-08EVM: Allow userspace to signal an RSA key has been loadedMatthew Garrett2-12/+20
EVM will only perform validation once a key has been loaded. This key may either be a symmetric trusted key (for HMAC validation and creation) or the public half of an asymmetric key (for digital signature validation). The /sys/kernel/security/evm interface allows userland to signal that a symmetric key has been loaded, but does not allow userland to signal that an asymmetric public key has been loaded. This patch extends the interface to permit userspace to pass a bitmask of loaded key types. It also allows userspace to block loading of a symmetric key in order to avoid a compromised system from being able to load an additional key type later. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-11-08EVM: Include security.apparmor in EVM measurementsMatthew Garrett1-0/+3
Apparmor will be gaining support for security.apparmor labels, and it would be helpful to include these in EVM validation now so appropriate signatures can be generated even before full support is merged. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: John Johansen <John.johansen@canonical.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-05fs: switch ->s_uuid to uuid_tChristoph Hellwig1-1/+1
For some file systems we still memcpy into it, but in various places this already allows us to use the proper uuid helpers. More to come.. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM) Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-03-02sched/headers: Prepare to remove the <linux/magic.h> include from ↵Ingo Molnar1-0/+2
<linux/sched/task_stack.h> Update files that depend on the magic.h inclusion. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-14Merge branch 'for-linus' of ↵Linus Torvalds1-2/+10
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull namespace updates from Eric Biederman: "After a lot of discussion and work we have finally reachanged a basic understanding of what is necessary to make unprivileged mounts safe in the presence of EVM and IMA xattrs which the last commit in this series reflects. While technically it is a revert the comments it adds are important for people not getting confused in the future. Clearing up that confusion allows us to seriously work on unprivileged mounts of fuse in the next development cycle. The rest of the fixes in this set are in the intersection of user namespaces, ptrace, and exec. I started with the first fix which started a feedback cycle of finding additional issues during review and fixing them. Culiminating in a fix for a bug that has been present since at least Linux v1.0. Potentially these fixes were candidates for being merged during the rc cycle, and are certainly backport candidates but enough little things turned up during review and testing that I decided they should be handled as part of the normal development process just to be certain there were not any great surprises when it came time to backport some of these fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: Revert "evm: Translate user/group ids relative to s_user_ns when computing HMAC" exec: Ensure mm->user_ns contains the execed files ptrace: Don't allow accessing an undumpable mm ptrace: Capture the ptracer's creds not PT_PTRACE_CAP mm: Add a user_ns owner to mm_struct and fix ptrace permission checks
2016-12-02Revert "evm: Translate user/group ids relative to s_user_ns when computing HMAC"Eric W. Biederman1-2/+10
This reverts commit 0b3c9761d1e405514a551ed24d3ea89aea26ce14. Seth Forshee <seth.forshee@canonical.com> writes: > All right, I think 0b3c9761d1e405514a551ed24d3ea89aea26ce14 should be > reverted then. EVM is a machine-local integrity mechanism, and so it > makes sense that the signature would be based on the kernel's notion of > the uid and not the filesystem's. I added a commment explaining why the EVM hmac needs to be in the kernel's notion of uid and gid, not the filesystems to prevent remounting the filesystem and gaining unwaranted trust in files. Acked-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-11-13security/integrity: Harden against malformed xattrsSeth Forshee1-0/+4
In general the handling of IMA/EVM xattrs is good, but I found a few locations where either the xattr size or the value of the type field in the xattr are not checked. Add a few simple checks to these locations to prevent malformed or malicious xattrs from causing problems. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-10-07xattr: Add __vfs_{get,set,remove}xattr helpersAndreas Gruenbacher2-5/+6
Right now, various places in the kernel check for the existence of getxattr, setxattr, and removexattr inode operations and directly call those operations. Switch to helper functions and test for the IOP_XATTR flag instead. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05evm: Translate user/group ids relative to s_user_ns when computing HMACSeth Forshee1-2/+2
The EVM HMAC should be calculated using the on disk user and group ids, so the k[ug]ids in the inode must be translated relative to the s_user_ns of the inode's super block. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-04-11->getxattr(): pass dentry and inode as separate argumentsAl Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-10don't bother with ->d_inode->i_sb - it's always equal to ->d_sbAl Viro1-2/+2
... and neither can ever be NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-02-12EVM: Use crypto_memneq() for digest comparisonsRyan Ware1-1/+2
This patch fixes vulnerability CVE-2016-2085. The problem exists because the vm_verify_hmac() function includes a use of memcmp(). Unfortunately, this allows timing side channel attacks; specifically a MAC forgery complexity drop from 2^128 to 2^12. This patch changes the memcmp() to the cryptographically safe crypto_memneq(). Reported-by: Xiaofei Rex Guo <xiaofei.rex.guo@intel.com> Signed-off-by: Ryan Ware <ware@linux.intel.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2015-12-15evm: EVM_LOAD_X509 depends on EVMArnd Bergmann1-1/+1
The newly added EVM_LOAD_X509 code can be configured even if CONFIG_EVM is disabled, but that causes a link error: security/built-in.o: In function `integrity_load_keys': digsig_asymmetric.c:(.init.text+0x400): undefined reference to `evm_load_x509' This adds a Kconfig dependency to ensure it is only enabled when CONFIG_EVM is set as well. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 2ce523eb8976 ("evm: load x509 certificate from the kernel") Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15evm: reset EVM status when file attributes changeDmitry Kasatkin1-0/+13
The EVM verification status is cached in iint->evm_status and if it was successful, never re-verified again when IMA passes the 'iint' to evm_verifyxattr(). When file attributes or extended attributes change, we may wish to re-verify EVM integrity as well. For example, after setting a digital signature we may need to re-verify the signature and update the iint->flags that there is an EVM signature. This patch enables that by resetting evm_status to INTEGRITY_UKNOWN state. Changes in v2: * Flag setting moved to EVM layer Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15evm: provide a function to set the EVM key from the kernelDmitry Kasatkin2-14/+46
A crypto HW kernel module can possibly initialize the EVM key from the kernel __init code to enable EVM before calling the 'init' process. This patch provides a function evm_set_key() to set the EVM key directly without using the KEY subsystem. Changes in v4: * kernel-doc style for evm_set_key Changes in v3: * error reporting moved to evm_set_key * EVM_INIT_HMAC moved to evm_set_key * added bitop to prevent key setting race Changes in v2: * use size_t for key size instead of signed int * provide EVM_MAX_KEY_SIZE macro in <linux/evm.h> * provide EVM_MIN_KEY_SIZE macro in <linux/evm.h> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15evm: enable EVM when X509 certificate is loadedDmitry Kasatkin4-3/+14
In order to enable EVM before starting the 'init' process, evm_initialized needs to be non-zero. Previously non-zero indicated that the HMAC key was loaded. When EVM loads the X509 before calling 'init', with this patch it is now possible to enable EVM to start signature based verification. This patch defines bits to enable EVM if a key of any type is loaded. Changes in v3: * print error message if key is not set Changes in v2: * EVM_STATE_KEY_SET replaced by EVM_INIT_HMAC * EVM_STATE_X509_SET replaced by EVM_INIT_X509 Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15evm: load an x509 certificate from the kernelDmitry Kasatkin2-0/+24
This patch defines a configuration option and the evm_load_x509() hook to load an X509 certificate onto the EVM trusted kernel keyring. Changes in v4: * Patch description updated Changes in v3: * Removed EVM_X509_PATH definition. CONFIG_EVM_X509_PATH is used directly. Changes in v2: * default key patch changed to /etc/keys Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-11-23integrity: define '.evm' as a builtin 'trusted' keyringDmitry Kasatkin1-3/+5
Require all keys added to the EVM keyring be signed by an existing trusted key on the system trusted keyring. This patch also switches IMA to use integrity_init_keyring(). Changes in v3: * Added 'init_keyring' config based variable to skip initializing keyring instead of using __integrity_init_keyring() wrapper. * Added dependency back to CONFIG_IMA_TRUSTED_KEYRING Changes in v2: * Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option * Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config file compatibility. (Mimi Zohar) Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-10-21KEYS: Merge the type-specific data with the payload dataDavid Howells1-1/+1
Merge the type-specific data with the payload data into one four-word chunk as it seems pointless to keep them separate. Use user_key_payload() for accessing the payloads of overloaded user-defined keys. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cifs@vger.kernel.org cc: ecryptfs@vger.kernel.org cc: linux-ext4@vger.kernel.org cc: linux-f2fs-devel@lists.sourceforge.net cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: linux-ima-devel@lists.sourceforge.net
2015-05-21evm: fix potential race when removing xattrsDmitry Kasatkin1-4/+3
EVM needs to be atomically updated when removing xattrs. Otherwise concurrent EVM verification may fail in between. This patch fixes by moving i_mutex unlocking after calling EVM hook. fsnotify_xattr() is also now called while locked the same way as it is done in __vfs_setxattr_noperm. Changelog: - remove unused 'inode' variable. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-05-21evm: labeling pseudo filesystems exceptionMimi Zohar1-0/+11
To prevent offline stripping of existing file xattrs and relabeling of them at runtime, EVM allows only newly created files to be labeled. As pseudo filesystems are not persistent, stripping of xattrs is not a concern. Some LSMs defer file labeling on pseudo filesystems. This patch permits the labeling of existing files on pseudo files systems. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-04-15VFS: security/: d_backing_inode() annotationsDavid Howells2-11/+11
most of the ->d_inode uses there refer to the same inode IO would go to, i.e. d_backing_inode() Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-01-07kconfig: use bool instead of boolean for type definition attributesChristoph Jaeger1-1/+1
Support for keyword 'boolean' will be dropped later on. No functional change. Reference: http://lkml.kernel.org/r/cover.1418003065.git.cj@linux.com Signed-off-by: Christoph Jaeger <cj@linux.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-12-14Merge branch 'next' of ↵Linus Torvalds1-3/+8
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: "In terms of changes, there's general maintenance to the Smack, SELinux, and integrity code. The IMA code adds a new kconfig option, IMA_APPRAISE_SIGNED_INIT, which allows IMA appraisal to require signatures. Support for reading keys from rootfs before init is call is also added" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits) selinux: Remove security_ops extern security: smack: fix out-of-bounds access in smk_parse_smack() VFS: refactor vfs_read() ima: require signature based appraisal integrity: provide a hook to load keys when rootfs is ready ima: load x509 certificate from the kernel integrity: provide a function to load x509 certificate from the kernel integrity: define a new function integrity_read_file() Security: smack: replace kzalloc with kmem_cache for inode_smack Smack: Lock mode for the floor and hat labels ima: added support for new kernel cmdline parameter ima_template_fmt ima: allocate field pointers array on demand in template_desc_init_fields() ima: don't allocate a copy of template_fmt in template_desc_init_fields() ima: display template format in meas. list if template name length is zero ima: added error messages to template-related functions ima: use atomic bit operations to protect policy update interface ima: ignore empty and with whitespaces policy lines ima: no need to allocate entry for comment ima: report policy load status ima: use path names cache ...
2014-10-28evm: check xattr value length and type in evm_inode_setxattr()Dmitry Kasatkin1-3/+6
evm_inode_setxattr() can be called with no value. The function does not check the length so that following command can be used to produce the kernel oops: setfattr -n security.evm FOO. This patch fixes it. Changes in v3: * there is no reason to return different error codes for EVM_XATTR_HMAC and non EVM_XATTR_HMAC. Remove unnecessary test then. Changes in v2: * testing for validity of xattr type [ 1106.396921] BUG: unable to handle kernel NULL pointer dereference at (null) [ 1106.398192] IP: [<ffffffff812af7b8>] evm_inode_setxattr+0x2a/0x48 [ 1106.399244] PGD 29048067 PUD 290d7067 PMD 0 [ 1106.399953] Oops: 0000 [#1] SMP [ 1106.400020] Modules linked in: bridge stp llc evdev serio_raw i2c_piix4 button fuse [ 1106.400020] CPU: 0 PID: 3635 Comm: setxattr Not tainted 3.16.0-kds+ #2936 [ 1106.400020] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 1106.400020] task: ffff8800291a0000 ti: ffff88002917c000 task.ti: ffff88002917c000 [ 1106.400020] RIP: 0010:[<ffffffff812af7b8>] [<ffffffff812af7b8>] evm_inode_setxattr+0x2a/0x48 [ 1106.400020] RSP: 0018:ffff88002917fd50 EFLAGS: 00010246 [ 1106.400020] RAX: 0000000000000000 RBX: ffff88002917fdf8 RCX: 0000000000000000 [ 1106.400020] RDX: 0000000000000000 RSI: ffffffff818136d3 RDI: ffff88002917fdf8 [ 1106.400020] RBP: ffff88002917fd68 R08: 0000000000000000 R09: 00000000003ec1df [ 1106.400020] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800438a0a00 [ 1106.400020] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 1106.400020] FS: 00007f7dfa7d7740(0000) GS:ffff88005da00000(0000) knlGS:0000000000000000 [ 1106.400020] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1106.400020] CR2: 0000000000000000 CR3: 000000003763e000 CR4: 00000000000006f0 [ 1106.400020] Stack: [ 1106.400020] ffff8800438a0a00 ffff88002917fdf8 0000000000000000 ffff88002917fd98 [ 1106.400020] ffffffff812a1030 ffff8800438a0a00 ffff88002917fdf8 0000000000000000 [ 1106.400020] 0000000000000000 ffff88002917fde0 ffffffff8116d08a ffff88002917fdc8 [ 1106.400020] Call Trace: [ 1106.400020] [<ffffffff812a1030>] security_inode_setxattr+0x5d/0x6a [ 1106.400020] [<ffffffff8116d08a>] vfs_setxattr+0x6b/0x9f [ 1106.400020] [<ffffffff8116d1e0>] setxattr+0x122/0x16c [ 1106.400020] [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45 [ 1106.400020] [<ffffffff8114d011>] ? __sb_start_write+0x10f/0x143 [ 1106.400020] [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45 [ 1106.400020] [<ffffffff811687c0>] ? __mnt_want_write+0x48/0x4f [ 1106.400020] [<ffffffff8116d3e6>] SyS_setxattr+0x6e/0xb0 [ 1106.400020] [<ffffffff81529da9>] system_call_fastpath+0x16/0x1b [ 1106.400020] Code: c3 0f 1f 44 00 00 55 48 89 e5 41 55 49 89 d5 41 54 49 89 fc 53 48 89 f3 48 c7 c6 d3 36 81 81 48 89 df e8 18 22 04 00 85 c0 75 07 <41> 80 7d 00 02 74 0d 48 89 de 4c 89 e7 e8 5a fe ff ff eb 03 83 [ 1106.400020] RIP [<ffffffff812af7b8>] evm_inode_setxattr+0x2a/0x48 [ 1106.400020] RSP <ffff88002917fd50> [ 1106.400020] CR2: 0000000000000000 [ 1106.428061] ---[ end trace ae08331628ba3050 ]--- Reported-by: Jan Kara <jack@suse.cz> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-07evm: skip replacing EVM signature with HMAC on read-only filesystemDmitry Kasatkin1-3/+8
If filesystem is mounted read-only or file is immutable, updating xattr will fail. This is a usual case during early boot until filesystem is remount read-write. This patch verifies conditions to skip unnecessary attempt to calculate HMAC and set xattr. Changes in v2: * indention changed according to Lindent (requested by Mimi) Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09integrity: base integrity subsystem kconfig options on integrityDmitry Kasatkin1-8/+0
The integrity subsystem has lots of options and takes more than half of the security menu. This patch consolidates the options under "integrity", which are hidden if not enabled. This change does not affect existing configurations. Re-configuration is not needed. Changes v4: - no need to change "integrity subsystem" to menuconfig as options are hidden, when not enabled. (Mimi) - add INTEGRITY Kconfig help description Changes v3: - dependency to INTEGRITY removed when behind 'if INTEGRITY' Changes v2: - previous patch moved integrity out of the 'security' menu. This version keeps integrity as a security option (Mimi). Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09evm: properly handle INTEGRITY_NOXATTRS EVM statusDmitry Kasatkin1-0/+7
Unless an LSM labels a file during d_instantiate(), newly created files are not labeled with an initial security.evm xattr, until the file closes. EVM, before allowing a protected, security xattr to be written, verifies the existing 'security.evm' value is good. For newly created files without a security.evm label, this verification prevents writing any protected, security xattrs, until the file closes. Following is the example when this happens: fd = open("foo", O_CREAT | O_WRONLY, 0644); setxattr("foo", "security.SMACK64", value, sizeof(value), 0); close(fd); While INTEGRITY_NOXATTRS status is handled in other places, such as evm_inode_setattr(), it does not handle it in all cases in evm_protect_xattr(). By limiting the use of INTEGRITY_NOXATTRS to newly created files, we can now allow setting "protected" xattrs. Changelog: - limit the use of INTEGRITY_NOXATTRS to IMA identified new files Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> 3.14+
2014-09-08evm: prevent passing integrity check if xattr read failsDmitry Kasatkin1-3/+4
This patch fixes a bug, where evm_verify_hmac() returns INTEGRITY_PASS if inode->i_op->getxattr() returns an error in evm_find_protected_xattrs. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
2014-09-02evm: fix checkpatch warningsDmitry Kasatkin1-3/+0
This patch fixes checkpatch 'return' warnings introduced with commit 9819cf2 "checkpatch: warn on unnecessary void function return statements". Use scripts/checkpatch.pl --file security/integrity/evm/evm_main.c to produce the warnings. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-06-12evm: prohibit userspace writing 'security.evm' HMAC valueMimi Zohar1-2/+10
Calculating the 'security.evm' HMAC value requires access to the EVM encrypted key. Only the kernel should have access to it. This patch prevents userspace tools(eg. setfattr, cp --preserve=xattr) from setting/modifying the 'security.evm' HMAC value directly. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org>
2014-06-12evm: provide option to protect additional SMACK xattrsDmitry Kasatkin2-0/+22
Newer versions of SMACK introduced following security xattrs: SMACK64EXEC, SMACK64TRANSMUTE and SMACK64MMAP. To protect these xattrs, this patch includes them in the HMAC calculation. However, for backwards compatibility with existing labeled filesystems, including these xattrs needs to be configurable. Changelog: - Add SMACK dependency on new option (Mimi) Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>