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2018-08-15Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-securityLinus Torvalds2-3/+7
Pull integrity updates from James Morris: "This adds support for EVM signatures based on larger digests, contains a new audit record AUDIT_INTEGRITY_POLICY_RULE to differentiate the IMA policy rules from the IMA-audit messages, addresses two deadlocks due to either loading or searching for crypto algorithms, and cleans up the audit messages" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: EVM: fix return value check in evm_write_xattrs() integrity: prevent deadlock during digsig verification. evm: Allow non-SHA1 digital signatures evm: Don't deadlock if a crypto algorithm is unavailable integrity: silence warning when CONFIG_SECURITYFS is not enabled ima: Differentiate auditing policy rules from "audit" actions ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not set ima: Use audit_log_format() rather than audit_log_string() ima: Call audit_log_string() rather than logging it untrusted
2018-08-15Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-securityLinus Torvalds4-16/+10
Pull TPM updates from James Morris: - Migrate away from PM runtime as explicit cmdReady/goIdle transactions for every command is a spec requirement. PM runtime adds only a layer of complexity on our case. - tpm_tis drivers can now specify the hwrng quality. - TPM 2.0 code uses now tpm_buf for constructing messages. Jarkko thinks Tomas Winkler has done the same for TPM 1.2, and will start digging those changes from the patchwork in the near future. - Bug fixes and clean ups * 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: ima: Get rid of ima_used_chip and use ima_tpm_chip != NULL instead ima: Use tpm_default_chip() and call TPM functions with a tpm_chip tpm: replace TPM_TRANSMIT_RAW with TPM_TRANSMIT_NESTED tpm: Convert tpm_find_get_ops() to use tpm_default_chip() tpm: Implement tpm_default_chip() to find a TPM chip tpm: rename tpm_chip_find_get() to tpm_find_get_ops() tpm: Allow tpm_tis drivers to set hwrng quality. tpm: Return the actual size when receiving an unsupported command tpm: separate cmd_ready/go_idle from runtime_pm tpm/tpm_i2c_infineon: switch to i2c_lock_bus(..., I2C_LOCK_SEGMENT) tpm_tis_spi: Pass the SPI IRQ down to the driver tpm: migrate tpm2_get_random() to use struct tpm_buf tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf tpm: migrate tpm2_probe() to use struct tpm_buf tpm: migrate tpm2_shutdown() to use struct tpm_buf
2018-08-15Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-securityLinus Torvalds4-17/+158
Pull security subsystem updates from James Morris: - kstrdup() return value fix from Eric Biggers - Add new security_load_data hook to differentiate security checking of kernel-loaded binaries in the case of there being no associated file descriptor, from Mimi Zohar. - Add ability to IMA to specify a policy at build-time, rather than just via command line params or by loading a custom policy, from Mimi. - Allow IMA and LSMs to prevent sysfs firmware load fallback (e.g. if using signed firmware), from Mimi. - Allow IMA to deny loading of kexec kernel images, as they cannot be measured by IMA, from Mimi. * 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: security: check for kstrdup() failure in lsm_append() security: export security_kernel_load_data function ima: based on policy warn about loading firmware (pre-allocated buffer) module: replace the existing LSM hook in init_module ima: add build time policy ima: based on policy require signed firmware (sysfs fallback) firmware: add call to LSM hook before firmware sysfs fallback ima: based on policy require signed kexec kernel images kexec: add call to LSM hook in original kexec_load syscall security: define new LSM hook named security_kernel_load_data MAINTAINERS: remove the outdated "LINUX SECURITY MODULE (LSM) FRAMEWORK" entry
2018-07-28ima: Get rid of ima_used_chip and use ima_tpm_chip != NULL insteadStefan Berger4-8/+4
Get rid of ima_used_chip and use ima_tpm_chip variable instead for determining whether to use the TPM chip. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-07-28ima: Use tpm_default_chip() and call TPM functions with a tpm_chipStefan Berger4-9/+7
Rather than accessing the TPM functions by passing a NULL pointer for the tpm_chip, which causes a lookup for a suitable chip every time, get a hold of a tpm_chip and access the TPM functions using it. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-07-18ima: Differentiate auditing policy rules from "audit" actionsStefan Berger1-2/+2
The AUDIT_INTEGRITY_RULE is used for auditing IMA policy rules and the IMA "audit" policy action. This patch defines AUDIT_INTEGRITY_POLICY_RULE to reflect the IMA policy rules. Since we defined a new message type we can now also pass the audit_context and get an associated SYSCALL record. This now produces the following records when parsing IMA policy's rules: type=UNKNOWN[1807] msg=audit(1527888965.738:320): action=audit \ func=MMAP_CHECK mask=MAY_EXEC res=1 type=UNKNOWN[1807] msg=audit(1527888965.738:320): action=audit \ func=FILE_CHECK mask=MAY_READ res=1 type=SYSCALL msg=audit(1527888965.738:320): arch=c000003e syscall=1 \ success=yes exit=17 a0=1 a1=55bcfcca9030 a2=11 a3=7fcc1b55fb38 \ items=0 ppid=1567 pid=1601 auid=0 uid=0 gid=0 euid=0 suid=0 \ fsuid=0 egid=0 sgid=0 fsgid=0 tty=tty2 ses=2 comm="echo" \ exe="/usr/bin/echo" \ subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not setStefan Berger2-1/+6
If Integrity is not auditing, IMA shouldn't audit, either. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18ima: Use audit_log_format() rather than audit_log_string()Stefan Berger1-2/+1
Remove the usage of audit_log_string() and replace it with audit_log_format(). Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Suggested-by: Steve Grubb <sgrubb@redhat.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18ima: Call audit_log_string() rather than logging it untrustedStefan Berger1-1/+1
The parameters passed to this logging function are all provided by a privileged user and therefore we can call audit_log_string() rather than audit_log_untrustedstring(). Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Suggested-by: Steve Grubb <sgrubb@redhat.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-16ima: based on policy warn about loading firmware (pre-allocated buffer)Mimi Zohar1-0/+8
Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. To resolve this problem, commit a098ecd2fa7d ("firmware: support loading into a pre-allocated buffer") introduced request_firmware_into_buf() API that allows drivers to request firmware be loaded directly into a pre-allocated buffer. Do devices using pre-allocated memory run the risk of the firmware being accessible to the device prior to the completion of IMA's signature verification any more than when using two buffers? (Refer to mailing list discussion[1]). Only on systems with an IOMMU can the access be prevented. As long as the signature verification completes prior to the DMA map is performed, the device can not access the buffer. This implies that the same buffer can not be re-used. Can we ensure the buffer has not been DMA mapped before using the pre-allocated buffer? [1] https://lkml.org/lkml/2018/7/10/56 Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16module: replace the existing LSM hook in init_moduleMimi Zohar1-13/+10
Both the init_module and finit_module syscalls call either directly or indirectly the security_kernel_read_file LSM hook. This patch replaces the direct call in init_module with a call to the new security_kernel_load_data hook and makes the corresponding changes in SELinux, LoadPin, and IMA. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Kees Cook <keescook@chromium.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16ima: add build time policyMimi Zohar2-3/+101
IMA by default does not measure, appraise or audit files, but can be enabled at runtime by specifying a builtin policy on the boot command line or by loading a custom policy. This patch defines a build time policy, which verifies kernel modules, firmware, kexec image, and/or the IMA policy signatures. This build time policy is automatically enabled at runtime and persists after loading a custom policy. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16ima: based on policy require signed firmware (sysfs fallback)Mimi Zohar1-1/+9
With an IMA policy requiring signed firmware, this patch prevents the sysfs fallback method of loading firmware. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Matthew Garrett <mjg59@google.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16ima: based on policy require signed kexec kernel imagesMimi Zohar3-0/+30
The original kexec_load syscall can not verify file signatures, nor can the kexec image be measured. Based on policy, deny the kexec_load syscall. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-12IMA: don't propagate opened through the entire thingAl Viro3-12/+12
just check ->f_mode in ima_appraise_measurement() Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-06-07Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-securityLinus Torvalds6-41/+71
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
2018-05-31IMA: use list_splice_tail_init_rcu() instead of its open coded variantPetko Manolov1-15/+2
Use list_splice_tail_init_rcu() to extend the existing custom IMA policy with additional IMA policy rules. Signed-off-by: Petko Manolov <petko.manolov@konsulko.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-31ima: use match_string() helperYisheng Xie1-7/+4
match_string() returns the index of an array for a matching string, which can be used intead of open coded variant. Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-22ima: fix updating the ima_appraise flagMimi Zohar1-9/+19
As IMA policy rules are added, a mask of the type of rule (eg. kernel modules, firmware, IMA policy) is updated. Unlike custom IMA policy rules, which replace the original builtin policy rules and update the mask, the builtin "secure_boot" policy rules were loaded, but did not update the mask. This patch refactors the code to load custom policies, defining a new function named ima_appraise_flag(). The new function is called either when loading the builtin "secure_boot" or custom policies. Fixes: 503ceaef8e2e ("ima: define a set of appraisal rules requiring file signatures") Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-22ima: based on policy verify firmware signatures (pre-allocated buffer)Mimi Zohar1-0/+1
Don't differentiate, for now, between kernel_read_file_id READING_FIRMWARE and READING_FIRMWARE_PREALLOC_BUFFER enumerations. Fixes: a098ecd firmware: support loading into a pre-allocated buffer (since 4.8) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: David Howells <dhowells@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Serge E. Hallyn <serge@hallyn.com> Cc: Stephen Boyd <stephen.boyd@linaro.org>
2018-05-22ima: define a new policy condition based on the filesystem nameMimi Zohar1-1/+24
If/when file data signatures are distributed with the file data, this patch will not be needed. In the current environment where only some files are signed, the ability to differentiate between file systems is needed. Some file systems consider the file system magic number internal to the file system. This patch defines a new IMA policy condition named "fsname", based on the superblock's file_system_type (sb->s_type) name. This allows policy rules to be expressed in terms of the filesystem name. The following sample rules require file signatures on rootfs files executed or mmap'ed. appraise func=BPRM_CHECK fsname=rootfs appraise_type=imasig appraise func=FILE_MMAP fsname=rootfs appraise_type=imasig Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Theodore Ts'o <tytso@mit.edu>
2018-05-17integrity: Add an integrity directory in securityfsMatthew Garrett1-1/+8
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>
2018-05-17ima: Remove unused variable ima_initializedPetr Vorel2-6/+2
Commit a756024 ("ima: added ima_policy_flag variable") replaced ima_initialized with ima_policy_flag, but didn't remove ima_initialized. This patch removes it. Signed-off-by: Petr Vorel <pvorel@suse.cz> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-17ima: Unify loggingPetr Vorel3-2/+9
Define pr_fmt everywhere. Signed-off-by: Petr Vorel <pvorel@suse.cz> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> (powerpc build error) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Changelog: Previous pr_fmt definition was too late and caused problems in powerpc allyesconfg build.
2018-05-17ima: Reflect correct permissions for policyPetr Vorel1-0/+2
Kernel configured as CONFIG_IMA_READ_POLICY=y && CONFIG_IMA_WRITE_POLICY=n keeps 0600 mode after loading policy. Remove write permission to state that policy file no longer be written. Signed-off-by: Petr Vorel <pvorel@suse.cz> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-05-14audit: use inline function to get audit contextRichard Guy Briggs1-1/+1
Recognizing that the audit context is an internal audit value, use an access function to retrieve the audit context pointer for the task rather than reaching directly into the task struct to get it. Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: merge fuzz in auditsc.c and selinuxfs.c, checkpatch.pl fixes] Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-03-25ima: Fallback to the builtin hash algorithmPetr Vorel2-0/+15
IMA requires having it's hash algorithm be compiled-in due to it's early use. The default IMA algorithm is protected by Kconfig to be compiled-in. The ima_hash kernel parameter allows to choose the hash algorithm. When the specified algorithm is not available or available as a module, IMA initialization fails, which leads to a kernel panic (mknodat syscall calls ima_post_path_mknod()). Therefore as fallback we force IMA to use the default builtin Kconfig hash algorithm. Fixed crash: $ grep CONFIG_CRYPTO_MD4 .config CONFIG_CRYPTO_MD4=m [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-4.12.14-2.3-default root=UUID=74ae8202-9ca7-4e39-813b-22287ec52f7a video=1024x768-16 plymouth.ignore-serial-consoles console=ttyS0 console=tty resume=/dev/disk/by-path/pci-0000:00:07.0-part3 splash=silent showopts ima_hash=md4 ... [ 1.545190] ima: Can not allocate md4 (reason: -2) ... [ 2.610120] BUG: unable to handle kernel NULL pointer dereference at (null) [ 2.611903] IP: ima_match_policy+0x23/0x390 [ 2.612967] PGD 0 P4D 0 [ 2.613080] Oops: 0000 [#1] SMP [ 2.613080] Modules linked in: autofs4 [ 2.613080] Supported: Yes [ 2.613080] CPU: 0 PID: 1 Comm: systemd Not tainted 4.12.14-2.3-default #1 [ 2.613080] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 [ 2.613080] task: ffff88003e2d0040 task.stack: ffffc90000190000 [ 2.613080] RIP: 0010:ima_match_policy+0x23/0x390 [ 2.613080] RSP: 0018:ffffc90000193e88 EFLAGS: 00010296 [ 2.613080] RAX: 0000000000000000 RBX: 000000000000000c RCX: 0000000000000004 [ 2.613080] RDX: 0000000000000010 RSI: 0000000000000001 RDI: ffff880037071728 [ 2.613080] RBP: 0000000000008000 R08: 0000000000000000 R09: 0000000000000000 [ 2.613080] R10: 0000000000000008 R11: 61c8864680b583eb R12: 00005580ff10086f [ 2.613080] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000008000 [ 2.613080] FS: 00007f5c1da08940(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000 [ 2.613080] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.613080] CR2: 0000000000000000 CR3: 0000000037002000 CR4: 00000000003406f0 [ 2.613080] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2.613080] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2.613080] Call Trace: [ 2.613080] ? shmem_mknod+0xbf/0xd0 [ 2.613080] ima_post_path_mknod+0x1c/0x40 [ 2.613080] SyS_mknod+0x210/0x220 [ 2.613080] entry_SYSCALL_64_fastpath+0x1a/0xa5 [ 2.613080] RIP: 0033:0x7f5c1bfde570 [ 2.613080] RSP: 002b:00007ffde1c90dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000085 [ 2.613080] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5c1bfde570 [ 2.613080] RDX: 0000000000000000 RSI: 0000000000008000 RDI: 00005580ff10086f [ 2.613080] RBP: 00007ffde1c91040 R08: 00005580ff10086f R09: 0000000000000000 [ 2.613080] R10: 0000000000104000 R11: 0000000000000246 R12: 00005580ffb99660 [ 2.613080] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 [ 2.613080] Code: 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 44 8d 14 09 41 55 41 54 55 53 44 89 d3 09 cb 48 83 ec 38 48 8b 05 c5 03 29 01 <4c> 8b 20 4c 39 e0 0f 84 d7 01 00 00 4c 89 44 24 08 89 54 24 20 [ 2.613080] RIP: ima_match_policy+0x23/0x390 RSP: ffffc90000193e88 [ 2.613080] CR2: 0000000000000000 [ 2.613080] ---[ end trace 9a9f0a8a73079f6a ]--- [ 2.673052] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 [ 2.673052] [ 2.675337] Kernel Offset: disabled [ 2.676405] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 Signed-off-by: Petr Vorel <pvorel@suse.cz> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-25ima: Add smackfs to the default appraise/measure listMartin Townsend1-0/+2
This is required to use SMACK and IMA/EVM together. Add it to the default nomeasure/noappraise list like other pseudo filesystems. Signed-off-by: Martin Townsend <mtownsend1973@gmail.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-25ima: Improvements in ima_appraise_measurement()Thiago Jung Bauermann1-13/+22
Replace nested ifs in the EVM xattr verification logic with a switch statement, making the code easier to understand. Also, add comments to the if statements in the out section and constify the cause variable. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com>
2018-03-25ima: Simplify ima_eventsig_init()Thiago Jung Bauermann1-8/+3
The "goto out" statement doesn't have any purpose since there's no cleanup to be done when returning early, so remove it. This also makes the rc variable unnecessary so remove it as well. Also, the xattr_len and fmt variables are redundant so remove them as well. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-25ima: drop vla in ima_audit_measurement()Tycho Andersen1-6/+10
In keeping with the directive to get rid of VLAs [1], let's drop the VLA from ima_audit_measurement(). We need to adjust the return type of ima_audit_measurement, because now this function can fail if an allocation fails. [1]: https://lkml.org/lkml/2018/3/7/621 v2: just use audit_log_format instead of doing a second allocation v3: ignore failures in ima_audit_measurement() Signed-off-by: Tycho Andersen <tycho@tycho.ws> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-25ima: Fix Kconfig to select TPM 2.0 CRB interfaceJiandi An1-0/+1
TPM_CRB driver provides TPM CRB 2.0 support. If it is built as a module, the TPM chip is registered after IMA init. tpm_pcr_read() in IMA fails and displays the following message even though eventually there is a TPM chip on the system. ima: No TPM chip found, activating TPM-bypass! (rc=-19) Fix IMA Kconfig to select TPM_CRB so TPM_CRB driver is built in the kernel and initializes before IMA. Signed-off-by: Jiandi An <anjiandi@codeaurora.org> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-23ima: fail signature verification based on policyMimi Zohar3-6/+13
This patch addresses the fuse privileged mounted filesystems in environments which are unwilling to accept the risk of trusting the signature verification and want to always fail safe, but are for example using a pre-built kernel. This patch defines a new builtin policy named "fail_securely", which can be specified on the boot command line as an argument to "ima_policy=". Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Dongsu Park <dongsu@kinvolk.io> Cc: Alban Crequy <alban@kinvolk.io> Acked-by: Serge Hallyn <serge@hallyn.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-03-23ima: clear IMA_HASHMimi Zohar1-1/+1
The IMA_APPRAISE and IMA_HASH policies overlap. Clear IMA_HASH properly. Fixes: da1b0029f527 ("ima: support new "hash" and "dont_hash" policy actions") Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-03-23ima: re-evaluate files on privileged mounted filesystemsMimi Zohar1-2/+11
This patch addresses the fuse privileged mounted filesystems in a "secure" environment, with a correctly enforced security policy, which is willing to assume the inherent risk of specific fuse filesystems that are well defined and properly implemented. As there is no way for the kernel to detect file changes, the kernel ignores the cached file integrity results and re-measures, re-appraises, and re-audits the file. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Dongsu Park <dongsu@kinvolk.io> Cc: Alban Crequy <alban@kinvolk.io> Acked-by: Serge Hallyn <serge@hallyn.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-03-23ima: fail file signature verification on non-init mounted filesystemsMimi Zohar1-1/+14
FUSE can be mounted by unprivileged users either today with fusermount installed with setuid, or soon with the upcoming patches to allow FUSE mounts in a non-init user namespace. This patch addresses the new unprivileged non-init mounted filesystems, which are untrusted, by failing the signature verification. This patch defines two new flags SB_I_IMA_UNVERIFIABLE_SIGNATURE and SB_I_UNTRUSTED_MOUNTER. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Dongsu Park <dongsu@kinvolk.io> Cc: Alban Crequy <alban@kinvolk.io> Acked-by: Serge Hallyn <serge@hallyn.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-03-23IMA: Support using new creds in appraisal policyMatthew Garrett5-27/+70
The existing BPRM_CHECK functionality in IMA validates against the credentials of the existing process, not any new credentials that the child process may transition to. Add an additional CREDS_CHECK target and refactor IMA to pass the appropriate creds structure. In ima_bprm_check(), check with both the existing process credentials and the credentials that will be committed when the new process is started. This will not change behaviour unless the system policy is extended to include CREDS_CHECK targets - BPRM_CHECK will continue to check the same credentials that it did previously. After this patch, an IMA policy rule along the lines of: measure func=CREDS_CHECK subj_type=unconfined_t will trigger if a process is executed and runs as unconfined_t, ignoring the context of the parent process. This is in contrast to: measure func=BPRM_CHECK subj_type=unconfined_t which will trigger if the process that calls exec() is already executing in unconfined_t, ignoring the context that the child process executes into. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Changelog: - initialize ima_creds_status
2018-02-01iversion: Rename make inode_cmp_iversion{+raw} to inode_eq_iversion{+raw}Goffredo Baroncelli1-1/+1
The function inode_cmp_iversion{+raw} is counter-intuitive, because it returns true when the counters are different and false when these are equal. Rename it to inode_eq_iversion{+raw}, which will returns true when the counters are equal and false otherwise. Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2018-01-31Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-securityLinus Torvalds3-3/+3
Pull tpm updates from James Morris: - reduce polling delays in tpm_tis - support retrieving TPM 2.0 Event Log through EFI before ExitBootServices - replace tpm-rng.c with a hwrng device managed by the driver for each TPM device - TPM resource manager synthesizes TPM_RC_COMMAND_CODE response instead of returning -EINVAL for unknown TPM commands. This makes user space more sound. - CLKRUN fixes: * Keep #CLKRUN disable through the entier TPM command/response flow * Check whether #CLKRUN is enabled before disabling and enabling it again because enabling it breaks PS/2 devices on a system where it is disabled * 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: tpm: remove unused variables tpm: remove unused data fields from I2C and OF device ID tables tpm: only attempt to disable the LPC CLKRUN if is already enabled tpm: follow coding style for variable declaration in tpm_tis_core_init() tpm: delete the TPM_TIS_CLK_ENABLE flag tpm: Update MAINTAINERS for Jason Gunthorpe tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd() tpm_tis: Move ilb_base_addr to tpm_tis_data tpm2-cmd: allow more attempts for selftest execution tpm: return a TPM_RC_COMMAND_CODE response if command is not implemented tpm: Move Linux RNG connection to hwrng tpm: use struct tpm_chip for tpm_chip_find_get() tpm: parse TPM event logs based on EFI table efi: call get_event_log before ExitBootServices tpm: add event log format version tpm: rename event log provider files tpm: move tpm_eventlog.h outside of drivers folder tpm: use tpm_msleep() value as max delay tpm: reduce tpm polling delay in tpm_tis_core tpm: move wait_for_tpm_stat() to respective driver files
2018-01-31Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-securityLinus Torvalds5-56/+127
Pull integrity updates from James Morris: "This contains a mixture of bug fixes, code cleanup, and new functionality. Of note is the integrity cache locking fix, file change detection, and support for a new EVM portable and immutable signature type. The re-introduction of the integrity cache lock (iint) fixes the problem of attempting to take the i_rwsem shared a second time, when it was previously taken exclusively. Defining atomic flags resolves the original iint/i_rwsem circular locking - accessing the file data vs. modifying the file metadata. Although it fixes the O_DIRECT problem as well, a subsequent patch is needed to remove the explicit O_DIRECT prevention. For performance reasons, detecting when a file has changed and needs to be re-measured, re-appraised, and/or re-audited, was limited to after the last writer has closed, and only if the file data has changed. Detecting file change is based on i_version. For filesystems that do not support i_version, remote filesystems, or userspace filesystems, the file was measured, appraised and/or audited once and never re-evaluated. Now local filesystems, which do not support i_version or are not mounted with the i_version option, assume the file has changed and are required to re-evaluate the file. This change does not address detecting file change on remote or userspace filesystems. Unlike file data signatures, which can be included and distributed in software packages (eg. rpm, deb), the existing EVM signature, which protects the file metadata, could not be included in software packages, as it includes file system specific information (eg. i_ino, possibly the UUID). This pull request defines a new EVM portable and immutable file metadata signature format, which can be included in software packages" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: ima/policy: fix parsing of fsuuid ima: Use i_version only when filesystem supports it integrity: remove unneeded initializations in integrity_iint_cache entries ima: log message to module appraisal error ima: pass filename to ima_rdwr_violation_check() ima: Fix line continuation format ima: support new "hash" and "dont_hash" policy actions ima: re-introduce own integrity cache lock EVM: Add support for portable signature format EVM: Allow userland to permit modification of EVM-protected metadata ima: relax requiring a file signature for new files with zero length
2018-01-29IMA: switch IMA over to new i_version APIJeff Layton2-2/+4
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2018-01-18ima/policy: fix parsing of fsuuidMike Rapoport1-1/+1
The switch to uuid_t invereted the logic of verfication that &entry->fsuuid is zero during parsing of "fsuuid=" rule. Instead of making sure the &entry->fsuuid field is not attempted to be overwritten, we bail out for perfectly correct rule. Fixes: 787d8c530af7 ("ima/policy: switch to use uuid_t") Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-01-08tpm: use struct tpm_chip for tpm_chip_find_get()Jarkko Sakkinen3-3/+3
Device number (the character device index) is not a stable identifier for a TPM chip. That is the reason why every call site passes TPM_ANY_NUM to tpm_chip_find_get(). This commit changes the API in a way that instead a struct tpm_chip instance is given and NULL means the default chip. In addition, this commit refines the documentation to be up to date with the implementation. Suggested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> (@chip_num -> @chip part) Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@ziepe.ca> Tested-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
2017-12-18ima: Use i_version only when filesystem supports itSascha Hauer1-1/+2
i_version is only supported by a filesystem when the SB_I_VERSION flag is set. This patch tests for the SB_I_VERSION flag before using i_version. If we can't use i_version to detect a file change then we must assume the file has changed in the last_writer path and remeasure it. On filesystems without i_version support IMA used to measure a file only once and didn't detect any changes to a file. With this patch IMA now works properly on these filesystems. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-12-18ima: log message to module appraisal errorBruno E. O. Meneguele1-1/+3
Simple but useful message log to the user in case of module appraise is forced and fails due to the lack of file descriptor, that might be caused by kmod calls to compressed modules. Signed-off-by: Bruno E. O. Meneguele <brdeoliv@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-12-18ima: pass filename to ima_rdwr_violation_check()Roberto Sassu1-3/+3
ima_rdwr_violation_check() retrieves the full path of a measured file by calling ima_d_path(). If process_measurement() calls this function, it reuses the pointer and passes it to the functions to measure/appraise/audit an accessed file. After commit bc15ed663e7e ("ima: fix ima_d_path() possible race with rename"), ima_d_path() first tries to retrieve the full path by calling d_absolute_path() and, if there is an error, copies the dentry name to the buffer passed as argument. However, ima_rdwr_violation_check() passes to ima_d_path() the pointer of a local variable. process_measurement() might be reusing the pointer to an area in the stack which may have been already overwritten after ima_rdwr_violation_check() returned. Correct this issue by passing to ima_rdwr_violation_check() the pointer of a buffer declared in process_measurement(). Fixes: bc15ed663e7e ("ima: fix ima_d_path() possible race with rename") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-12-18ima: Fix line continuation formatJoe Perches1-6/+5
Line continuations with excess spacing causes unexpected output. Based on commit 6f76b6fcaa60 ("CodingStyle: Document the exception of not splitting user-visible strings, for grepping") recommendation. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-12-18ima: support new "hash" and "dont_hash" policy actionsMimi Zohar4-10/+50
The builtin ima_appraise_tcb policy, which is specified on the boot command line, can be replaced with a custom policy, normally early in the boot process. Custom policies can be more restrictive in some ways, like requiring file signatures, but can be less restrictive in other ways, like not appraising mutable files. With a less restrictive policy in place, files in the builtin policy might not be hashed and labeled with a security.ima hash. On reboot, files which should be labeled in the ima_appraise_tcb are not labeled, possibly preventing the system from booting properly. To resolve this problem, this patch extends the existing IMA policy actions "measure", "dont_measure", "appraise", "dont_appraise", and "audit" with "hash" and "dont_hash". The new "hash" action will write the file hash as security.ima, but without requiring the file to be appraised as well. For example, the builtin ima_appraise_tcb policy includes the rule, "appraise fowner=0". Adding the "hash fowner=0" rule to a custom policy, will cause the needed file hashes to be calculated and written as security.ima xattrs. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
2017-12-13ima: Use i_version only when filesystem supports itSascha Hauer1-1/+2
i_version is only supported by a filesystem when the SB_I_VERSION flag is set. This patch tests for the SB_I_VERSION flag before using i_version. If we can't use i_version to detect a file change then we must assume the file has changed in the last_writer path and remeasure it. On filesystems without i_version support IMA used to measure a file only once and didn't detect any changes to a file. With this patch IMA now works properly on these filesystems. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-12-11ima: re-introduce own integrity cache lockDmitry Kasatkin2-35/+62
Before IMA appraisal was introduced, IMA was using own integrity cache lock along with i_mutex. process_measurement and ima_file_free took the iint->mutex first and then the i_mutex, while setxattr, chmod and chown took the locks in reverse order. To resolve the potential deadlock, i_mutex was moved to protect entire IMA functionality and the redundant iint->mutex was eliminated. Solution was based on the assumption that filesystem code does not take i_mutex further. But when file is opened with O_DIRECT flag, direct-io implementation takes i_mutex and produces deadlock. Furthermore, certain other filesystem operations, such as llseek, also take i_mutex. More recently some filesystems have replaced their filesystem specific lock with the global i_rwsem to read a file. As a result, when IMA attempts to calculate the file hash, reading the file attempts to take the i_rwsem again. To resolve O_DIRECT related deadlock problem, this patch re-introduces iint->mutex. But to eliminate the original chmod() related deadlock problem, this patch eliminates the requirement for chmod hooks to take the iint->mutex by introducing additional atomic iint->attr_flags to indicate calling of the hooks. The allowed locking order is to take the iint->mutex first and then the i_rwsem. Original flags were cleared in chmod(), setxattr() or removwxattr() hooks and tested when file was closed or opened again. New atomic flags are set or cleared in those hooks and tested to clear iint->flags on close or on open. Atomic flags are following: * IMA_CHANGE_ATTR - indicates that chATTR() was called (chmod, chown, chgrp) and file attributes have changed. On file open, it causes IMA to clear iint->flags to re-evaluate policy and perform IMA functions again. * IMA_CHANGE_XATTR - indicates that setxattr or removexattr was called and extended attributes have changed. On file open, it causes IMA to clear iint->flags IMA_DONE_MASK to re-appraise. * IMA_UPDATE_XATTR - indicates that security.ima needs to be updated. It is cleared if file policy changes and no update is needed. * IMA_DIGSIG - indicates that file security.ima has signature and file security.ima must not update to file has on file close. * IMA_MUST_MEASURE - indicates the file is in the measurement policy. Fixes: Commit 6552321831dc ("xfs: remove i_iolock and use i_rwsem in the VFS inode instead") Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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