Commit Graph

670 Commits

Author SHA1 Message Date
Roberto Sassu
cd3cec0a02 ima: Move to LSM infrastructure
Move hardcoded IMA function calls (not appraisal-specific functions) from
various places in the kernel to the LSM infrastructure, by introducing a
new LSM named 'ima' (at the end of the LSM list and always enabled like
'integrity').

Having IMA before EVM in the Makefile is sufficient to preserve the
relative order of the new 'ima' LSM in respect to the upcoming 'evm' LSM,
and thus the order of IMA and EVM function calls as when they were
hardcoded.

Make moved functions as static (except ima_post_key_create_or_update(),
which is not in ima_main.c), and register them as implementation of the
respective hooks in the new function init_ima_lsm().

Select CONFIG_SECURITY_PATH, to ensure that the path-based LSM hook
path_post_mknod is always available and ima_post_path_mknod() is always
executed to mark files as new, as before the move.

A slight difference is that IMA and EVM functions registered for the
inode_post_setattr, inode_post_removexattr, path_post_mknod,
inode_post_create_tmpfile, inode_post_set_acl and inode_post_remove_acl
won't be executed for private inodes. Since those inodes are supposed to be
fs-internal, they should not be of interest to IMA or EVM. The S_PRIVATE
flag is used for anonymous inodes, hugetlbfs, reiserfs xattrs, XFS scrub
and kernel-internal tmpfs files.

Conditionally register ima_post_key_create_or_update() if
CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Also, conditionally register
ima_kernel_module_request() if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled.

Finally, add the LSM_ID_IMA case in lsm_list_modules_test.c.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-02-15 23:43:46 -05:00
Roberto Sassu
b8d997032a security: Introduce key_post_create_or_update hook
In preparation for moving IMA and EVM to the LSM infrastructure, introduce
the key_post_create_or_update hook.

Depending on policy, IMA measures the key content after creation or update,
so that remote verifiers are aware of the operation.

Other LSMs could similarly take some action after successful key creation
or update.

The new hook cannot return an error and cannot cause the operation to be
reverted.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-02-15 23:43:45 -05:00
Mimi Zohar
1ed4b56310 Revert "KEYS: encrypted: Add check for strsep"
This reverts commit b4af096b5d.

New encrypted keys are created either from kernel-generated random
numbers or user-provided decrypted data.  Revert the change requiring
user-provided decrypted data.

Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2024-01-24 16:11:59 -05:00
Linus Torvalds
6c1dd1fe5d Merge tag 'integrity-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:

 - Add a new IMA/EVM maintainer and reviewer

 - Disable EVM on overlayfs

   The EVM HMAC and the original file signatures contain filesystem
   specific metadata (e.g. i_ino, i_generation and s_uuid), preventing
   the security.evm xattr from directly being copied up to the overlay.
   Further before calculating and writing out the overlay file's EVM
   HMAC, EVM must first verify the existing backing file's
   'security.evm' value.

   For now until a solution is developed, disable EVM on overlayfs.

 - One bug fix and two cleanups

* tag 'integrity-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  overlay: disable EVM
  evm: add support to disable EVM on unsupported filesystems
  evm: don't copy up 'security.evm' xattr
  MAINTAINERS: Add Eric Snowberg as a reviewer to IMA
  MAINTAINERS: Add Roberto Sassu as co-maintainer to IMA and EVM
  KEYS: encrypted: Add check for strsep
  ima: Remove EXPERIMENTAL from Kconfig
  ima: Reword IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY
2024-01-09 13:24:06 -08:00
Linus Torvalds
5db8752c3b Merge tag 'vfs-6.8.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs iov_iter cleanups from Christian Brauner:
 "This contains a minor cleanup. The patches drop an unused argument
  from import_single_range() allowing to replace import_single_range()
  with import_ubuf() and dropping import_single_range() completely"

* tag 'vfs-6.8.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  iov_iter: replace import_single_range() with import_ubuf()
  iov_iter: remove unused 'iov' argument from import_single_range()
2024-01-08 11:43:04 -08:00
David Howells
39299bdd25 keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry
If a key has an expiration time, then when that time passes, the key is
left around for a certain amount of time before being collected (5 mins by
default) so that EKEYEXPIRED can be returned instead of ENOKEY.  This is a
problem for DNS keys because we want to redo the DNS lookup immediately at
that point.

Fix this by allowing key types to be marked such that keys of that type
don't have this extra period, but are reclaimed as soon as they expire and
turn this on for dns_resolver-type keys.  To make this easier to handle,
key->expiry is changed to be permanent if TIME64_MAX rather than 0.

Furthermore, give such new-style negative DNS results a 1s default expiry
if no other expiry time is set rather than allowing it to stick around
indefinitely.  This shouldn't be zero as ls will follow a failing stat call
immediately with a second with AT_SYMLINK_NOFOLLOW added.

Fixes: 1a4240f476 ("DNS: Separate out CIFS DNS Resolver code")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: Wang Lei <wang840925@gmail.com>
cc: Jeff Layton <jlayton@redhat.com>
cc: Steve French <smfrench@gmail.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: keyrings@vger.kernel.org
cc: netdev@vger.kernel.org
2023-12-21 13:47:38 +00:00
Jens Axboe
9fd7874c0e iov_iter: replace import_single_range() with import_ubuf()
With the removal of the 'iov' argument to import_single_range(), the two
functions are now fully identical. Convert the import_single_range()
callers to import_ubuf(), and remove the former fully.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20231204174827.1258875-3-axboe@kernel.dk
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-05 11:57:37 +01:00
Jens Axboe
6ac805d138 iov_iter: remove unused 'iov' argument from import_single_range()
It is entirely unused, just get rid of it.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20231204174827.1258875-2-axboe@kernel.dk
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-05 11:57:34 +01:00
Chen Ni
b4af096b5d KEYS: encrypted: Add check for strsep
Add check for strsep() in order to transfer the error.

Fixes: cd3bc044af ("KEYS: encrypted: Instantiate key with user-provided decrypted data")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-11-27 12:44:47 -05:00
Linus Torvalds
bc3012f4e3 Merge tag 'v6.7-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Add virtual-address based lskcipher interface
   - Optimise ahash/shash performance in light of costly indirect calls
   - Remove ahash alignmask attribute

  Algorithms:
   - Improve AES/XTS performance of 6-way unrolling for ppc
   - Remove some uses of obsolete algorithms (md4, md5, sha1)
   - Add FIPS 202 SHA-3 support in pkcs1pad
   - Add fast path for single-page messages in adiantum
   - Remove zlib-deflate

  Drivers:
   - Add support for S4 in meson RNG driver
   - Add STM32MP13x support in stm32
   - Add hwrng interface support in qcom-rng
   - Add support for deflate algorithm in hisilicon/zip"

* tag 'v6.7-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (283 commits)
  crypto: adiantum - flush destination page before unmapping
  crypto: testmgr - move pkcs1pad(rsa,sha3-*) to correct place
  Documentation/module-signing.txt: bring up to date
  module: enable automatic module signing with FIPS 202 SHA-3
  crypto: asymmetric_keys - allow FIPS 202 SHA-3 signatures
  crypto: rsa-pkcs1pad - Add FIPS 202 SHA-3 support
  crypto: FIPS 202 SHA-3 register in hash info for IMA
  x509: Add OIDs for FIPS 202 SHA-3 hash and signatures
  crypto: ahash - optimize performance when wrapping shash
  crypto: ahash - check for shash type instead of not ahash type
  crypto: hash - move "ahash wrapping shash" functions to ahash.c
  crypto: talitos - stop using crypto_ahash::init
  crypto: chelsio - stop using crypto_ahash::init
  crypto: ahash - improve file comment
  crypto: ahash - remove struct ahash_request_priv
  crypto: ahash - remove crypto_ahash_alignmask
  crypto: gcm - stop using alignmask of ahash
  crypto: chacha20poly1305 - stop using alignmask of ahash
  crypto: ccm - stop using alignmask of ahash
  net: ipv6: stop checking crypto_ahash_alignmask
  ...
2023-11-02 16:15:30 -10:00
Linus Torvalds
90d624af2e Merge tag 'for-6.7/block-2023-10-30' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:

 - Improvements to the queue_rqs() support, and adding null_blk support
   for that as well (Chengming)

 - Series improving badblocks support (Coly)

 - Key store support for sed-opal (Greg)

 - IBM partition string handling improvements (Jan)

 - Make number of ublk devices supported configurable (Mike)

 - Cancelation improvements for ublk (Ming)

 - MD pull requests via Song:
     - Handle timeout in md-cluster, by Denis Plotnikov
     - Cleanup pers->prepare_suspend, by Yu Kuai
     - Rewrite mddev_suspend(), by Yu Kuai
     - Simplify md_seq_ops, by Yu Kuai
     - Reduce unnecessary locking array_state_store(), by Mariusz
       Tkaczyk
     - Make rdev add/remove independent from daemon thread, by Yu Kuai
     - Refactor code around quiesce() and mddev_suspend(), by Yu Kuai

 - NVMe pull request via Keith:
     - nvme-auth updates (Mark)
     - nvme-tcp tls (Hannes)
     - nvme-fc annotaions (Kees)

 - Misc cleanups and improvements (Jiapeng, Joel)

* tag 'for-6.7/block-2023-10-30' of git://git.kernel.dk/linux: (95 commits)
  block: ublk_drv: Remove unused function
  md: cleanup pers->prepare_suspend()
  nvme-auth: allow mixing of secret and hash lengths
  nvme-auth: use transformed key size to create resp
  nvme-auth: alloc nvme_dhchap_key as single buffer
  nvmet-tcp: use 'spin_lock_bh' for state_lock()
  powerpc/pseries: PLPKS SED Opal keystore support
  block: sed-opal: keystore access for SED Opal keys
  block:sed-opal: SED Opal keystore
  ublk: simplify aborting request
  ublk: replace monitor with cancelable uring_cmd
  ublk: quiesce request queue when aborting queue
  ublk: rename mm_lock as lock
  ublk: move ublk_cancel_dev() out of ub->mutex
  ublk: make sure io cmd handled in submitter task context
  ublk: don't get ublk device reference in ublk_abort_queue()
  ublk: Make ublks_max configurable
  ublk: Limit dev_id/ub_number values
  md-cluster: check for timeout while a new disk adding
  nvme: rework NVME_AUTH Kconfig selection
  ...
2023-11-01 12:30:07 -10:00
YueHaibing
03acb9ccec keys: Remove unused extern declarations
Since commit b2a4df200d ("KEYS: Expand the capacity of a keyring")
iterate_over_keyring() is never used, so can be removed.

And commit b5f545c880 ("[PATCH] keys: Permit running process to instantiate keys")
left behind keyring_search_instkey().

Fixes: b2a4df200d ("KEYS: Expand the capacity of a keyring")
Fixes: b5f545c880 ("[PATCH] keys: Permit running process to instantiate keys")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-10-24 03:16:52 +03:00
Sumit Garg
c745cd1718 KEYS: trusted: tee: Refactor register SHM usage
The OP-TEE driver using the old SMC based ABI permits overlapping shared
buffers, but with the new FF-A based ABI each physical page may only
be registered once.

As the key and blob buffer are allocated adjancently, there is no need
for redundant register shared memory invocation. Also, it is incompatibile
with FF-A based ABI limitation. So refactor register shared memory
implementation to use only single invocation to register both key and blob
buffers.

[jarkko: Added cc to stable.]
Cc: stable@vger.kernel.org # v5.16+
Fixes: 4615e5a34b ("optee: add FF-A support")
Reported-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-10-24 03:06:35 +03:00
Jarkko Sakkinen
31de287345 KEYS: trusted: Rollback init_trusted() consistently
Do bind neither static calls nor trusted_key_exit() before a successful
init, in order to maintain a consistent state. In addition, depart the
init_trusted() in the case of a real error (i.e. getting back something
else than -ENODEV).

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Closes: https://lore.kernel.org/linux-integrity/CAHk-=whOPoLaWM8S8GgoOPT7a2+nMH5h3TLKtn=R_3w4R1_Uvg@mail.gmail.com/
Cc: stable@vger.kernel.org # v5.13+
Fixes: 5d0682be31 ("KEYS: trusted: Add generic trusted keys framework")
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-10-24 03:06:06 +03:00
Hannes Reinecke
037c34318a security/keys: export key_lookup()
For in-kernel consumers one cannot readily assign a user (eg when
running from a workqueue), so the normal key search permissions
cannot be applied.
This patch exports the 'key_lookup()' function for a simple lookup
of keys without checking for permissions.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2023-10-11 10:11:54 -07:00
Sumit Garg
01bbafc63b KEYS: trusted: Remove redundant static calls usage
Static calls invocations aren't well supported from module __init and
__exit functions. Especially the static call from cleanup_trusted() led
to a crash on x86 kernel with CONFIG_DEBUG_VIRTUAL=y.

However, the usage of static call invocations for trusted_key_init()
and trusted_key_exit() don't add any value from either a performance or
security perspective. Hence switch to use indirect function calls instead.

Note here that although it will fix the current crash report, ultimately
the static call infrastructure should be fixed to either support its
future usage from module __init and __exit functions or not.

Reported-and-tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Link: https://lore.kernel.org/lkml/ZRhKq6e5nF%2F4ZIV1@fedora/#t
Fixes: 5d0682be31 ("KEYS: trusted: Add generic trusted keys framework")
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-10-10 11:19:43 -07:00
Herbert Xu
fb3bc06ad8 KEYS: encrypted: Do not include crypto/algapi.h
The header file crypto/algapi.h is for internal use only.  Use the
header file crypto/utils.h instead.

Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2023-09-15 18:30:43 +08:00
Azeem Shaikh
604b8e7558 KEYS: Replace all non-returning strlcpy with strscpy
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-08-17 20:12:35 +00:00
Tom Rix
0de030b308 sysctl: set variable key_sysctls storage-class-specifier to static
smatch reports
security/keys/sysctl.c:12:18: warning: symbol
  'key_sysctls' was not declared. Should it be static?

This variable is only used in its defining file, so it should be static.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-08-07 17:55:54 +00:00
Christian Göttsche
2d7f105edb security: keys: perform capable check only on privileged operations
If the current task fails the check for the queried capability via
`capable(CAP_SYS_ADMIN)` LSMs like SELinux generate a denial message.
Issuing such denial messages unnecessarily can lead to a policy author
granting more privileges to a subject than needed to silence them.

Reorder CAP_SYS_ADMIN checks after the check whether the operation is
actually privileged.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-07-28 18:07:41 +00:00
Jiapeng Chong
2a41527420 security: keys: Modify mismatched function name
No functional modification involved.

security/keys/trusted-keys/trusted_tpm2.c:203: warning: expecting prototype for tpm_buf_append_auth(). Prototype was for tpm2_buf_append_auth() instead.

Fixes: 2e19e10131 ("KEYS: trusted: Move TPM2 trusted keys code")
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=5524
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-07-17 19:40:27 +00:00
Petr Pavlu
d55901522f keys: Fix linking a duplicate key to a keyring's assoc_array
When making a DNS query inside the kernel using dns_query(), the request
code can in rare cases end up creating a duplicate index key in the
assoc_array of the destination keyring. It is eventually found by
a BUG_ON() check in the assoc_array implementation and results in
a crash.

Example report:
[2158499.700025] kernel BUG at ../lib/assoc_array.c:652!
[2158499.700039] invalid opcode: 0000 [#1] SMP PTI
[2158499.700065] CPU: 3 PID: 31985 Comm: kworker/3:1 Kdump: loaded Not tainted 5.3.18-150300.59.90-default #1 SLE15-SP3
[2158499.700096] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[2158499.700351] Workqueue: cifsiod cifs_resolve_server [cifs]
[2158499.700380] RIP: 0010:assoc_array_insert+0x85f/0xa40
[2158499.700401] Code: ff 74 2b 48 8b 3b 49 8b 45 18 4c 89 e6 48 83 e7 fe e8 95 ec 74 00 3b 45 88 7d db 85 c0 79 d4 0f 0b 0f 0b 0f 0b e8 41 f2 be ff <0f> 0b 0f 0b 81 7d 88 ff ff ff 7f 4c 89 eb 4c 8b ad 58 ff ff ff 0f
[2158499.700448] RSP: 0018:ffffc0bd6187faf0 EFLAGS: 00010282
[2158499.700470] RAX: ffff9f1ea7da2fe8 RBX: ffff9f1ea7da2fc1 RCX: 0000000000000005
[2158499.700492] RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000000
[2158499.700515] RBP: ffffc0bd6187fbb0 R08: ffff9f185faf1100 R09: 0000000000000000
[2158499.700538] R10: ffff9f1ea7da2cc0 R11: 000000005ed8cec8 R12: ffffc0bd6187fc28
[2158499.700561] R13: ffff9f15feb8d000 R14: ffff9f1ea7da2fc0 R15: ffff9f168dc0d740
[2158499.700585] FS:  0000000000000000(0000) GS:ffff9f185fac0000(0000) knlGS:0000000000000000
[2158499.700610] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[2158499.700630] CR2: 00007fdd94fca238 CR3: 0000000809d8c006 CR4: 00000000003706e0
[2158499.700702] Call Trace:
[2158499.700741]  ? key_alloc+0x447/0x4b0
[2158499.700768]  ? __key_link_begin+0x43/0xa0
[2158499.700790]  __key_link_begin+0x43/0xa0
[2158499.700814]  request_key_and_link+0x2c7/0x730
[2158499.700847]  ? dns_resolver_read+0x20/0x20 [dns_resolver]
[2158499.700873]  ? key_default_cmp+0x20/0x20
[2158499.700898]  request_key_tag+0x43/0xa0
[2158499.700926]  dns_query+0x114/0x2ca [dns_resolver]
[2158499.701127]  dns_resolve_server_name_to_ip+0x194/0x310 [cifs]
[2158499.701164]  ? scnprintf+0x49/0x90
[2158499.701190]  ? __switch_to_asm+0x40/0x70
[2158499.701211]  ? __switch_to_asm+0x34/0x70
[2158499.701405]  reconn_set_ipaddr_from_hostname+0x81/0x2a0 [cifs]
[2158499.701603]  cifs_resolve_server+0x4b/0xd0 [cifs]
[2158499.701632]  process_one_work+0x1f8/0x3e0
[2158499.701658]  worker_thread+0x2d/0x3f0
[2158499.701682]  ? process_one_work+0x3e0/0x3e0
[2158499.701703]  kthread+0x10d/0x130
[2158499.701723]  ? kthread_park+0xb0/0xb0
[2158499.701746]  ret_from_fork+0x1f/0x40

The situation occurs as follows:
* Some kernel facility invokes dns_query() to resolve a hostname, for
  example, "abcdef". The function registers its global DNS resolver
  cache as current->cred.thread_keyring and passes the query to
  request_key_net() -> request_key_tag() -> request_key_and_link().
* Function request_key_and_link() creates a keyring_search_context
  object. Its match_data.cmp method gets set via a call to
  type->match_preparse() (resolves to dns_resolver_match_preparse()) to
  dns_resolver_cmp().
* Function request_key_and_link() continues and invokes
  search_process_keyrings_rcu() which returns that a given key was not
  found. The control is then passed to request_key_and_link() ->
  construct_alloc_key().
* Concurrently to that, a second task similarly makes a DNS query for
  "abcdef." and its result gets inserted into the DNS resolver cache.
* Back on the first task, function construct_alloc_key() first runs
  __key_link_begin() to determine an assoc_array_edit operation to
  insert a new key. Index keys in the array are compared exactly as-is,
  using keyring_compare_object(). The operation finds that "abcdef" is
  not yet present in the destination keyring.
* Function construct_alloc_key() continues and checks if a given key is
  already present on some keyring by again calling
  search_process_keyrings_rcu(). This search is done using
  dns_resolver_cmp() and "abcdef" gets matched with now present key
  "abcdef.".
* The found key is linked on the destination keyring by calling
  __key_link() and using the previously calculated assoc_array_edit
  operation. This inserts the "abcdef." key in the array but creates
  a duplicity because the same index key is already present.

Fix the problem by postponing __key_link_begin() in
construct_alloc_key() until an actual key which should be linked into
the destination keyring is determined.

[jarkko@kernel.org: added a fixes tag and cc to stable]
Cc: stable@vger.kernel.org # v5.3+
Fixes: df593ee23e ("keys: Hoist locking out of __key_link_begin()")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Joey Lee <jlee@suse.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-07-17 19:32:30 +00:00
Luis Chamberlain
28898e260a sysctl: move security keys sysctl registration to its own file
The security keys sysctls are already declared on its own file,
just move the sysctl registration to its own file to help avoid
merge conflicts on sysctls.c, and help with clearing up sysctl.c
further.

This creates a small penalty of 23 bytes:

./scripts/bloat-o-meter vmlinux.1 vmlinux.2
add/remove: 2/0 grow/shrink: 0/1 up/down: 49/-26 (23)
Function                                     old     new   delta
init_security_keys_sysctls                     -      33     +33
__pfx_init_security_keys_sysctls               -      16     +16
sysctl_init_bases                             85      59     -26
Total: Before=21256937, After=21256960, chg +0.00%

But soon we'll be saving tons of bytes anyway, as we modify the
sysctl registrations to use ARRAY_SIZE and so we get rid of all the
empty array elements so let's just clean this up now.

Reviewed-by: Paul Moore <paul@paul-moore.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-06-08 15:42:02 -07:00
David Howells
47f9e4c924 keys: Do not cache key in task struct if key is requested from kernel thread
The key which gets cached in task structure from a kernel thread does not
get invalidated even after expiry.  Due to which, a new key request from
kernel thread will be served with the cached key if it's present in task
struct irrespective of the key validity.  The change is to not cache key in
task_struct when key requested from kernel thread so that kernel thread
gets a valid key on every key request.

The problem has been seen with the cifs module doing DNS lookups from a
kernel thread and the results getting pinned by being attached to that
kernel thread's cache - and thus not something that can be easily got rid
of.  The cache would ordinarily be cleared by notify-resume, but kernel
threads don't do that.

This isn't seen with AFS because AFS is doing request_key() within the
kernel half of a user thread - which will do notify-resume.

Fixes: 7743c48e54 ("keys: Cache result of request_key*() temporarily in task_struct")
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Steve French <smfrench@gmail.com>
cc: keyrings@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/CAGypqWw951d=zYRbdgNR4snUDvJhWL=q3=WOyh7HhSJupjz2vA@mail.gmail.com/
2023-03-21 16:22:40 +00:00
Linus Torvalds
36289a03bc Merge tag 'v6.3-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "API:
   - Use kmap_local instead of kmap_atomic
   - Change request callback to take void pointer
   - Print FIPS status in /proc/crypto (when enabled)

  Algorithms:
   - Add rfc4106/gcm support on arm64
   - Add ARIA AVX2/512 support on x86

  Drivers:
   - Add TRNG driver for StarFive SoC
   - Delete ux500/hash driver (subsumed by stm32/hash)
   - Add zlib support in qat
   - Add RSA support in aspeed"

* tag 'v6.3-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (156 commits)
  crypto: x86/aria-avx - Do not use avx2 instructions
  crypto: aspeed - Fix modular aspeed-acry
  crypto: hisilicon/qm - fix coding style issues
  crypto: hisilicon/qm - update comments to match function
  crypto: hisilicon/qm - change function names
  crypto: hisilicon/qm - use min() instead of min_t()
  crypto: hisilicon/qm - remove some unused defines
  crypto: proc - Print fips status
  crypto: crypto4xx - Call dma_unmap_page when done
  crypto: octeontx2 - Fix objects shared between several modules
  crypto: nx - Fix sparse warnings
  crypto: ecc - Silence sparse warning
  tls: Pass rec instead of aead_req into tls_encrypt_done
  crypto: api - Remove completion function scaffolding
  tls: Remove completion function scaffolding
  tipc: Remove completion function scaffolding
  net: ipv6: Remove completion function scaffolding
  net: ipv4: Remove completion function scaffolding
  net: macsec: Remove completion function scaffolding
  dm: Remove completion function scaffolding
  ...
2023-02-21 18:10:50 -08:00