kernel/linux.git/security/integrity, branch v6.6.40

ima: Avoid blocking in RCU read-side critical section

2024-07-11T10:49:18+00:00

commit 9a95c5bfbf02a0a7f5983280fe284a0ff0836c34 upstream. A panic happens in ima_match_policy: BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 PGD 42f873067 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 5 PID: 1286325 Comm: kubeletmonit.sh Kdump: loaded Tainted: P Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 RIP: 0010:ima_match_policy+0x84/0x450 Code: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39 7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea 44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f RSP: 0018:ff71570009e07a80 EFLAGS: 00010207 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200 RDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739 R10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970 R13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001 FS: 00007f5195b51740(0000) GS:ff3e278b12d40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ima_get_action+0x22/0x30 process_measurement+0xb0/0x830 ? page_add_file_rmap+0x15/0x170 ? alloc_set_pte+0x269/0x4c0 ? prep_new_page+0x81/0x140 ? simple_xattr_get+0x75/0xa0 ? selinux_file_open+0x9d/0xf0 ima_file_check+0x64/0x90 path_openat+0x571/0x1720 do_filp_open+0x9b/0x110 ? page_counter_try_charge+0x57/0xc0 ? files_cgroup_alloc_fd+0x38/0x60 ? __alloc_fd+0xd4/0x250 ? do_sys_open+0x1bd/0x250 do_sys_open+0x1bd/0x250 do_syscall_64+0x5d/0x1d0 entry_SYSCALL_64_after_hwframe+0x65/0xca Commit c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") introduced call to ima_lsm_copy_rule within a RCU read-side critical section which contains kmalloc with GFP_KERNEL. This implies a possible sleep and violates limitations of RCU read-side critical sections on non-PREEMPT systems. Sleeping within RCU read-side critical section might cause synchronize_rcu() returning early and break RCU protection, allowing a UAF to happen. The root cause of this issue could be described as follows: | Thread A | Thread B | | |ima_match_policy | | | rcu_read_lock | |ima_lsm_update_rule | | | synchronize_rcu | | | | kmalloc(GFP_KERNEL)| | | sleep | ==> synchronize_rcu returns early | kfree(entry) | | | | entry = entry->next| ==> UAF happens and entry now becomes NULL (or could be anything). | | entry->action | ==> Accessing entry might cause panic. To fix this issue, we are converting all kmalloc that is called within RCU read-side critical section to use GFP_ATOMIC. Fixes: c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") Cc: stable@vger.kernel.org Signed-off-by: GUO Zihua Acked-by: John Johansen Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler [PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case] Signed-off-by: Paul Moore Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: Fix use-after-free on a dentry's dname.name

2024-06-21T12:38:48+00:00

commit be84f32bb2c981ca670922e047cdde1488b233de upstream. ->d_name.name can change on rename and the earlier value can be freed; there are conditions sufficient to stabilize it (->d_lock on dentry, ->d_lock on its parent, ->i_rwsem exclusive on the parent's inode, rename_lock), but none of those are met at any of the sites. Take a stable snapshot of the name instead. Link: https://lore.kernel.org/all/20240202182732.GE2087318@ZenIV/ Signed-off-by: Al Viro Signed-off-by: Stefan Berger Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: detect changes to the backing overlay file

2023-11-28T17:20:03+00:00

commit b836c4d29f2744200b2af41e14bf50758dddc818 upstream. Commit 18b44bc5a672 ("ovl: Always reevaluate the file signature for IMA") forced signature re-evaulation on every file access. Instead of always re-evaluating the file's integrity, detect a change to the backing file, by comparing the cached file metadata with the backing file's metadata. Verifying just the i_version has not changed is insufficient. In addition save and compare the i_ino and s_dev as well. Reviewed-by: Amir Goldstein Tested-by: Eric Snowberg Tested-by: Raul E Rangel Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: annotate iint mutex to avoid lockdep false positive warnings

2023-11-28T17:20:03+00:00

commit e044374a8a0a99e46f4e6d6751d3042b6d9cc12e upstream. It is not clear that IMA should be nested at all, but as long is it measures files both on overlayfs and on underlying fs, we need to annotate the iint mutex to avoid lockdep false positives related to IMA + overlayfs, same as overlayfs annotates the inode mutex. Reported-and-tested-by: syzbot+b42fe626038981fb7bfa@syzkaller.appspotmail.com Signed-off-by: Amir Goldstein Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

integrity: powerpc: Do not select CA_MACHINE_KEYRING

2023-11-28T17:20:01+00:00

commit 3edc22655647378dea01900f7b04e017ff96bda9 upstream. No other platform needs CA_MACHINE_KEYRING, either. This is policy that should be decided by the administrator, not Kconfig dependencies. Cc: stable@vger.kernel.org # v6.6+ Fixes: d7d91c4743c4 ("integrity: PowerVM machine keyring enablement") Signed-off-by: Michal Suchanek Signed-off-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman

ima: rework CONFIG_IMA dependency block

2023-09-27T15:52:12+00:00

Changing the direct dependencies of IMA_BLACKLIST_KEYRING and IMA_LOAD_X509 caused them to no longer depend on IMA, but a a configuration without IMA results in link failures: arm-linux-gnueabi-ld: security/integrity/iint.o: in function `integrity_load_keys': iint.c:(.init.text+0xd8): undefined reference to `ima_load_x509' aarch64-linux-ld: security/integrity/digsig_asymmetric.o: in function `asymmetric_verify': digsig_asymmetric.c:(.text+0x104): undefined reference to `ima_blacklist_keyring' Adding explicit dependencies on IMA would fix this, but a more reliable way to do this is to enclose the entire Kconfig file in an 'if IMA' block. This also allows removing the existing direct dependencies. Fixes: be210c6d3597f ("ima: Finish deprecation of IMA_TRUSTED_KEYRING Kconfig") Signed-off-by: Arnd Bergmann Signed-off-by: Mimi Zohar

ima: Finish deprecation of IMA_TRUSTED_KEYRING Kconfig

2023-09-26T21:34:34+00:00

The removal of IMA_TRUSTED_KEYRING made IMA_LOAD_X509 and IMA_BLACKLIST_KEYRING unavailable because the latter two depend on the former. Since IMA_TRUSTED_KEYRING was deprecated in favor of INTEGRITY_TRUSTED_KEYRING use it as a dependency for the two Kconfigs affected by the deprecation. Fixes: 5087fd9e80e5 ("ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig") Signed-off-by: Oleksandr Tymoshenko Reviewed-by: Nayna Jain Signed-off-by: Mimi Zohar

Merge tag 'integrity-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

2023-08-30T16:16:56+00:00

Pull integrity subsystem updates from Mimi Zohar: - With commit 099f26f22f58 ("integrity: machine keyring CA configuration") certificates may be loaded onto the IMA keyring, directly or indirectly signed by keys on either the "builtin" or the "machine" keyrings. With the ability for the system/machine owner to sign the IMA policy itself without needing to recompile the kernel, update the IMA architecture specific policy rules to require the IMA policy itself be signed. [ As commit 099f26f22f58 was upstreamed in linux-6.4, updating the IMA architecture specific policy now to require signed IMA policies may break userspace expectations. ] - IMA only checked the file data hash was not on the system blacklist keyring for files with an appended signature (e.g. kernel modules, Power kernel image). Check all file data hashes regardless of how it was signed - Code cleanup, and a kernel-doc update * tag 'integrity-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: kexec_lock: Replace kexec_mutex() by kexec_lock() in two comments ima: require signed IMA policy when UEFI secure boot is enabled integrity: Always reference the blacklist keyring with appraisal ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig

Merge tag 'lsm-pr-20230829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

2023-08-30T16:07:09+00:00

Pull LSM updates from Paul Moore: - Add proper multi-LSM support for xattrs in the security_inode_init_security() hook Historically the LSM layer has only allowed a single LSM to add an xattr to an inode, with IMA/EVM measuring that and adding its own as well. As we work towards promoting IMA/EVM to a "proper LSM" instead of the special case that it is now, we need to better support the case of multiple LSMs each adding xattrs to an inode and after several attempts we now appear to have something that is working well. It is worth noting that in the process of making this change we uncovered a problem with Smack's SMACK64TRANSMUTE xattr which is also fixed in this pull request. - Additional LSM hook constification Two patches to constify parameters to security_capget() and security_binder_transfer_file(). While I generally don't make a special note of who submitted these patches, these were the work of an Outreachy intern, Khadija Kamran, and that makes me happy; hopefully it does the same for all of you reading this. - LSM hook comment header fixes One patch to add a missing hook comment header, one to fix a minor typo. - Remove an old, unused credential function declaration It wasn't clear to me who should pick this up, but it was trivial, obviously correct, and arguably the LSM layer has a vested interest in credentials so I merged it. Sadly I'm now noticing that despite my subject line cleanup I didn't cleanup the "unsued" misspelling, sigh * tag 'lsm-pr-20230829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: lsm: constify the 'file' parameter in security_binder_transfer_file() lsm: constify the 'target' parameter in security_capget() lsm: add comment block for security_sk_classify_flow LSM hook security: Fix ret values doc for security_inode_init_security() cred: remove unsued extern declaration change_create_files_as() evm: Support multiple LSMs providing an xattr evm: Align evm_inode_init_security() definition with LSM infrastructure smack: Set the SMACK64TRANSMUTE xattr in smack_inode_init_security() security: Allow all LSMs to provide xattrs for inode_init_security hook lsm: fix typo in security_file_lock() comment header

Merge tag 'tpmdd-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd

2023-08-29T15:05:18+00:00

Pull tpm updates from Jarkko Sakkinen: - Restrict linking of keys to .ima and .evm keyrings based on digitalSignature attribute in the certificate - PowerVM: load machine owner keys into the .machine [1] keyring - PowerVM: load module signing keys into the secondary trusted keyring (keys blessed by the vendor) - tpm_tis_spi: half-duplex transfer mode - tpm_tis: retry corrupted transfers - Apply revocation list (.mokx) to an all system keyrings (e.g. .machine keyring) Link: https://blogs.oracle.com/linux/post/the-machine-keyring [1] * tag 'tpmdd-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd: certs: Reference revocation list for all keyrings tpm/tpm_tis_synquacer: Use module_platform_driver macro to simplify the code tpm: remove redundant variable len tpm_tis: Resend command to recover from data transfer errors tpm_tis: Use responseRetry to recover from data transfer errors tpm_tis: Move CRC check to generic send routine tpm_tis_spi: Add hardware wait polling KEYS: Replace all non-returning strlcpy with strscpy integrity: PowerVM support for loading third party code signing keys integrity: PowerVM machine keyring enablement integrity: check whether imputed trust is enabled integrity: remove global variable from machine_keyring.c integrity: ignore keys failing CA restrictions on non-UEFI platform integrity: PowerVM support for loading CA keys on machine keyring integrity: Enforce digitalSignature usage in the ima and evm keyrings KEYS: DigitalSignature link restriction tpm_tis: Revert "tpm_tis: Disable interrupts on ThinkPad T490s"