14 Dec, 2020
1 commit
-
Secure keys are derieved using CAAM crypto block.
Secure keys derieved are the random number symmetric keys from CAAM.
Blobs corresponding to the key are formed using CAAM. User space
will only be able to view the blob of the key.Signed-off-by: Udit Agarwal
Reviewed-by: Sahil Malhotra
[ Aisheng: fix minior conflicts due to
47f9c2796891 ("KEYS: trusted: Create trusted keys subsystem") ]
Sign-off-by: Dong Aisheng
10 Sep, 2020
2 commits
-
Commit 15322a0d90b6 ("lsm: remove current_security()") removed
current_security() from the sources.Signed-off-by: Denis Efremov
Link: https://lore.kernel.org/r/20200830142509.5738-1-efremov@linux.com
Signed-off-by: Jonathan Corbet -
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tpm2_evictcontrol are outdated, people (like me) are not able to create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
Reviewed-by: Jarkko Sakkinen
Reviewed-by: Stefan Berger
Cc: Dan Williams
Cc: James Bottomley
Cc: Jason Gunthorpe
Cc: Mimi Zohar
Cc: Peter Huewe
Link: https://lore.kernel.org/r/20200821135356.15737-1-colyli@suse.de
Signed-off-by: Jonathan Corbet
13 Jul, 2020
1 commit
-
Drop the doubled word "in".
Signed-off-by: Randy Dunlap
Acked-by: Jarkko Sakkinen
Cc: Jonathan Corbet
Cc: linux-doc@vger.kernel.org
Cc: James Bottomley
Cc: Jarkko Sakkinen
Cc: Mimi Zohar
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
07 Jul, 2020
1 commit
-
Replace :c:func: with ``func()`` as the previous usage is deprecated.
Remove an extra ')' to fix broken cross reference.Signed-off-by: Puranjay Mohan
Link: https://lore.kernel.org/r/20200706184956.6928-1-puranjay12@gmail.com
Signed-off-by: Jonathan Corbet
06 Jul, 2020
1 commit
-
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
Cc: linux-doc@vger.kernel.org
Signed-off-by: Kees Cook
Link: https://lore.kernel.org/r/202007031038.8833A35DE4@keescook
Signed-off-by: Jonathan Corbet
20 Jun, 2020
1 commit
-
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
Signed-off-by: Mauro Carvalho Chehab
Link: https://lore.kernel.org/r/c2275ea94e0507a01b020ab66dfa824d8b1c2545.1592203650.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet
14 Jun, 2020
1 commit
-
…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
11 Jun, 2020
1 commit
-
Pull more documentation updates from Jonathan Corbet:
"A handful of late-arriving docs fixes, along with a patch changing a
lot of HTTP links to HTTPS that had to be yanked and redone before the
first pull"* tag 'docs-5.8-2' of git://git.lwn.net/linux:
docs/memory-barriers.txt/kokr: smp_mb__{before,after}_atomic(): update Documentation
Documentation: devres: add missing entry for devm_platform_get_and_ioremap_resource()
Replace HTTP links with HTTPS ones: documentation
docs: it_IT: address invalid reference warnings
doc: zh_CN: use doc reference to resolve undefined label warning
docs: Update the location of the LF NDA program
docs: dev-tools: coccinelle: underlines
08 Jun, 2020
1 commit
-
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.Deterministic algorithm:
For each file:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.Signed-off-by: Alexander A. Klimov
Link: https://lore.kernel.org/r/20200526060544.25127-1-grandmaster@al2klimov.de
Signed-off-by: Jonathan Corbet
05 Jun, 2020
1 commit
-
Pull keyring updates from David Howells:
- Fix a documentation warning.
- Replace a zero-length array with a flexible one
- Make the big_key key type use ChaCha20Poly1305 and use the crypto
algorithm directly rather than going through the crypto layer.- Implement the update op for the big_key type.
* tag 'keys-next-20200602' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
keys: Implement update for the big_key type
security/keys: rewrite big_key crypto to use library interface
KEYS: Replace zero-length array with flexible-array
Documentation: security: core.rst: add missing argument
03 Jun, 2020
1 commit
-
This argument was just never documented in the first place.
Signed-off-by: Ben Boeckel
Signed-off-by: David Howells
Reviewed-by: Jarkko Sakkinen
02 Jun, 2020
1 commit
-
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
...
26 May, 2020
1 commit
-
This is a first pass at updating the basic documentation on
Linux Security Modules (LSM), which is frighteningly out of date.
Remove untrue statements about the LSM framework. Replace them
with true statements where it is convenient to do so. This is
the beginnig of a larger effort to bring the LSM documentation
up to date.Signed-off-by: Casey Schaufler
Link: https://lore.kernel.org/r/4c053d72-2d58-612f-6d6b-f04226d0181e@schaufler-ca.com
Signed-off-by: Jonathan Corbet
19 May, 2020
1 commit
-
Add a key/keyring change notification facility whereby notifications about
changes in key and keyring content and attributes can be received.Firstly, an event queue needs to be created:
pipe2(fds, O_NOTIFICATION_PIPE);
ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, 256);then a notification can be set up to report notifications via that queue:
struct watch_notification_filter filter = {
.nr_filters = 1,
.filters = {
[0] = {
.type = WATCH_TYPE_KEY_NOTIFY,
.subtype_filter[0] = UINT_MAX,
},
},
};
ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter);
keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);After that, records will be placed into the queue when events occur in
which keys are changed in some way. Records are of the following format:struct key_notification {
struct watch_notification watch;
__u32 key_id;
__u32 aux;
} *n;Where:
n->watch.type will be WATCH_TYPE_KEY_NOTIFY.
n->watch.subtype will indicate the type of event, such as
NOTIFY_KEY_REVOKED.n->watch.info & WATCH_INFO_LENGTH will indicate the length of the
record.n->watch.info & WATCH_INFO_ID will be the second argument to
keyctl_watch_key(), shifted.n->key will be the ID of the affected key.
n->aux will hold subtype-dependent information, such as the key
being linked into the keyring specified by n->key in the case of
NOTIFY_KEY_LINKED.Note that it is permissible for event records to be of variable length -
or, at least, the length may be dependent on the subtype. Note also that
the queue can be shared between multiple notifications of various types.Signed-off-by: David Howells
Reviewed-by: James Morris
16 May, 2020
1 commit
-
Signed-off-by: Mauro Carvalho Chehab
Link: https://lore.kernel.org/r/6af5365404c7bd9d008e7e3a77ba83587fd33012.1588345503.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet
08 May, 2020
1 commit
-
The library implementation of the SHA-1 compression function is
confusingly called just "sha_transform()". Alongside it are some "SHA_"
constants and "sha_init()". Presumably these are left over from a time
when SHA just meant SHA-1. But now there are also SHA-2 and SHA-3, and
moreover SHA-1 is now considered insecure and thus shouldn't be used.Therefore, rename these functions and constants to make it very clear
that they are for SHA-1. Also add a comment to make it clear that these
shouldn't be used.For the extra-misleadingly named "SHA_MESSAGE_BYTES", rename it to
SHA1_BLOCK_SIZE and define it to just '64' rather than '(512/8)' so that
it matches the same definition in . This prepares for
merging into .Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
21 Mar, 2020
1 commit
-
Changeset 58ad30cf91f0 ("docs: fix reference to core-api/namespaces.rst")
enabled a new feature at Sphinx: it will now generate index for each
document title, plus to each chapter inside it.There's a drawback, though: one document cannot have two sections
with the same name anymore.A followup patch will change the logic of autosectionlabel to
avoid most creating references for every single section title,
but still we need to be able to reference the chapters inside
a document.There are a few places where there are two chapters with the
same name. This patch renames one of the chapters, in order to
avoid symbol conflict within the same document.PS.: as I don't speach Chinese, I had some help from a friend
(Wen Liu) at the Chinese translation for "publishing patches"
for this document:Documentation/translations/zh_CN/process/5.Posting.rst
Fixes: 58ad30cf91f0 ("docs: fix reference to core-api/namespaces.rst")
Signed-off-by: Mauro Carvalho Chehab
Link: https://lore.kernel.org/r/2bffb91e4a63d41bf5fae1c23e1e8b3bba0b8806.1584716446.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet
23 Nov, 2019
1 commit
-
Fix warnings due to missing markup, no change in content otherwise.
Signed-off-by: Daniel W. S. Almeida
Link: https://lore.kernel.org/r/20191122041806.68650-1-dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet
01 Oct, 2019
1 commit
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The reStructuredText syntax is wrong here; not sure how it was
intended but we can just use the section header as an implicit
hyperlink target, with a single "outward" underscore.Signed-off-by: Brendan Jackman
Signed-off-by: Jonathan Corbet
28 Sep, 2019
1 commit
-
Pull integrity updates from Mimi Zohar:
"The major feature in this time is IMA support for measuring and
appraising appended file signatures. In addition are a couple of bug
fixes and code cleanup to use struct_size().In addition to the PE/COFF and IMA xattr signatures, the kexec kernel
image may be signed with an appended signature, using the same
scripts/sign-file tool that is used to sign kernel modules.Similarly, the initramfs may contain an appended signature.
This contained a lot of refactoring of the existing appended signature
verification code, so that IMA could retain the existing framework of
calculating the file hash once, storing it in the IMA measurement list
and extending the TPM, verifying the file's integrity based on a file
hash or signature (eg. xattrs), and adding an audit record containing
the file hash, all based on policy. (The IMA support for appended
signatures patch set was posted and reviewed 11 times.)The support for appended signature paves the way for adding other
signature verification methods, such as fs-verity, based on a single
system-wide policy. The file hash used for verifying the signature and
the signature, itself, can be included in the IMA measurement list"* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: ima_api: Use struct_size() in kzalloc()
ima: use struct_size() in kzalloc()
sefltest/ima: support appended signatures (modsig)
ima: Fix use after free in ima_read_modsig()
MODSIGN: make new include file self contained
ima: fix freeing ongoing ahash_request
ima: always return negative code for error
ima: Store the measurement again when appraising a modsig
ima: Define ima-modsig template
ima: Collect modsig
ima: Implement support for module-style appended signatures
ima: Factor xattr_verify() out of ima_appraise_measurement()
ima: Add modsig appraise_type option for module-style appended signatures
integrity: Select CONFIG_KEYS instead of depending on it
PKCS#7: Introduce pkcs7_get_digest()
PKCS#7: Refactor verify_pkcs7_signature()
MODSIGN: Export module signature definitions
ima: initialize the "template" field with the default template
18 Sep, 2019
1 commit
-
Pull documentation updates from Jonathan Corbet:
"It's a somewhat calmer cycle for docs this time, as the churn of the
mass RST conversion is happily mostly behind us.- A new document on reproducible builds.
- We finally got around to zapping the documentation for hardware
support that was removed in 2004; one doesn't want to rush these
things.- The usual assortment of fixes, typo corrections, etc"
* tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits)
Documentation: kbuild: Add document about reproducible builds
docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi]
Documentation: Add "earlycon=sbi" to the admin guide
doc:lock: remove reference to clever use of read-write lock
devices.txt: improve entry for comedi (char major 98)
docs: mtd: Update spi nor reference driver
doc: arm64: fix grammar dtb placed in no attributes region
Documentation: sysrq: don't recommend 'S' 'U' before 'B'
mailmap: Update email address for Quentin Perret
docs: ftrace: clarify when tracing is disabled by the trace file
docs: process: fix broken link
Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title
Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command
Documentation/arm/sa1100: Remove some obsolete documentation
docs/zh_CN: update Chinese howto.rst for latexdocs making
Documentation: virt: Fix broken reference to virt tree's index
docs: Fix typo on pull requests guide
kernel-doc: Allow anonymous enum
Documentation: sphinx: Don't parse socket() as identifier reference
Documentation: sphinx: Add missing comma to list of strings
...
02 Sep, 2019
1 commit
-
Documentation briefly the new fTPM driver running inside TEE.
Signed-off-by: Sasha Levin
Reviewed-by: Jarkko Sakkinen
Signed-off-by: Jarkko Sakkinen
06 Aug, 2019
1 commit
-
Define new "d-modsig" template field which holds the digest that is
expected to match the one contained in the modsig, and also new "modsig"
template field which holds the appended file signature.Add a new "ima-modsig" defined template descriptor with the new fields as
well as the ones from the "ima-sig" descriptor.Change ima_store_measurement() to accept a struct modsig * argument so that
it can be passed along to the templates via struct ima_event_data.Suggested-by: Mimi Zohar
Signed-off-by: Thiago Jung Bauermann
Signed-off-by: Mimi Zohar
01 Aug, 2019
1 commit
-
There are some weird quirks when it comes to UEFI event log. Provide a
brief introduction to TPM event log mechanism and describe the quirks
and how they can be sorted out.Signed-off-by: Jarkko Sakkinen
Signed-off-by: Jonathan Corbet
15 Jul, 2019
2 commits
-
The following files belong to security:
Documentation/security/LSM.rst -> Documentation/security/lsm-development.rst
Documentation/lsm.txt -> Documentation/security/lsm.rst
Documentation/SAK.txt -> Documentation/security/sak.rst
Documentation/siphash.txt -> Documentation/security/siphash.rstSigned-off-by: Mauro Carvalho Chehab
-
In order to be able to add this file to the security book,
we need first to convert it to reST.While this is not part of any book, mark it as :orphan:, in order
to avoid build warnings.Signed-off-by: Mauro Carvalho Chehab
11 Jul, 2019
1 commit
-
…el/git/dhowells/linux-fs"
This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus
effectively commits7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION")
2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL")that the merge brought in).
It turns out that it breaks booting with an encrypted volume, and Eric
biggers reports that it also breaks the fscrypt tests [1] and loading of
in-kernel X.509 certificates [2].The root cause of all the breakage is likely the same, but David Howells
is off email so rather than try to work it out it's getting reverted in
order to not impact the rest of the merge window.[1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/
[2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
10 Jul, 2019
1 commit
-
Pull Documentation updates from Jonathan Corbet:
"It's been a relatively busy cycle for docs:- A fair pile of RST conversions, many from Mauro. These create more
than the usual number of simple but annoying merge conflicts with
other trees, unfortunately. He has a lot more of these waiting on
the wings that, I think, will go to you directly later on.- A new document on how to use merges and rebases in kernel repos,
and one on Spectre vulnerabilities.- Various improvements to the build system, including automatic
markup of function() references because some people, for reasons I
will never understand, were of the opinion that
:c:func:``function()`` is unattractive and not fun to type.- We now recommend using sphinx 1.7, but still support back to 1.4.
- Lots of smaller improvements, warning fixes, typo fixes, etc"
* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
docs: automarkup.py: ignore exceptions when seeking for xrefs
docs: Move binderfs to admin-guide
Disable Sphinx SmartyPants in HTML output
doc: RCU callback locks need only _bh, not necessarily _irq
docs: format kernel-parameters -- as code
Doc : doc-guide : Fix a typo
platform: x86: get rid of a non-existent document
Add the RCU docs to the core-api manual
Documentation: RCU: Add TOC tree hooks
Documentation: RCU: Rename txt files to rst
Documentation: RCU: Convert RCU UP systems to reST
Documentation: RCU: Convert RCU linked list to reST
Documentation: RCU: Convert RCU basic concepts to reST
docs: filesystems: Remove uneeded .rst extension on toctables
scripts/sphinx-pre-install: fix out-of-tree build
docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
Documentation: PGP: update for newer HW devices
Documentation: Add section about CPU vulnerabilities for Spectre
Documentation: platform: Delete x86-laptop-drivers.txt
docs: Note that :c:func: should no longer be used
...
09 Jul, 2019
1 commit
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Pull integrity updates from Mimi Zohar:
"Bug fixes, code clean up, and new features:- IMA policy rules can be defined in terms of LSM labels, making the
IMA policy dependent on LSM policy label changes, in particular LSM
label deletions. The new environment, in which IMA-appraisal is
being used, frequently updates the LSM policy and permits LSM label
deletions.- Prevent an mmap'ed shared file opened for write from also being
mmap'ed execute. In the long term, making this and other similar
changes at the VFS layer would be preferable.- The IMA per policy rule template format support is needed for a
couple of new/proposed features (eg. kexec boot command line
measurement, appended signatures, and VFS provided file hashes).- Other than the "boot-aggregate" record in the IMA measuremeent
list, all other measurements are of file data. Measuring and
storing the kexec boot command line in the IMA measurement list is
the first buffer based measurement included in the measurement
list"* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
integrity: Introduce struct evm_xattr
ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition
KEXEC: Call ima_kexec_cmdline to measure the boot command line args
IMA: Define a new template field buf
IMA: Define a new hook to measure the kexec boot command line arguments
IMA: support for per policy rule template formats
integrity: Fix __integrity_init_keyring() section mismatch
ima: Use designated initializers for struct ima_event_data
ima: use the lsm policy update notifier
LSM: switch to blocking policy update notifiers
x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY
ima: Make arch_policy_entry static
ima: prevent a file already mmap'ed write to be mmap'ed execute
x86/ima: check EFI SetupMode too
01 Jul, 2019
1 commit
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A buffer(kexec boot command line arguments) measured into IMA
measuremnt list cannot be appraised, without already being
aware of the buffer contents. Since hashes are non-reversible,
raw buffer is needed for validation or regenerating hash for
appraisal/attestation.Add support to store/read the buffer contents in HEX.
The kexec cmdline hash is stored in the "d-ng" field of the
template data. It can be verified using
sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements |
grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum- Add two new fields to ima_event_data to hold the buf and
buf_len
- Add a new template field 'buf' to be used to store/read
the buffer data.
- Updated process_buffer_meaurement to add the buffer to
ima_event_data. process_buffer_measurement added in
"Define a new IMA hook to measure the boot command line
arguments"
- Add a new template policy name ima-buf to represent
'd-ng|n-ng|buf'Signed-off-by: Prakhar Srivastava
Reviewed-by: Roberto Sassu
Reviewed-by: James Morris
Signed-off-by: Mimi Zohar
28 Jun, 2019
2 commits
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Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split. This will also allow a
greater range of subjects to represented.============
WHY DO THIS?
============The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.For SETATTR, this includes actions that are about controlling access to a
key:(1) Changing a key's ownership.
(2) Changing a key's security information.
(3) Setting a keyring's restriction.
And actions that are about managing a key's lifetime:
(4) Setting an expiry time.
(5) Revoking a key.
and (proposed) managing a key as part of a cache:
(6) Invalidating a key.
Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission. It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.As for SEARCH permission, that currently covers:
(1) Finding keys in a keyring tree during a search.
(2) Permitting keyrings to be joined.
(3) Invalidation.
But these don't really belong together either, since these actions really
need to be controlled separately.Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.===============
WHAT IS CHANGED
===============The SETATTR permission is split to create two new permissions:
(1) SET_SECURITY - which allows the key's owner, group and ACL to be
changed and a restriction to be placed on a keyring.(2) REVOKE - which allows a key to be revoked.
The SEARCH permission is split to create:
(1) SEARCH - which allows a keyring to be search and a key to be found.
(2) JOIN - which allows a keyring to be joined as a session keyring.
(3) INVAL - which allows a key to be invalidated.
The WRITE permission is also split to create:
(1) WRITE - which allows a key's content to be altered and links to be
added, removed and replaced in a keyring.(2) CLEAR - which allows a keyring to be cleared completely. This is
split out to make it possible to give just this to an administrator.(3) REVOKE - see above.
Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together. An ACE specifies a subject, such as:(*) Possessor - permitted to anyone who 'possesses' a key
(*) Owner - permitted to the key owner
(*) Group - permitted to the key group
(*) Everyone - permitted to everyoneNote that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.Further subjects may be made available by later patches.
The ACE also specifies a permissions mask. The set of permissions is now:
VIEW Can view the key metadata
READ Can read the key content
WRITE Can update/modify the key content
SEARCH Can find the key by searching/requesting
LINK Can make a link to the key
SET_SECURITY Can change owner, ACL, expiry
INVAL Can invalidate
REVOKE Can revoke
JOIN Can join this keyring
CLEAR Can clear this keyringThe KEYCTL_SETPERM function is then deprecated.
The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.The KEYCTL_INVALIDATE function then requires INVAL.
The KEYCTL_REVOKE function then requires REVOKE.
The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.======================
BACKWARD COMPATIBILITY
======================To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned
on if a keyring is being altered.The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.It will make the following mappings:
(1) INVAL, JOIN -> SEARCH
(2) SET_SECURITY -> SETATTR
(3) REVOKE -> WRITE if SETATTR isn't already set
(4) CLEAR -> WRITE
Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.=======
TESTING
=======This passes the keyutils testsuite for all but a couple of tests:
(1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
if the type doesn't have ->read(). You still can't actually read the
key.(2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
work as Other has been replaced with Everyone in the ACL.Signed-off-by: David Howells
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Create a request_key_net() function and use it to pass the network
namespace domain tag into DNS revolver keys and rxrpc/AFS keys so that keys
for different domains can coexist in the same keyring.Signed-off-by: David Howells
cc: netdev@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-afs@lists.infradead.org
27 Jun, 2019
2 commits
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Add a 'recurse' flag for keyring searches so that the flag can be omitted
and recursion disabled, thereby allowing just the nominated keyring to be
searched and none of the children.Signed-off-by: David Howells
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Kill off request_key_async{,_with_auxdata}() as they're not currently used.
Signed-off-by: David Howells
19 Jun, 2019
4 commits
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If a filesystem uses keys to hold authentication tokens, then it needs a
token for each VFS operation that might perform an authentication check -
either by passing it to the server, or using to perform a check based on
authentication data cached locally.For open files this isn't a problem, since the key should be cached in the
file struct since it represents the subject performing operations on that
file descriptor.During pathwalk, however, there isn't anywhere to cache the key, except
perhaps in the nameidata struct - but that isn't exposed to the
filesystems. Further, a pathwalk can incur a lot of operations, calling
one or more of the following, for instance:->lookup()
->permission()
->d_revalidate()
->d_automount()
->get_acl()
->getxattr()on each dentry/inode it encounters - and each one may need to call
request_key(). And then, at the end of pathwalk, it will call the actual
operation:->mkdir()
->mknod()
->getattr()
->open()
...which may need to go and get the token again.
However, it is very likely that all of the operations on a single
dentry/inode - and quite possibly a sequence of them - will all want to use
the same authentication token, which suggests that caching it would be a
good idea.To this end:
(1) Make it so that a positive result of request_key() and co. that didn't
require upcalling to userspace is cached temporarily in task_struct.(2) The cache is 1 deep, so a new result displaces the old one.
(3) The key is released by exit and by notify-resume.
(4) The cache is cleared in a newly forked process.
Signed-off-by: David Howells
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Provide a request_key_rcu() function that can be used to request a key
under RCU conditions. It can only search and check permissions; it cannot
allocate a new key, upcall or wait for an upcall to complete. It may
return a partially constructed key.Signed-off-by: David Howells
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Move the RCU locks outwards from the keyring search functions so that it
will become possible to provide an RCU-capable partial request_key()
function in a later commit.Signed-off-by: David Howells
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The request_key() syscall allows a process to gain access to the 'possessor'
permits of any key that grants it Search permission by virtue of request_key()
not checking whether a key it finds grants Link permission to the caller.Signed-off-by: David Howells
09 Jun, 2019
1 commit
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Multi-line literal markups only work when they're idented at the
same level, with is not the case here:Documentation/security/keys/core.rst:1597: WARNING: Inline literal start-string without end-string.
Documentation/security/keys/core.rst:1597: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1597: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1598: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1598: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1600: WARNING: Inline literal start-string without end-string.
Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1666: WARNING: Inline literal start-string without end-string.
Documentation/security/keys/core.rst:1666: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1666: WARNING: Inline emphasis start-string without end-string.
Documentation/security/keys/core.rst:1666: WARNING: Inline emphasis start-string without end-string.Fix it by using a code-block instead.
Signed-off-by: Mauro Carvalho Chehab
Signed-off-by: Jonathan Corbet