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2016-10-07xattr: Add __vfs_{get,set,remove}xattr helpersAndreas Gruenbacher
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 Forshee
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 Viro
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 Viro
... 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 Ware
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 Bergmann
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Howells
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 Kasatkin
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 Zohar
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 Howells
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 Jaeger
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 Torvalds
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Kasatkin
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 Zohar
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 Kasatkin
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>
2014-06-12evm: replace HMAC version with attribute maskDmitry Kasatkin
Using HMAC version limits the posibility to arbitrarily add new attributes such as SMACK64EXEC to the hmac calculation. This patch replaces hmac version with attribute mask. Desired attributes can be enabled with configuration parameter. It allows to build kernels which works with previously labeled filesystems. Currently supported attribute is 'fsuuid' which is equivalent of the former version 2. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-04-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "The first vfs pile, with deep apologies for being very late in this window. Assorted cleanups and fixes, plus a large preparatory part of iov_iter work. There's a lot more of that, but it'll probably go into the next merge window - it *does* shape up nicely, removes a lot of boilerplate, gets rid of locking inconsistencie between aio_write and splice_write and I hope to get Kent's direct-io rewrite merged into the same queue, but some of the stuff after this point is having (mostly trivial) conflicts with the things already merged into mainline and with some I want more testing. This one passes LTP and xfstests without regressions, in addition to usual beating. BTW, readahead02 in ltp syscalls testsuite has started giving failures since "mm/readahead.c: fix readahead failure for memoryless NUMA nodes and limit readahead pages" - might be a false positive, might be a real regression..." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) missing bits of "splice: fix racy pipe->buffers uses" cifs: fix the race in cifs_writev() ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure kill generic_file_buffered_write() ocfs2_file_aio_write(): switch to generic_perform_write() ceph_aio_write(): switch to generic_perform_write() xfs_file_buffered_aio_write(): switch to generic_perform_write() export generic_perform_write(), start getting rid of generic_file_buffer_write() generic_file_direct_write(): get rid of ppos argument btrfs_file_aio_write(): get rid of ppos kill the 5th argument of generic_file_buffered_write() kill the 4th argument of __generic_file_aio_write() lustre: don't open-code kernel_recvmsg() ocfs2: don't open-code kernel_recvmsg() drbd: don't open-code kernel_recvmsg() constify blk_rq_map_user_iov() and friends lustre: switch to kernel_sendmsg() ocfs2: don't open-code kernel_sendmsg() take iov_iter stuff to mm/iov_iter.c process_vm_access: tidy up a bit ...
2014-04-01get rid of pointless checks for NULL ->i_opAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-07evm: enable key retention service automaticallyDmitry Kasatkin
If keys are not enabled, EVM is not visible in the configuration menu. It may be difficult to figure out what to do unless you really know. Other subsystems as NFS, CIFS select keys automatically. This patch does the same. This patch also removes '(TRUSTED_KEYS=y || TRUSTED_KEYS=n)' dependency, which is unnecessary. EVM does not depend on trusted keys, but on encrypted keys. evm.h provides compile time dependency. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07evm: EVM does not use MD5Dmitry Kasatkin
EVM does not use MD5 HMAC. Selection of CRYPTO_MD5 can be safely removed. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07integrity: fix checkpatch errorsDmitry Kasatkin
Between checkpatch changes (eg. sizeof) and inconsistencies between Lindent and checkpatch, unfixed checkpatch errors make it difficult to see new errors. This patch fixes them. Some lines with over 80 chars remained unchanged to improve code readability. The "extern" keyword is removed from internal evm.h to make it consistent with internal ima.h. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-03-07security: integrity: Use a more current logging styleJoe Perches
Convert printks to pr_<level>. Add pr_fmt. Remove embedded prefixes. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-10-25ima: pass full xattr with the signatureDmitry Kasatkin
For possibility to use xattr type for new signature formats, pass full xattr to the signature verification function. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-10-25ima: fix script messagesDmitry Kasatkin
Fix checkpatch, lindent, etc, warnings/errors Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-07-25xattr: Constify ->name member of "struct xattr".Tetsuo Handa
Since everybody sets kstrdup()ed constant string to "struct xattr"->name but nobody modifies "struct xattr"->name , we can omit kstrdup() and its failure checking by constifying ->name member of "struct xattr". Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Joel Becker <jlbec@evilplan.org> [ocfs2] Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Paul Moore <paul@paul-moore.com> Tested-by: Paul Moore <paul@paul-moore.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-06-20evm: audit integrity metadata failuresMimi Zohar
Before modifying an EVM protected extended attribute or any other metadata included in the HMAC calculation, the existing 'security.evm' is verified. This patch adds calls to integrity_audit_msg() to audit integrity metadata failures. Reported-by: Sven Vermeulen <sven.vermeulen@siphos.be> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-02-21Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "This is basically a maintenance update for the TPM driver and EVM/IMA" Fix up conflicts in lib/digsig.c and security/integrity/ima/ima_main.c * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (45 commits) tpm/ibmvtpm: build only when IBM pseries is configured ima: digital signature verification using asymmetric keys ima: rename hash calculation functions ima: use new crypto_shash API instead of old crypto_hash ima: add policy support for file system uuid evm: add file system uuid to EVM hmac tpm_tis: check pnp_acpi_device return code char/tpm/tpm_i2c_stm_st33: drop temporary variable for return value char/tpm/tpm_i2c_stm_st33: remove dead assignment in tpm_st33_i2c_probe char/tpm/tpm_i2c_stm_st33: Remove __devexit attribute char/tpm/tpm_i2c_stm_st33: Don't use memcpy for one byte assignment tpm_i2c_stm_st33: removed unused variables/code TPM: Wait for TPM_ACCESS tpmRegValidSts to go high at startup tpm: Fix cancellation of TPM commands (interrupt mode) tpm: Fix cancellation of TPM commands (polling mode) tpm: Store TPM vendor ID TPM: Work around buggy TPMs that block during continue self test tpm_i2c_stm_st33: fix oops when i2c client is unavailable char/tpm: Use struct dev_pm_ops for power management TPM: STMicroelectronics ST33 I2C BUILD STUFF ...
2013-02-06evm: add file system uuid to EVM hmacDmitry Kasatkin
EVM uses the same key for all file systems to calculate the HMAC, making it possible to paste inodes from one file system on to another one, without EVM being able to detect it. To prevent such an attack, it is necessary to make the EVM HMAC file system specific. This patch uses the file system UUID, a file system unique identifier, to bind the EVM HMAC to the file system. The value inode->i_sb->s_uuid is used for the HMAC hash calculation, instead of using it for deriving the file system specific key. Initializing the key for every inode HMAC calculation is a bit more expensive operation than adding the uuid to the HMAC hash. Changing the HMAC calculation method or adding additional info to the calculation, requires existing EVM labeled file systems to be relabeled. This patch adds a Kconfig HMAC version option for backwards compatability. Changelog v1: - squash "hmac version setting" Changelog v0: - add missing Kconfig depends (Mimi) Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2013-01-22evm: checking if removexattr is not a NULLDmitry Kasatkin
The following lines of code produce a kernel oops. fd = socket(PF_FILE, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); fchmod(fd, 0666); [ 139.922364] BUG: unable to handle kernel NULL pointer dereference at (null) [ 139.924982] IP: [< (null)>] (null) [ 139.924982] *pde = 00000000 [ 139.924982] Oops: 0000 [#5] SMP [ 139.924982] Modules linked in: fuse dm_crypt dm_mod i2c_piix4 serio_raw evdev binfmt_misc button [ 139.924982] Pid: 3070, comm: acpid Tainted: G D 3.8.0-rc2-kds+ #465 Bochs Bochs [ 139.924982] EIP: 0060:[<00000000>] EFLAGS: 00010246 CPU: 0 [ 139.924982] EIP is at 0x0 [ 139.924982] EAX: cf5ef000 EBX: cf5ef000 ECX: c143d600 EDX: c15225f2 [ 139.924982] ESI: cf4d2a1c EDI: cf4d2a1c EBP: cc02df10 ESP: cc02dee4 [ 139.924982] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 139.924982] CR0: 80050033 CR2: 00000000 CR3: 0c059000 CR4: 000006d0 [ 139.924982] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 139.924982] DR6: ffff0ff0 DR7: 00000400 [ 139.924982] Process acpid (pid: 3070, ti=cc02c000 task=d7705340 task.ti=cc02c000) [ 139.924982] Stack: [ 139.924982] c1203c88 00000000 cc02def4 cf4d2a1c ae21eefa 471b60d5 1083c1ba c26a5940 [ 139.924982] e891fb5e 00000041 00000004 cc02df1c c1203964 00000000 cc02df4c c10e20c3 [ 139.924982] 00000002 00000000 00000000 22222222 c1ff2222 cf5ef000 00000000 d76efb08 [ 139.924982] Call Trace: [ 139.924982] [<c1203c88>] ? evm_update_evmxattr+0x5b/0x62 [ 139.924982] [<c1203964>] evm_inode_post_setattr+0x22/0x26 [ 139.924982] [<c10e20c3>] notify_change+0x25f/0x281 [ 139.924982] [<c10cbf56>] chmod_common+0x59/0x76 [ 139.924982] [<c10e27a1>] ? put_unused_fd+0x33/0x33 [ 139.924982] [<c10cca09>] sys_fchmod+0x39/0x5c [ 139.924982] [<c13f4f30>] syscall_call+0x7/0xb [ 139.924982] Code: Bad EIP value. This happens because sockets do not define the removexattr operation. Before removing the xattr, verify the removexattr function pointer is not NULL. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: James Morris <james.l.morris@oracle.com>
2013-01-16evm: remove unused cleanup functionsDmitry Kasatkin
EVM cannot be built as a kernel module. Remove the unncessary __exit functions. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2012-10-02Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Highlights: - Integrity: add local fs integrity verification to detect offline attacks - Integrity: add digital signature verification - Simple stacking of Yama with other LSMs (per LSS discussions) - IBM vTPM support on ppc64 - Add new driver for Infineon I2C TIS TPM - Smack: add rule revocation for subject labels" Fixed conflicts with the user namespace support in kernel/auditsc.c and security/integrity/ima/ima_policy.c. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (39 commits) Documentation: Update git repository URL for Smack userland tools ima: change flags container data type Smack: setprocattr memory leak fix Smack: implement revoking all rules for a subject label Smack: remove task_wait() hook. ima: audit log hashes ima: generic IMA action flag handling ima: rename ima_must_appraise_or_measure audit: export audit_log_task_info tpm: fix tpm_acpi sparse warning on different address spaces samples/seccomp: fix 31 bit build on s390 ima: digital signature verification support ima: add support for different security.ima data types ima: add ima_inode_setxattr/removexattr function and calls ima: add inode_post_setattr call ima: replace iint spinblock with rwlock/read_lock ima: allocating iint improvements ima: add appraise action keywords and default rules ima: integrity appraisal extension vfs: move ima_file_free before releasing the file ...
2012-09-21userns: Convert EVM to deal with kuids and kgids in it's hmac computationEric W. Biederman
Cc: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-07ima: integrity appraisal extensionMimi Zohar
IMA currently maintains an integrity measurement list used to assert the integrity of the running system to a third party. The IMA-appraisal extension adds local integrity validation and enforcement of the measurement against a "good" value stored as an extended attribute 'security.ima'. The initial methods for validating 'security.ima' are hashed based, which provides file data integrity, and digital signature based, which in addition to providing file data integrity, provides authenticity. This patch creates and maintains the 'security.ima' xattr, containing the file data hash measurement. Protection of the xattr is provided by EVM, if enabled and configured. Based on policy, IMA calls evm_verifyxattr() to verify a file's metadata integrity and, assuming success, compares the file's current hash value with the one stored as an extended attribute in 'security.ima'. Changelov v4: - changed iint cache flags to hex values Changelog v3: - change appraisal default for filesystems without xattr support to fail Changelog v2: - fix audit msg 'res' value - removed unused 'ima_appraise=' values Changelog v1: - removed unused iint mutex (Dmitry Kasatkin) - setattr hook must not reset appraised (Dmitry Kasatkin) - evm_verifyxattr() now differentiates between no 'security.evm' xattr (INTEGRITY_NOLABEL) and no EVM 'protected' xattrs included in the 'security.evm' (INTEGRITY_NOXATTRS). - replace hash_status with ima_status (Dmitry Kasatkin) - re-initialize slab element ima_status on free (Dmitry Kasatkin) - include 'security.ima' in EVM if CONFIG_IMA_APPRAISE, not CONFIG_IMA - merged half "ima: ima_must_appraise_or_measure API change" (Dmitry Kasatkin) - removed unnecessary error variable in process_measurement() (Dmitry Kasatkin) - use ima_inode_post_setattr() stub function, if IMA_APPRAISE not configured (moved ima_inode_post_setattr() to ima_appraise.c) - make sure ima_collect_measurement() can read file Changelog: - add 'iint' to evm_verifyxattr() call (Dimitry Kasatkin) - fix the race condition between chmod, which takes the i_mutex and then iint->mutex, and ima_file_free() and process_measurement(), which take the locks in the reverse order, by eliminating iint->mutex. (Dmitry Kasatkin) - cleanup of ima_appraise_measurement() (Dmitry Kasatkin) - changes as a result of the iint not allocated for all regular files, but only for those measured/appraised. - don't try to appraise new/empty files - expanded ima_appraisal description in ima/Kconfig - IMA appraise definitions required even if IMA_APPRAISE not enabled - add return value to ima_must_appraise() stub - unconditionally set status = INTEGRITY_PASS *after* testing status, not before. (Found by Joe Perches) Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
2012-01-09Merge branch 'next' into for-linusJames Morris
Conflicts: security/integrity/evm/evm_crypto.c Resolved upstream fix vs. next conflict manually. Signed-off-by: James Morris <jmorris@namei.org>
2011-12-20evm: prevent racing during tfm allocationDmitry Kasatkin
There is a small chance of racing during tfm allocation. This patch fixes it. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-12-20evm: key must be set once during initializationDmitry Kasatkin
On multi-core systems, setting of the key before every caclculation, causes invalid HMAC calculation for other tfm users, because internal state (ipad, opad) can be invalid before set key call returns. It needs to be set only once during initialization. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-12-08evm: prevent racing during tfm allocationDmitry Kasatkin
There is a small chance of racing during tfm allocation. This patch fixes it. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-12-08evm: key must be set once during initializationDmitry Kasatkin
On multi-core systems, setting of the key before every caclculation, causes invalid HMAC calculation for other tfm users, because internal state (ipad, opad) can be invalid before set key call returns. It needs to be set only once during initialization. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-11-09evm: digital signature verification supportDmitry Kasatkin
This patch adds support for digital signature verification to EVM. With this feature file metadata can be protected using digital signature instead of an HMAC. When building an image, which has to be flashed to different devices, an HMAC cannot be used to sign file metadata, because the HMAC key should be different on every device. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14evm: permit mode bits to be updatedMimi Zohar
Before permitting 'security.evm' to be updated, 'security.evm' must exist and be valid. In the case that there are no existing EVM protected xattrs, it is safe for posix acls to update the mode bits. To differentiate between no 'security.evm' xattr and no xattrs used to calculate 'security.evm', this patch defines INTEGRITY_NOXATTR. Signed-off-by: Mimi Zohar <zohar@us.ibm.com>