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2022-07-13Documentation: siphash: Fix typo in the name of offsetofend macroDov Murik1-1/+1
The siphash documentation misspelled "offsetendof" instead of "offsetofend". Fixes: 2c956a60778cbb ("siphash: add cryptographically secure PRF") Signed-off-by: Dov Murik <dovmurik@linux.ibm.com> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Link: https://lore.kernel.org/r/20220712104455.1408150-1-dovmurik@linux.ibm.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07Documentation: KVM: update amd-memory-encryption.rst referencesMauro Carvalho Chehab1-1/+1
Changeset daec8d408308 ("Documentation: KVM: add separate directories for architecture-specific documentation") renamed: Documentation/virt/kvm/amd-memory-encryption.rst to: Documentation/virt/kvm/x86/amd-memory-encryption.rst. Update the cross-references accordingly. Fixes: daec8d408308 ("Documentation: KVM: add separate directories for architecture-specific documentation") Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org> Link: https://lore.kernel.org/r/fd80db889e34aae87a4ca88cad94f650723668f4.1656234456.git.mchehab@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07Documentation: update watch_queue.rst referencesMauro Carvalho Chehab1-1/+1
Changeset f5461124d59b ("Documentation: move watch_queue to core-api") renamed: Documentation/watch_queue.rst to: Documentation/core-api/watch_queue.rst. Update the cross-references accordingly. Fixes: f5461124d59b ("Documentation: move watch_queue to core-api") Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org> Link: https://lore.kernel.org/r/1c220de9c58f35e815a3df9458ac2bea323c8bfb.1656234456.git.mchehab@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-05-24Merge tag 'integrity-v5.19' of ↵Linus Torvalds1-4/+7
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull IMA updates from Mimi Zohar: "New is IMA support for including fs-verity file digests and signatures in the IMA measurement list as well as verifying the fs-verity file digest based signatures, both based on policy. In addition, are two bug fixes: - avoid reading UEFI variables, which cause a page fault, on Apple Macs with T2 chips. - remove the original "ima" template Kconfig option to address a boot command line ordering issue. The rest is a mixture of code/documentation cleanup" * tag 'integrity-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: integrity: Fix sparse warnings in keyring_handler evm: Clean up some variables evm: Return INTEGRITY_PASS for enum integrity_status value '0' efi: Do not import certificates from UEFI Secure Boot for T2 Macs fsverity: update the documentation ima: support fs-verity file digest based version 3 signatures ima: permit fsverity's file digests in the IMA measurement list ima: define a new template field named 'd-ngv2' and templates fs-verity: define a function to return the integrity protected file digest ima: use IMA default hash algorithm for integrity violations ima: fix 'd-ng' comments and documentation ima: remove the IMA_TEMPLATE Kconfig option ima: remove redundant initialization of pointer 'file'.
2022-05-24Merge tag 'tpmdd-next-v5.19-rc1' of ↵Linus Torvalds1-9/+51
git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd Pull tpm updates from Jarkko Sakkinen: - Tightened validation of key hashes for SYSTEM_BLACKLIST_HASH_LIST. An invalid hash format causes a compilation error. Previously, they got included to the kernel binary but were silently ignored at run-time. - Allow root user to append new hashes to the blacklist keyring. - Trusted keys backed with Cryptographic Acceleration and Assurance Module (CAAM), which part of some of the new NXP's SoC's. Now there is total three hardware backends for trusted keys: TPM, ARM TEE and CAAM. - A scattered set of fixes and small improvements for the TPM driver. * tag 'tpmdd-next-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd: MAINTAINERS: add KEYS-TRUSTED-CAAM doc: trusted-encrypted: describe new CAAM trust source KEYS: trusted: Introduce support for NXP CAAM-based trusted keys crypto: caam - add in-kernel interface for blob generator crypto: caam - determine whether CAAM supports blob encap/decap KEYS: trusted: allow use of kernel RNG for key material KEYS: trusted: allow use of TEE as backend without TCG_TPM support tpm: Add field upgrade mode support for Infineon TPM2 modules tpm: Fix buffer access in tpm2_get_tpm_pt() char: tpm: cr50_i2c: Suppress duplicated error message in .remove() tpm: cr50: Add new device/vendor ID 0x504a6666 tpm: Remove read16/read32/write32 calls from tpm_tis_phy_ops tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe() tpm/tpm_ftpm_tee: Return true/false (not 1/0) from bool functions certs: Explain the rationale to call panic() certs: Allow root user to append signed hashes to the blacklist keyring certs: Check that builtin blacklist hashes are valid certs: Make blacklist_vet_description() more strict certs: Factor out the blacklist hash creation tools/certs: Add print-cert-tbs-hash.sh
2022-05-24Merge tag 'landlock-5.19-rc1' of ↵Linus Torvalds1-1/+16
git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux Pull Landlock updates from Mickaël Salaün: - improve the path_rename LSM hook implementations for RENAME_EXCHANGE; - fix a too-restrictive filesystem control for a rare corner case; - set the nested sandbox limitation to 16 layers; - add a new LANDLOCK_ACCESS_FS_REFER access right to properly handle file reparenting (i.e. full rename and link support); - add new tests and documentation; - format code with clang-format to make it easier to maintain and contribute. * tag 'landlock-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: (30 commits) landlock: Explain how to support Landlock landlock: Add design choices documentation for filesystem access rights landlock: Document good practices about filesystem policies landlock: Document LANDLOCK_ACCESS_FS_REFER and ABI versioning samples/landlock: Add support for file reparenting selftests/landlock: Add 11 new test suites dedicated to file reparenting landlock: Add support for file reparenting with LANDLOCK_ACCESS_FS_REFER LSM: Remove double path_rename hook calls for RENAME_EXCHANGE landlock: Move filesystem helpers and add a new one landlock: Fix same-layer rule unions landlock: Create find_rule() from unmask_layers() landlock: Reduce the maximum number of layers to 16 landlock: Define access_mask_t to enforce a consistent access mask size selftests/landlock: Test landlock_create_ruleset(2) argument check ordering landlock: Change landlock_restrict_self(2) check ordering landlock: Change landlock_add_rule(2) argument check ordering selftests/landlock: Add tests for O_PATH selftests/landlock: Fully test file rename with "remove" access selftests/landlock: Extend access right tests to directories selftests/landlock: Add tests for unknown access rights ...
2022-05-23Merge tag 'efi-next-for-v5.19' of ↵Linus Torvalds3-0/+113
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: - Allow runtime services to be re-enabled at boot on RT kernels. - Provide access to secrets injected into the boot image by CoCo hypervisors (COnfidential COmputing) - Use DXE services on x86 to make the boot image executable after relocation, if needed. - Prefer mirrored memory for randomized allocations. - Only randomize the placement of the kernel image on arm64 if the loader has not already done so. - Add support for obtaining the boot hartid from EFI on RISC-V. * tag 'efi-next-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: riscv/efi_stub: Add support for RISCV_EFI_BOOT_PROTOCOL efi: stub: prefer mirrored memory for randomized allocations efi/arm64: libstub: run image in place if randomized by the loader efi: libstub: pass image handle to handle_kernel_image() efi: x86: Set the NX-compatibility flag in the PE header efi: libstub: ensure allocated memory to be executable efi: libstub: declare DXE services table efi: Add missing prototype for efi_capsule_setup_info docs: security: Add secrets/coco documentation efi: Register efi_secret platform device if EFI secret area is declared virt: Add efi_secret module to expose confidential computing secrets efi: Save location of EFI confidential computing area efi: Allow to enable EFI runtime services by default on RT
2022-05-23doc: trusted-encrypted: describe new CAAM trust sourceAhmad Fatoum1-1/+39
Update documentation for trusted key use with the Cryptographic Acceleration and Assurance Module (CAAM), an IP on NXP SoCs. Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-05-23KEYS: trusted: allow use of kernel RNG for key materialAhmad Fatoum1-8/+12
The two existing trusted key sources don't make use of the kernel RNG, but instead let the hardware doing the sealing/unsealing also generate the random key material. However, both users and future backends may want to place less trust into the quality of the trust source's random number generator and instead reuse the kernel entropy pool, which can be seeded from multiple entropy sources. Make this possible by adding a new trusted.rng parameter, that will force use of the kernel RNG. In its absence, it's up to the trust source to decide, which random numbers to use, maintaining the existing behavior. Suggested-by: Jarkko Sakkinen <jarkko@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Acked-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: David Gstir <david@sigma-star.at> Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Pankaj Gupta <pankaj.gupta@nxp.com> Tested-by: Michael Walle <michael@walle.cc> # on ls1028a (non-E and E) Tested-by: John Ernberg <john.ernberg@actia.se> # iMX8QXP Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-05-23landlock: Add design choices documentation for filesystem access rightsMickaël Salaün1-1/+16
Summarize the rationale of filesystem access rights according to the file type. Update the document date. Reviewed-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mickaël Salaün <mic@digikod.net> Link: https://lore.kernel.org/r/20220506161102.525323-13-mic@digikod.net
2022-05-06ima: support fs-verity file digest based version 3 signaturesMimi Zohar1-2/+2
IMA may verify a file's integrity against a "good" value stored in the 'security.ima' xattr or as an appended signature, based on policy. When the "good value" is stored in the xattr, the xattr may contain a file hash or signature. In either case, the "good" value is preceded by a header. The first byte of the xattr header indicates the type of data - hash, signature - stored in the xattr. To support storing fs-verity signatures in the 'security.ima' xattr requires further differentiating the fs-verity signature from the existing IMA signature. In addition the signatures stored in 'security.ima' xattr, need to be disambiguated. Instead of directly signing the fs-verity digest, a new signature format version 3 is defined as the hash of the ima_file_id structure, which identifies the type of signature and the digest. The IMA policy defines "which" files are to be measured, verified, and/or audited. For those files being verified, the policy rules indicate "how" the file should be verified. For example to require a file be signed, the appraise policy rule must include the 'appraise_type' option. appraise_type:= [imasig] | [imasig|modsig] | [sigv3] where 'imasig' is the original or signature format v2 (default), where 'modsig' is an appended signature, where 'sigv3' is the signature format v3. The policy rule must also indicate the type of digest, if not the IMA default, by first specifying the digest type: digest_type:= [verity] The following policy rule requires fsverity signatures. The rule may be constrained, for example based on a fsuuid or LSM label. appraise func=BPRM_CHECK digest_type=verity appraise_type=sigv3 Acked-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-05ima: permit fsverity's file digests in the IMA measurement listMimi Zohar1-1/+1
Permit fsverity's file digest (a hash of struct fsverity_descriptor) to be included in the IMA measurement list, based on the new measurement policy rule 'digest_type=verity' option. To differentiate between a regular IMA file hash from an fsverity's file digest, use the new d-ngv2 format field included in the ima-ngv2 template. The following policy rule requires fsverity file digests and specifies the new 'ima-ngv2' template, which contains the new 'd-ngv2' field. The policy rule may be constrained, for example based on a fsuuid or LSM label. measure func=FILE_CHECK digest_type=verity template=ima-ngv2 Acked-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-05ima: define a new template field named 'd-ngv2' and templatesMimi Zohar1-0/+4
In preparation to differentiate between unsigned regular IMA file hashes and fs-verity's file digests in the IMA measurement list, define a new template field named 'd-ngv2'. Also define two new templates named 'ima-ngv2' and 'ima-sigv2', which include the new 'd-ngv2' field. Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-01ima: fix 'd-ng' comments and documentationMimi Zohar1-2/+1
Initially the 'd-ng' template field did not prefix the digest with either "md5" or "sha1" hash algorithms. Prior to being upstreamed this changed, but the comments and documentation were not updated. Fix the comments and documentation. Fixes: 4d7aeee73f53 ("ima: define new template ima-ng and template fields d-ng and n-ng") Reported-by: Eric Biggers <ebiggers@kernel.org> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-04-25Documentation: siphash: disambiguate HalfSipHash algorithm from hsiphash ↵Eric Biggers1-12/+22
functions Fix the documentation for the hsiphash functions to avoid conflating the HalfSipHash algorithm with the hsiphash functions, since these functions actually implement either HalfSipHash or SipHash, and random.c now uses HalfSipHash (in a very special way) without the hsiphash functions. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-04-25Documentation: siphash: enclose HalfSipHash usage example in the literal blockBagas Sanjaya1-3/+3
Render usage example of HalfSipHash function as code block by using literal block syntax. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Eric Biggers <ebiggers@google.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-04-25Documentation: siphash: convert danger note to warning for HalfSipHashBagas Sanjaya1-6/+6
Render danger paragraph into warning block for emphasization. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Eric Biggers <ebiggers@google.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-04-13docs: security: Add secrets/coco documentationDov Murik3-0/+113
Add documentation for the efi_secret module which allows access to Confidential Computing injected secrets. Signed-off-by: Dov Murik <dovmurik@linux.ibm.com> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Link: https://lore.kernel.org/r/20220412212127.154182-5-dovmurik@linux.ibm.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-03-22Merge tag 'selinux-pr-20220321' of ↵Linus Torvalds1-14/+12
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "We've got a number of SELinux patches queued up, the highlights are: - Fixup the security_fs_context_parse_param() LSM hook so it executes all of the LSM hook implementations unless a serious error occurs. We also correct the SELinux hook implementation so that it returns zero on success. - In addition to a few SELinux mount option parsing fixes, we simplified the parsing by moving it earlier in the process. The logic was that it was unlikely an admin/user would use the new mount API and not have the policy loaded before passing the SELinux options. - Properly fixed the LSM/SELinux/SCTP hooks with the addition of the security_sctp_assoc_established() hook. This work was done in conjunction with the netdev folks and should complete the move of the SCTP labeling from the endpoints to the associations. - Fixed a variety of sparse warnings caused by changes in the "__rcu" markings of some core kernel structures. - Ensure we access the superblock's LSM security blob using the stacking-safe accessors. - Added the ability for the kernel to always allow FIOCLEX and FIONCLEX if the "ioctl_skip_cloexec" policy capability is specified. - Various constifications improvements, type casting improvements, additional return value checks, and dead code/parameter removal. - Documentation fixes" * tag 'selinux-pr-20220321' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: (23 commits) selinux: shorten the policy capability enum names docs: fix 'make htmldocs' warning in SCTP.rst selinux: allow FIOCLEX and FIONCLEX with policy capability selinux: use correct type for context length selinux: drop return statement at end of void functions security: implement sctp_assoc_established hook in selinux security: add sctp_assoc_established hook selinux: parse contexts for mount options early selinux: various sparse fixes selinux: try to use preparsed sid before calling parse_sid() selinux: Fix selinux_sb_mnt_opts_compat() LSM: general protection fault in legacy_parse_param selinux: fix a type cast problem in cred_init_security() selinux: drop unused macro selinux: simplify cred_init_security selinux: do not discard const qualifier in cast selinux: drop unused parameter of avtab_insert_node selinux: drop cast to same type selinux: enclose macro arguments in parenthesis selinux: declare name parameter of hash_eval const ...
2022-02-28docs: fix 'make htmldocs' warning in SCTP.rstWan Jiabing1-2/+2
Fix following 'make htmldocs' warnings: ./Documentation/security/SCTP.rst:123: WARNING: Title underline too short. security_sctp_assoc_established() ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./Documentation/security/SCTP.rst:123: WARNING: Title underline too short. security_sctp_assoc_established() ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./Documentation/security/SCTP.rst:273: WARNING: Title underline too short. security_sctp_assoc_established() ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./Documentation/security/SCTP.rst:273: WARNING: Title underline too short. security_sctp_assoc_established() ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fixes: 5e50f5d4ff31 ("security: add sctp_assoc_established hook") Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-02-22KEYS: encrypted: Instantiate key with user-provided decrypted dataYael Tzur1-6/+19
For availability and performance reasons master keys often need to be released outside of a Key Management Service (KMS) to clients. It would be beneficial to provide a mechanism where the wrapping/unwrapping of data encryption keys (DEKs) is not dependent on a remote call at runtime yet security is not (or only minimally) compromised. Master keys could be securely stored in the Kernel and be used to wrap/unwrap keys from Userspace. The encrypted.c class supports instantiation of encrypted keys with either an already-encrypted key material, or by generating new key material based on random numbers. This patch defines a new datablob format: [<format>] <master-key name> <decrypted data length> <decrypted data> that allows to inject and encrypt user-provided decrypted data. The decrypted data must be hex-ascii encoded. Signed-off-by: Yael Tzur <yaelt@google.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-02-15security: add sctp_assoc_established hookOndrej Mosnacek1-12/+10
security_sctp_assoc_established() is added to replace security_inet_conn_established() called in sctp_sf_do_5_1E_ca(), so that asoc can be accessed in security subsystem and save the peer secid to asoc->peer_secid. Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Based-on-patch-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-12-11docs: update self-protection __ro_after_init statusShuah Khan1-2/+1
__ro_after_init is no longer new and under development. Update the document to reflect the correct status. Signed-off-by: Shuah Khan <skhan@linuxfoundation.org> Link: https://lore.kernel.org/r/20211208164051.8783-1-skhan@linuxfoundation.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-12net,lsm,selinux: revert the security_sctp_assoc_established() hookPaul Moore1-10/+12
This patch reverts two prior patches, e7310c94024c ("security: implement sctp_assoc_established hook in selinux") and 7c2ef0240e6a ("security: add sctp_assoc_established hook"), which create the security_sctp_assoc_established() LSM hook and provide a SELinux implementation. Unfortunately these two patches were merged without proper review (the Reviewed-by and Tested-by tags from Richard Haines were for previous revisions of these patches that were significantly different) and there are outstanding objections from the SELinux maintainers regarding these patches. Work is currently ongoing to correct the problems identified in the reverted patches, as well as others that have come up during review, but it is unclear at this point in time when that work will be ready for inclusion in the mainline kernel. In the interest of not keeping objectionable code in the kernel for multiple weeks, and potentially a kernel release, we are reverting the two problematic patches. Signed-off-by: Paul Moore <paul@paul-moore.com>
2021-11-03security: add sctp_assoc_established hookXin Long1-12/+10
security_sctp_assoc_established() is added to replace security_inet_conn_established() called in sctp_sf_do_5_1E_ca(), so that asoc can be accessed in security subsystem and save the peer secid to asoc->peer_secid. v1->v2: - fix the return value of security_sctp_assoc_established() in security.h, found by kernel test robot and Ondrej. Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Reviewed-by: Richard Haines <richard_c_haines@btinternet.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-03security: call security_sctp_assoc_request in sctp_sf_do_5_1D_ceXin Long1-6/+9
The asoc created when receives the INIT chunk is a temporary one, it will be deleted after INIT_ACK chunk is replied. So for the real asoc created in sctp_sf_do_5_1D_ce() when the COOKIE_ECHO chunk is received, security_sctp_assoc_request() should also be called. v1->v2: - fix some typo and grammar errors, noticed by Ondrej. Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Reviewed-by: Richard Haines <richard_c_haines@btinternet.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-03security: pass asoc to sctp_assoc_request and sctp_sk_cloneXin Long1-14/+14
This patch is to move secid and peer_secid from endpoint to association, and pass asoc to sctp_assoc_request and sctp_sk_clone instead of ep. As ep is the local endpoint and asoc represents a connection, and in SCTP one sk/ep could have multiple asoc/connection, saving secid/peer_secid for new asoc will overwrite the old asoc's. Note that since asoc can be passed as NULL, security_sctp_assoc_request() is moved to the place right after the new_asoc is created in sctp_sf_do_5_1B_init() and sctp_sf_do_unexpected_init(). v1->v2: - fix the description of selinux_netlbl_skbuff_setsid(), as Jakub noticed. - fix the annotation in selinux_sctp_assoc_request(), as Richard Noticed. Fixes: 72e89f50084c ("security: Add support for SCTP security hooks") Reported-by: Prashanth Prahlad <pprahlad@redhat.com> Reviewed-by: Richard Haines <richard_c_haines@btinternet.com> Tested-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29Merge tag 'docs-5.14' of git://git.lwn.net/linuxLinus Torvalds1-1/+2
Pull documentation updates from Jonathan Corbet: "This was a reasonably active cycle for documentation; this includes: - Some kernel-doc cleanups. That script is still regex onslaught from hell, but it has gotten a little better. - Improvements to the checkpatch docs, which are also used by the tool itself. - A major update to the pathname lookup documentation. - Elimination of :doc: markup, since our automarkup magic can create references from filenames without all the extra noise. - The flurry of Chinese translation activity continues. Plus, of course, the usual collection of updates, typo fixes, and warning fixes" * tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits) docs: path-lookup: use bare function() rather than literals docs: path-lookup: update symlink description docs: path-lookup: update get_link() ->follow_link description docs: path-lookup: update WALK_GET, WALK_PUT desc docs: path-lookup: no get_link() docs: path-lookup: update i_op->put_link and cookie description docs: path-lookup: i_op->follow_link replaced with i_op->get_link docs: path-lookup: Add macro name to symlink limit description docs: path-lookup: remove filename_mountpoint docs: path-lookup: update do_last() part docs: path-lookup: update path_mountpoint() part docs: path-lookup: update path_to_nameidata() part docs: path-lookup: update follow_managed() part docs: Makefile: Use CONFIG_SHELL not SHELL docs: Take a little noise out of the build process docs: x86: avoid using ReST :doc:`foo` markup docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup ...
2021-06-17docs: security: landlock.rst: avoid using ReST :doc:`foo` markupMauro Carvalho Chehab1-1/+2
The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/9174021ef2c87f395a4cc0895a4b2f7fd97db626.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-08doc: Fix warning in Documentation/security/IMA-templates.rstRoberto Sassu1-1/+1
This patch fixes the warning: Documentation/security/IMA-templates.rst:81: WARNING: Inline substitution_reference start-string without end-string. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-06-03ima: Define new template evm-sigRoberto Sassu1-0/+1
With the recent introduction of the evmsig template field, remote verifiers can obtain the EVM portable signature instead of the IMA signature, to verify file metadata. After introducing the new fields to include file metadata in the measurement list, this patch finally defines the evm-sig template, whose format is: d-ng|n-ng|evmsig|xattrnames|xattrlengths|xattrvalues|iuid|igid|imode xattrnames, xattrlengths and xattrvalues are populated only from defined EVM protected xattrs, i.e. the ones that EVM considers to verify the portable signature. xattrnames and xattrlengths are populated only if the xattr is present. xattrnames and xattrlengths are not necessary for verifying the EVM portable signature, but they are included for completeness of information, if a remote verifier wants to infer more from file metadata. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-06-03ima: Define new template fields xattrnames, xattrlengths and xattrvaluesRoberto Sassu1-0/+4
This patch defines the new template fields xattrnames, xattrlengths and xattrvalues, which contain respectively a list of xattr names (strings, separated by |), lengths (u32, hex) and values (hex). If an xattr is not present, the name and length are not displayed in the measurement list. Reported-by: kernel test robot <lkp@intel.com> (Missing prototype def) Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-06-01ima: Define new template field imodeRoberto Sassu1-0/+1
This patch defines the new template field imode, which includes the inode mode. It can be used by a remote verifier to verify the EVM portable signature, if it was included with the template fields sig or evmsig. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-06-01ima: Define new template fields iuid and igidRoberto Sassu1-0/+2
This patch defines the new template fields iuid and igid, which include respectively the inode UID and GID. For idmapped mounts, still the original UID and GID are provided. These fields can be used to verify the EVM portable signature, if it was included with the template fields sig or evmsig. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-06-01ima: Introduce template field evmsig and write to field sig as fallbackRoberto Sassu1-1/+3
With the patch to accept EVM portable signatures when the appraise_type=imasig requirement is specified in the policy, appraisal can be successfully done even if the file does not have an IMA signature. However, remote attestation would not see that a different signature type was used, as only IMA signatures can be included in the measurement list. This patch solves the issue by introducing the new template field 'evmsig' to show EVM portable signatures and by including its value in the existing field 'sig' if the IMA signature is not found. Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-05-11Documentation: drop optional BOMsRandy Dunlap1-1/+1
A few of the Documentation .rst files begin with a Unicode byte order mark (BOM). The BOM may signify endianess for 16-bit or 32-bit encodings or indicate that the text stream is indeed Unicode. We don't need it for either of those uses. It may also interfere with (confuse) some software. Since we don't need it and its use is optional, just delete the uses of it in Documentation/. https://en.wikipedia.org/wiki/Byte_order_mark Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Link: https://lore.kernel.org/r/20210506231907.14359-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-02Merge tag 'landlock_v34' of ↵Linus Torvalds2-0/+86
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull Landlock LSM from James Morris: "Add Landlock, a new LSM from Mickaël Salaün. Briefly, Landlock provides for unprivileged application sandboxing. From Mickaël's cover letter: "The goal of Landlock is to enable to restrict ambient rights (e.g. global filesystem access) for a set of processes. Because Landlock is a stackable LSM [1], it makes possible to create safe security sandboxes as new security layers in addition to the existing system-wide access-controls. This kind of sandbox is expected to help mitigate the security impact of bugs or unexpected/malicious behaviors in user-space applications. Landlock empowers any process, including unprivileged ones, to securely restrict themselves. Landlock is inspired by seccomp-bpf but instead of filtering syscalls and their raw arguments, a Landlock rule can restrict the use of kernel objects like file hierarchies, according to the kernel semantic. Landlock also takes inspiration from other OS sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD Pledge/Unveil. In this current form, Landlock misses some access-control features. This enables to minimize this patch series and ease review. This series still addresses multiple use cases, especially with the combined use of seccomp-bpf: applications with built-in sandboxing, init systems, security sandbox tools and security-oriented APIs [2]" The cover letter and v34 posting is here: https://lore.kernel.org/linux-security-module/20210422154123.13086-1-mic@digikod.net/ See also: https://landlock.io/ This code has had extensive design discussion and review over several years" Link: https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@schaufler-ca.com/ [1] Link: https://lore.kernel.org/lkml/f646e1c7-33cf-333f-070c-0a40ad0468cd@digikod.net/ [2] * tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: landlock: Enable user space to infer supported features landlock: Add user and kernel documentation samples/landlock: Add a sandbox manager example selftests/landlock: Add user space tests landlock: Add syscall implementations arch: Wire up Landlock syscalls fs,security: Add sb_delete hook landlock: Support filesystem access-control LSM: Infrastructure management of the superblock landlock: Add ptrace restrictions landlock: Set up the security framework and manage credentials landlock: Add ruleset and domain management landlock: Add object management
2021-04-22landlock: Add user and kernel documentationMickaël Salaün2-0/+86
Add a first document describing userspace API: how to define and enforce a Landlock security policy. This is explained with a simple example. The Landlock system calls are described with their expected behavior and current limitations. Another document is dedicated to kernel developers, describing guiding principles and some important kernel structures. This documentation can be built with the Sphinx framework. Cc: James Morris <jmorris@namei.org> Cc: Jann Horn <jannh@google.com> Cc: Serge E. Hallyn <serge@hallyn.com> Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com> Reviewed-by: Vincent Dagonneau <vincent.dagonneau@ssi.gouv.fr> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210422154123.13086-13-mic@digikod.net Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2021-04-14doc: trusted-encrypted: updates with TEE as a new trust sourceSumit Garg1-33/+138
Update documentation for Trusted and Encrypted Keys with TEE as a new trust source. Following is brief description of updates: - Add a section to demonstrate a list of supported devices along with their security properties/guarantees. - Add a key generation section. - Updates for usage section including differences specific to a trust source. Co-developed-by: Elaine Palmer <erpalmer@us.ibm.com> Signed-off-by: Elaine Palmer <erpalmer@us.ibm.com> Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2021-04-14security: keys: trusted: use ASN.1 TPM2 key format for the blobsJames Bottomley1-0/+58
Modify the TPM2 key format blob output to export and import in the ASN.1 form for TPM2 sealed object keys. For compatibility with prior trusted keys, the importer will also accept two TPM2B quantities representing the public and private parts of the key. However, the export via keyctl pipe will only output the ASN.1 format. The benefit of the ASN.1 format is that it's a standard and thus the exported key can be used by userspace tools (openssl_tpm2_engine, openconnect and tpm2-tss-engine). The format includes policy specifications, thus it gets us out of having to construct policy handles in userspace and the format includes the parent meaning you don't have to keep passing it in each time. This patch only implements basic handling for the ASN.1 format, so keys with passwords but no policy. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2021-02-24Merge tag 'keys-misc-20210126' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull keyring updates from David Howells: "Here's a set of minor keyrings fixes/cleanups that I've collected from various people for the upcoming merge window. A couple of them might, in theory, be visible to userspace: - Make blacklist_vet_description() reject uppercase letters as they don't match the all-lowercase hex string generated for a blacklist search. This may want reconsideration in the future, but, currently, you can't add to the blacklist keyring from userspace and the only source of blacklist keys generates lowercase descriptions. - Fix blacklist_init() to use a new KEY_ALLOC_* flag to indicate that it wants KEY_FLAG_KEEP to be set rather than passing KEY_FLAG_KEEP into keyring_alloc() as KEY_FLAG_KEEP isn't a valid alloc flag. This isn't currently a problem as the blacklist keyring isn't currently writable by userspace. The rest of the patches are cleanups and I don't think they should have any visible effect" * tag 'keys-misc-20210126' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: watch_queue: rectify kernel-doc for init_watch() certs: Replace K{U,G}IDT_INIT() with GLOBAL_ROOT_{U,G}ID certs: Fix blacklist flag type confusion PKCS#7: Fix missing include certs: Fix blacklisted hexadecimal hash string check certs/blacklist: fix kernel doc interface issue crypto: public_key: Remove redundant header file from public_key.h keys: remove trailing semicolon in macro definition crypto: pkcs7: Use match_string() helper to simplify the code PKCS#7: drop function from kernel-doc pkcs7_validate_trust_one encrypted-keys: Replace HTTP links with HTTPS ones crypto: asymmetric_keys: fix some comments in pkcs7_parser.h KEYS: remove redundant memset security: keys: delete repeated words in comments KEYS: asymmetric: Fix kerneldoc security/keys: use kvfree_sensitive() watch_queue: Drop references to /dev/watch_queue keys: Remove outdated __user annotations security: keys: Fix fall-through warnings for Clang
2021-01-21watch_queue: Drop references to /dev/watch_queueGabriel Krisman Bertazi1-2/+2
The merged API doesn't use a watch_queue device, but instead relies on pipes, so let the documentation reflect that. Fixes: f7e47677e39a ("watch_queue: Add a key/keyring notification facility") Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Ben Boeckel <mathstuf@gmail.com>
2021-01-11Documentation: Replace lkml.org links with loreJoe Perches1-1/+1
Replace the lkml.org links with lore to better use a single source that's more likely to stay available long-term. Done by bash script: cvt_lkml_to_lore () { tmpfile=$(mktemp ./.cvt_links.XXXXXXX) header=$(echo $1 | sed 's@/lkml/@/lkml/headers/@') wget -qO - $header > $tmpfile if [[ $? == 0 ]] ; then link=$(grep -i '^Message-Id:' $tmpfile | head -1 | \ sed -r -e 's/^\s*Message-Id:\s*<\s*//' -e 's/\s*>\s*$//' -e 's@^@https://lore.kernel.org/r/@') # echo "testlink: $link" if [ -n "$link" ] ; then wget -qO - $link > /dev/null if [[ $? == 0 ]] ; then echo $link fi fi fi rm -f $tmpfile } git grep -P -o "\bhttps?://(?:www.)?lkml.org/lkml[\/\w]+" $@ | while read line ; do echo $line file=$(echo $line | cut -f1 -d':') link=$(echo $line | cut -f2- -d':') newlink=$(cvt_lkml_to_lore $link) if [[ -n "$newlink" ]] ; then sed -i -e "s#\b$link\b#$newlink#" $file fi done Link: https://lore.kernel.org/patchwork/patch/1265849/#1462688 Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/77cdb7f32cfb087955bfc3600b86c40bed5d4104.camel@perches.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-09Documentation: remove current_security() referenceDenis Efremov1-1/+0
Commit 15322a0d90b6 ("lsm: remove current_security()") removed current_security() from the sources. Signed-off-by: Denis Efremov <efremov@linux.com> Link: https://lore.kernel.org/r/20200830142509.5738-1-efremov@linux.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-09docs: trusted-encrypted.rst: update parameters for command examplesColy Li1-3/+2
The parameters in command examples for tpm2_createprimary and tpm2_evictcontrol are outdated, people (like me) are not able to create trusted key by these command examples. This patch updates the parameters of command example tpm2_createprimary and tpm2_evictcontrol in trusted-encrypted.rst. With Linux kernel v5.8 and tpm2-tools-4.1, people can create a trusted key by following the examples in this document. Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: James Bottomley <jejb@linux.ibm.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Peter Huewe <peterhuewe@gmx.de> Link: https://lore.kernel.org/r/20200821135356.15737-1-colyli@suse.de Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-13Documentation: security/keys: eliminate duplicated wordRandy Dunlap1-1/+1
Drop the doubled word "in". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: James Bottomley <jejb@linux.ibm.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: linux-integrity@vger.kernel.org Cc: keyrings@vger.kernel.org Link: https://lore.kernel.org/r/20200707180414.10467-19-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-06Security: Documentation: Replace deprecated :c:func: UsagePuranjay Mohan1-3/+3
Replace :c:func: with ``func()`` as the previous usage is deprecated. Remove an extra ')' to fix broken cross reference. Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20200706184956.6928-1-puranjay12@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-05Documentation: Clarify f_cred vs current_cred() useKees Cook1-0/+4
When making access control choices from a file-based context, f_cred must be used instead of current_cred() to avoid confused deputy attacks where an open file may get passed to a more privileged process. Add a short paragraph to explicitly state the rationale. Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/202007031038.8833A35DE4@keescook Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-19docs: crypto: convert asymmetric-keys.txt to ReSTMauro Carvalho Chehab1-1/+1
This file is almost compatible with ReST. Just minor changes were needed: - Adjust document and titles markups; - Adjust numbered list markups; - Add a comments markup for the Contents section; - Add markups for literal blocks. Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/c2275ea94e0507a01b020ab66dfa824d8b1c2545.1592203650.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-13Merge tag 'notifications-20200601' of ↵Linus Torvalds1-0/+57
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull notification queue from David Howells: "This adds a general notification queue concept and adds an event source for keys/keyrings, such as linking and unlinking keys and changing their attributes. Thanks to Debarshi Ray, we do have a pull request to use this to fix a problem with gnome-online-accounts - as mentioned last time: https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47 Without this, g-o-a has to constantly poll a keyring-based kerberos cache to find out if kinit has changed anything. [ There are other notification pending: mount/sb fsinfo notifications for libmount that Karel Zak and Ian Kent have been working on, and Christian Brauner would like to use them in lxc, but let's see how this one works first ] LSM hooks are included: - A set of hooks are provided that allow an LSM to rule on whether or not a watch may be set. Each of these hooks takes a different "watched object" parameter, so they're not really shareable. The LSM should use current's credentials. [Wanted by SELinux & Smack] - A hook is provided to allow an LSM to rule on whether or not a particular message may be posted to a particular queue. This is given the credentials from the event generator (which may be the system) and the watch setter. [Wanted by Smack] I've provided SELinux and Smack with implementations of some of these hooks. WHY === Key/keyring notifications are desirable because if you have your kerberos tickets in a file/directory, your Gnome desktop will monitor that using something like fanotify and tell you if your credentials cache changes. However, we also have the ability to cache your kerberos tickets in the session, user or persistent keyring so that it isn't left around on disk across a reboot or logout. Keyrings, however, cannot currently be monitored asynchronously, so the desktop has to poll for it - not so good on a laptop. This facility will allow the desktop to avoid the need to poll. DESIGN DECISIONS ================ - The notification queue is built on top of a standard pipe. Messages are effectively spliced in. The pipe is opened with a special flag: pipe2(fds, O_NOTIFICATION_PIPE); The special flag has the same value as O_EXCL (which doesn't seem like it will ever be applicable in this context)[?]. It is given up front to make it a lot easier to prohibit splice&co from accessing the pipe. [?] Should this be done some other way? I'd rather not use up a new O_* flag if I can avoid it - should I add a pipe3() system call instead? The pipe is then configured:: ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth); ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter); Messages are then read out of the pipe using read(). - It should be possible to allow write() to insert data into the notification pipes too, but this is currently disabled as the kernel has to be able to insert messages into the pipe *without* holding pipe->mutex and the code to make this work needs careful auditing. - sendfile(), splice() and vmsplice() are disabled on notification pipes because of the pipe->mutex issue and also because they sometimes want to revert what they just did - but one or more notification messages might've been interleaved in the ring. - The kernel inserts messages with the wait queue spinlock held. This means that pipe_read() and pipe_write() have to take the spinlock to update the queue pointers. - Records in the buffer are binary, typed and have a length so that they can be of varying size. This allows multiple heterogeneous sources to share a common buffer; there are 16 million types available, of which I've used just a few, so there is scope for others to be used. Tags may be specified when a watchpoint is created to help distinguish the sources. - Records are filterable as types have up to 256 subtypes that can be individually filtered. Other filtration is also available. - Notification pipes don't interfere with each other; each may be bound to a different set of watches. Any particular notification will be copied to all the queues that are currently watching for it - and only those that are watching for it. - When recording a notification, the kernel will not sleep, but will rather mark a queue as having lost a message if there's insufficient space. read() will fabricate a loss notification message at an appropriate point later. - The notification pipe is created and then watchpoints are attached to it, using one of: keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01); watch_mount(AT_FDCWD, "/", 0, fd, 0x02); watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03); where in both cases, fd indicates the queue and the number after is a tag between 0 and 255. - Watches are removed if either the notification pipe is destroyed or the watched object is destroyed. In the latter case, a message will be generated indicating the enforced watch removal. Things I want to avoid: - Introducing features that make the core VFS dependent on the network stack or networking namespaces (ie. usage of netlink). - Dumping all this stuff into dmesg and having a daemon that sits there parsing the output and distributing it as this then puts the responsibility for security into userspace and makes handling namespaces tricky. Further, dmesg might not exist or might be inaccessible inside a container. - Letting users see events they shouldn't be able to see. TESTING AND MANPAGES ==================== - The keyutils tree has a pipe-watch branch that has keyctl commands for making use of notifications. Proposed manual pages can also be found on this branch, though a couple of them really need to go to the main manpages repository instead. If the kernel supports the watching of keys, then running "make test" on that branch will cause the testing infrastructure to spawn a monitoring process on the side that monitors a notifications pipe for all the key/keyring changes induced by the tests and they'll all be checked off to make sure they happened. https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch - A test program is provided (samples/watch_queue/watch_test) that can be used to monitor for keyrings, mount and superblock events. Information on the notifications is simply logged to stdout" * tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: smack: Implement the watch_key and post_notification hooks selinux: Implement the watch_key security hook keys: Make the KEY_NEED_* perms an enum rather than a mask pipe: Add notification lossage handling pipe: Allow buffers to be marked read-whole-or-error for notifications Add sample notification program watch_queue: Add a key/keyring notification facility security: Add hooks to rule on setting a watch pipe: Add general notification queue support pipe: Add O_NOTIFICATION_PIPE security: Add a hook for the point of notification insertion uapi: General notification queue definitions