diff options
Diffstat (limited to 'Documentation/process')
| -rw-r--r-- | Documentation/process/botching-up-ioctls.rst | 225 | ||||
| -rw-r--r-- | Documentation/process/changes.rst | 14 | ||||
| -rw-r--r-- | Documentation/process/coding-style.rst | 4 | ||||
| -rw-r--r-- | Documentation/process/deprecated.rst | 33 | ||||
| -rw-r--r-- | Documentation/process/email-clients.rst | 20 | ||||
| -rw-r--r-- | Documentation/process/embargoed-hardware-issues.rst | 310 | ||||
| -rw-r--r-- | Documentation/process/howto.rst | 2 | ||||
| -rw-r--r-- | Documentation/process/index.rst | 4 | ||||
| -rw-r--r-- | Documentation/process/magic-number.rst | 1 | ||||
| -rw-r--r-- | Documentation/process/maintainers.rst | 1 | ||||
| -rw-r--r-- | Documentation/process/submitting-patches.rst | 55 |
11 files changed, 637 insertions, 32 deletions
diff --git a/Documentation/process/botching-up-ioctls.rst b/Documentation/process/botching-up-ioctls.rst new file mode 100644 index 000000000000..2d4829b2fb09 --- /dev/null +++ b/Documentation/process/botching-up-ioctls.rst @@ -0,0 +1,225 @@ +================================= +(How to avoid) Botching up ioctls +================================= + +From: http://blog.ffwll.ch/2013/11/botching-up-ioctls.html + +By: Daniel Vetter, Copyright © 2013 Intel Corporation + +One clear insight kernel graphics hackers gained in the past few years is that +trying to come up with a unified interface to manage the execution units and +memory on completely different GPUs is a futile effort. So nowadays every +driver has its own set of ioctls to allocate memory and submit work to the GPU. +Which is nice, since there's no more insanity in the form of fake-generic, but +actually only used once interfaces. But the clear downside is that there's much +more potential to screw things up. + +To avoid repeating all the same mistakes again I've written up some of the +lessons learned while botching the job for the drm/i915 driver. Most of these +only cover technicalities and not the big-picture issues like what the command +submission ioctl exactly should look like. Learning these lessons is probably +something every GPU driver has to do on its own. + + +Prerequisites +------------- + +First the prerequisites. Without these you have already failed, because you +will need to add a 32-bit compat layer: + + * Only use fixed sized integers. To avoid conflicts with typedefs in userspace + the kernel has special types like __u32, __s64. Use them. + + * Align everything to the natural size and use explicit padding. 32-bit + platforms don't necessarily align 64-bit values to 64-bit boundaries, but + 64-bit platforms do. So we always need padding to the natural size to get + this right. + + * Pad the entire struct to a multiple of 64-bits if the structure contains + 64-bit types - the structure size will otherwise differ on 32-bit versus + 64-bit. Having a different structure size hurts when passing arrays of + structures to the kernel, or if the kernel checks the structure size, which + e.g. the drm core does. + + * Pointers are __u64, cast from/to a uintprt_t on the userspace side and + from/to a void __user * in the kernel. Try really hard not to delay this + conversion or worse, fiddle the raw __u64 through your code since that + diminishes the checking tools like sparse can provide. The macro + u64_to_user_ptr can be used in the kernel to avoid warnings about integers + and pointers of different sizes. + + +Basics +------ + +With the joys of writing a compat layer avoided we can take a look at the basic +fumbles. Neglecting these will make backward and forward compatibility a real +pain. And since getting things wrong on the first attempt is guaranteed you +will have a second iteration or at least an extension for any given interface. + + * Have a clear way for userspace to figure out whether your new ioctl or ioctl + extension is supported on a given kernel. If you can't rely on old kernels + rejecting the new flags/modes or ioctls (since doing that was botched in the + past) then you need a driver feature flag or revision number somewhere. + + * Have a plan for extending ioctls with new flags or new fields at the end of + the structure. The drm core checks the passed-in size for each ioctl call + and zero-extends any mismatches between kernel and userspace. That helps, + but isn't a complete solution since newer userspace on older kernels won't + notice that the newly added fields at the end get ignored. So this still + needs a new driver feature flags. + + * Check all unused fields and flags and all the padding for whether it's 0, + and reject the ioctl if that's not the case. Otherwise your nice plan for + future extensions is going right down the gutters since someone will submit + an ioctl struct with random stack garbage in the yet unused parts. Which + then bakes in the ABI that those fields can never be used for anything else + but garbage. This is also the reason why you must explicitly pad all + structures, even if you never use them in an array - the padding the compiler + might insert could contain garbage. + + * Have simple testcases for all of the above. + + +Fun with Error Paths +-------------------- + +Nowadays we don't have any excuse left any more for drm drivers being neat +little root exploits. This means we both need full input validation and solid +error handling paths - GPUs will die eventually in the oddmost corner cases +anyway: + + * The ioctl must check for array overflows. Also it needs to check for + over/underflows and clamping issues of integer values in general. The usual + example is sprite positioning values fed directly into the hardware with the + hardware just having 12 bits or so. Works nicely until some odd display + server doesn't bother with clamping itself and the cursor wraps around the + screen. + + * Have simple testcases for every input validation failure case in your ioctl. + Check that the error code matches your expectations. And finally make sure + that you only test for one single error path in each subtest by submitting + otherwise perfectly valid data. Without this an earlier check might reject + the ioctl already and shadow the codepath you actually want to test, hiding + bugs and regressions. + + * Make all your ioctls restartable. First X really loves signals and second + this will allow you to test 90% of all error handling paths by just + interrupting your main test suite constantly with signals. Thanks to X's + love for signal you'll get an excellent base coverage of all your error + paths pretty much for free for graphics drivers. Also, be consistent with + how you handle ioctl restarting - e.g. drm has a tiny drmIoctl helper in its + userspace library. The i915 driver botched this with the set_tiling ioctl, + now we're stuck forever with some arcane semantics in both the kernel and + userspace. + + * If you can't make a given codepath restartable make a stuck task at least + killable. GPUs just die and your users won't like you more if you hang their + entire box (by means of an unkillable X process). If the state recovery is + still too tricky have a timeout or hangcheck safety net as a last-ditch + effort in case the hardware has gone bananas. + + * Have testcases for the really tricky corner cases in your error recovery code + - it's way too easy to create a deadlock between your hangcheck code and + waiters. + + +Time, Waiting and Missing it +---------------------------- + +GPUs do most everything asynchronously, so we have a need to time operations and +wait for outstanding ones. This is really tricky business; at the moment none of +the ioctls supported by the drm/i915 get this fully right, which means there's +still tons more lessons to learn here. + + * Use CLOCK_MONOTONIC as your reference time, always. It's what alsa, drm and + v4l use by default nowadays. But let userspace know which timestamps are + derived from different clock domains like your main system clock (provided + by the kernel) or some independent hardware counter somewhere else. Clocks + will mismatch if you look close enough, but if performance measuring tools + have this information they can at least compensate. If your userspace can + get at the raw values of some clocks (e.g. through in-command-stream + performance counter sampling instructions) consider exposing those also. + + * Use __s64 seconds plus __u64 nanoseconds to specify time. It's not the most + convenient time specification, but it's mostly the standard. + + * Check that input time values are normalized and reject them if not. Note + that the kernel native struct ktime has a signed integer for both seconds + and nanoseconds, so beware here. + + * For timeouts, use absolute times. If you're a good fellow and made your + ioctl restartable relative timeouts tend to be too coarse and can + indefinitely extend your wait time due to rounding on each restart. + Especially if your reference clock is something really slow like the display + frame counter. With a spec lawyer hat on this isn't a bug since timeouts can + always be extended - but users will surely hate you if their neat animations + starts to stutter due to this. + + * Consider ditching any synchronous wait ioctls with timeouts and just deliver + an asynchronous event on a pollable file descriptor. It fits much better + into event driven applications' main loop. + + * Have testcases for corner-cases, especially whether the return values for + already-completed events, successful waits and timed-out waits are all sane + and suiting to your needs. + + +Leaking Resources, Not +---------------------- + +A full-blown drm driver essentially implements a little OS, but specialized to +the given GPU platforms. This means a driver needs to expose tons of handles +for different objects and other resources to userspace. Doing that right +entails its own little set of pitfalls: + + * Always attach the lifetime of your dynamically created resources to the + lifetime of a file descriptor. Consider using a 1:1 mapping if your resource + needs to be shared across processes - fd-passing over unix domain sockets + also simplifies lifetime management for userspace. + + * Always have O_CLOEXEC support. + + * Ensure that you have sufficient insulation between different clients. By + default pick a private per-fd namespace which forces any sharing to be done + explicitly. Only go with a more global per-device namespace if the objects + are truly device-unique. One counterexample in the drm modeset interfaces is + that the per-device modeset objects like connectors share a namespace with + framebuffer objects, which mostly are not shared at all. A separate + namespace, private by default, for framebuffers would have been more + suitable. + + * Think about uniqueness requirements for userspace handles. E.g. for most drm + drivers it's a userspace bug to submit the same object twice in the same + command submission ioctl. But then if objects are shareable userspace needs + to know whether it has seen an imported object from a different process + already or not. I haven't tried this myself yet due to lack of a new class + of objects, but consider using inode numbers on your shared file descriptors + as unique identifiers - it's how real files are told apart, too. + Unfortunately this requires a full-blown virtual filesystem in the kernel. + + +Last, but not Least +------------------- + +Not every problem needs a new ioctl: + + * Think hard whether you really want a driver-private interface. Of course + it's much quicker to push a driver-private interface than engaging in + lengthy discussions for a more generic solution. And occasionally doing a + private interface to spearhead a new concept is what's required. But in the + end, once the generic interface comes around you'll end up maintainer two + interfaces. Indefinitely. + + * Consider other interfaces than ioctls. A sysfs attribute is much better for + per-device settings, or for child objects with fairly static lifetimes (like + output connectors in drm with all the detection override attributes). Or + maybe only your testsuite needs this interface, and then debugfs with its + disclaimer of not having a stable ABI would be better. + +Finally, the name of the game is to get it right on the first attempt, since if +your driver proves popular and your hardware platforms long-lived then you'll +be stuck with a given ioctl essentially forever. You can try to deprecate +horrible ioctls on newer iterations of your hardware, but generally it takes +years to accomplish this. And then again years until the last user able to +complain about regressions disappears, too. diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst index 2284f2221f02..e47863575917 100644 --- a/Documentation/process/changes.rst +++ b/Documentation/process/changes.rst @@ -383,7 +383,8 @@ Mkinitrd E2fsprogs --------- -- <http://prdownloads.sourceforge.net/e2fsprogs/e2fsprogs-1.29.tar.gz> +- <https://www.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs/> +- <https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git/> JFSutils -------- @@ -393,12 +394,13 @@ JFSutils Reiserfsprogs ------------- -- <http://www.kernel.org/pub/linux/utils/fs/reiserfs/> +- <https://git.kernel.org/pub/scm/linux/kernel/git/jeffm/reiserfsprogs.git/> Xfsprogs -------- -- <ftp://oss.sgi.com/projects/xfs/> +- <https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git> +- <https://www.kernel.org/pub/linux/utils/fs/xfs/xfsprogs/> Pcmciautils ----------- @@ -437,7 +439,9 @@ Networking PPP --- -- <ftp://ftp.samba.org/pub/ppp/> +- <https://download.samba.org/pub/ppp/> +- <https://git.ozlabs.org/?p=ppp.git> +- <https://github.com/paulusmack/ppp/> NFS-utils --------- @@ -447,7 +451,7 @@ NFS-utils Iptables -------- -- <http://www.iptables.org/downloads.html> +- <https://netfilter.org/projects/iptables/index.html> Ip-route2 --------- diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst index f4a2198187f9..edb296c52f61 100644 --- a/Documentation/process/coding-style.rst +++ b/Documentation/process/coding-style.rst @@ -56,7 +56,7 @@ instead of ``double-indenting`` the ``case`` labels. E.g.: case 'K': case 'k': mem <<= 10; - /* fall through */ + fallthrough; default: break; } @@ -988,7 +988,7 @@ Similarly, if you need to calculate the size of some structure member, use .. code-block:: c - #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) + #define sizeof_field(t, f) (sizeof(((t*)0)->f)) There are also min() and max() macros that do strict type checking if you need them. Feel free to peruse that header file to see what else is already diff --git a/Documentation/process/deprecated.rst b/Documentation/process/deprecated.rst index 053b24a6dd38..179f2a5625a0 100644 --- a/Documentation/process/deprecated.rst +++ b/Documentation/process/deprecated.rst @@ -122,14 +122,27 @@ memory adjacent to the stack (when built without `CONFIG_VMAP_STACK=y`) Implicit switch case fall-through --------------------------------- -The C language allows switch cases to "fall through" when -a "break" statement is missing at the end of a case. This, -however, introduces ambiguity in the code, as it's not always -clear if the missing break is intentional or a bug. As there -have been a long list of flaws `due to missing "break" statements +The C language allows switch cases to "fall-through" when a "break" statement +is missing at the end of a case. This, however, introduces ambiguity in the +code, as it's not always clear if the missing break is intentional or a bug. + +As there have been a long list of flaws `due to missing "break" statements <https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow -"implicit fall-through". In order to identify an intentional fall-through -case, we have adopted the marking used by static analyzers: a comment -saying `/* Fall through */`. Once the C++17 `__attribute__((fallthrough))` -is more widely handled by C compilers, static analyzers, and IDEs, we can -switch to using that instead. +"implicit fall-through". + +In order to identify intentional fall-through cases, we have adopted a +pseudo-keyword macro 'fallthrough' which expands to gcc's extension +__attribute__((__fallthrough__)). `Statement Attributes +<https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_ + +When the C17/C18 [[fallthrough]] syntax is more commonly supported by +C compilers, static analyzers, and IDEs, we can switch to using that syntax +for the macro pseudo-keyword. + +All switch/case blocks must end in one of: + + break; + fallthrough; + continue; + goto <label>; + return [expression]; diff --git a/Documentation/process/email-clients.rst b/Documentation/process/email-clients.rst index 07faa5457bcb..5273d06c8ff6 100644 --- a/Documentation/process/email-clients.rst +++ b/Documentation/process/email-clients.rst @@ -40,7 +40,7 @@ Emailed patches should be in ASCII or UTF-8 encoding only. If you configure your email client to send emails with UTF-8 encoding, you avoid some possible charset problems. -Email clients should generate and maintain References: or In-Reply-To: +Email clients should generate and maintain "References:" or "In-Reply-To:" headers so that mail threading is not broken. Copy-and-paste (or cut-and-paste) usually does not work for patches @@ -89,7 +89,7 @@ Claws Mail (GUI) Works. Some people use this successfully for patches. -To insert a patch use :menuselection:`Message-->Insert` File (:kbd:`CTRL-I`) +To insert a patch use :menuselection:`Message-->Insert File` (:kbd:`CTRL-I`) or an external editor. If the inserted patch has to be edited in the Claws composition window @@ -132,8 +132,8 @@ wrapping. At the bottom of your email, put the commonly-used patch delimiter before inserting your patch: three hyphens (``---``). -Then from the :menuselection:`Message` menu item, select insert file and -choose your patch. +Then from the :menuselection:`Message` menu item, select +:menuselection:`insert file` and choose your patch. As an added bonus you can customise the message creation toolbar menu and put the :menuselection:`insert file` icon there. @@ -149,18 +149,16 @@ patches so do not GPG sign them. Signing patches that have been inserted as inlined text will make them tricky to extract from their 7-bit encoding. If you absolutely must send patches as attachments instead of inlining -them as text, right click on the attachment and select properties, and -highlight :menuselection:`Suggest automatic display` to make the attachment +them as text, right click on the attachment and select :menuselection:`properties`, +and highlight :menuselection:`Suggest automatic display` to make the attachment inlined to make it more viewable. When saving patches that are sent as inlined text, select the email that contains the patch from the message list pane, right click and select :menuselection:`save as`. You can use the whole email unmodified as a patch -if it was properly composed. There is no option currently to save the email -when you are actually viewing it in its own window -- there has been a request -filed at kmail's bugzilla and hopefully this will be addressed. Emails are -saved as read-write for user only so you will have to chmod them to make them -group and world readable if you copy them elsewhere. +if it was properly composed. Emails are saved as read-write for user only so +you will have to chmod them to make them group and world readable if you copy +them elsewhere. Lotus Notes (GUI) ***************** diff --git a/Documentation/process/embargoed-hardware-issues.rst b/Documentation/process/embargoed-hardware-issues.rst new file mode 100644 index 000000000000..33edae654599 --- /dev/null +++ b/Documentation/process/embargoed-hardware-issues.rst @@ -0,0 +1,310 @@ +.. _embargoed_hardware_issues: + +Embargoed hardware issues +========================= + +Scope +----- + +Hardware issues which result in security problems are a different category +of security bugs than pure software bugs which only affect the Linux +kernel. + +Hardware issues like Meltdown, Spectre, L1TF etc. must be treated +differently because they usually affect all Operating Systems ("OS") and +therefore need coordination across different OS vendors, distributions, +hardware vendors and other parties. For some of the issues, software +mitigations can depend on microcode or firmware updates, which need further +coordination. + +.. _Contact: + +Contact +------- + +The Linux kernel hardware security team is separate from the regular Linux +kernel security team. + +The team only handles the coordination of embargoed hardware security +issues. Reports of pure software security bugs in the Linux kernel are not +handled by this team and the reporter will be guided to contact the regular +Linux kernel security team (:ref:`Documentation/admin-guide/ +<securitybugs>`) instead. + +The team can be contacted by email at <hardware-security@kernel.org>. This +is a private list of security officers who will help you to coordinate an +issue according to our documented process. + +The list is encrypted and email to the list can be sent by either PGP or +S/MIME encrypted and must be signed with the reporter's PGP key or S/MIME +certificate. The list's PGP key and S/MIME certificate are available from +the following URLs: + + - PGP: https://www.kernel.org/static/files/hardware-security.asc + - S/MIME: https://www.kernel.org/static/files/hardware-security.crt + +While hardware security issues are often handled by the affected hardware +vendor, we welcome contact from researchers or individuals who have +identified a potential hardware flaw. + +Hardware security officers +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The current team of hardware security officers: + + - Linus Torvalds (Linux Foundation Fellow) + - Greg Kroah-Hartman (Linux Foundation Fellow) + - Thomas Gleixner (Linux Foundation Fellow) + +Operation of mailing-lists +^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The encrypted mailing-lists which are used in our process are hosted on +Linux Foundation's IT infrastructure. By providing this service, members +of Linux Foundation's IT operations personnel technically have the +ability to access the embargoed information, but are obliged to +confidentiality by their employment contract. Linux Foundation IT +personnel are also responsible for operating and managing the rest of +kernel.org infrastructure. + +The Linux Foundation's current director of IT Project infrastructure is +Konstantin Ryabitsev. + + +Non-disclosure agreements +------------------------- + +The Linux kernel hardware security team is not a formal body and therefore +unable to enter into any non-disclosure agreements. The kernel community +is aware of the sensitive nature of such issues and offers a Memorandum of +Understanding instead. + + +Memorandum of Understanding +--------------------------- + +The Linux kernel community has a deep understanding of the requirement to +keep hardware security issues under embargo for coordination between +different OS vendors, distributors, hardware vendors and other parties. + +The Linux kernel community has successfully handled hardware security +issues in the past and has the necessary mechanisms in place to allow +community compliant development under embargo restrictions. + +The Linux kernel community has a dedicated hardware security team for +initial contact, which oversees the process of handling such issues under +embargo rules. + +The hardware security team identifies the developers (domain experts) who +will form the initial response team for a particular issue. The initial +response team can bring in further developers (domain experts) to address +the issue in the best technical way. + +All involved developers pledge to adhere to the embargo rules and to keep +the received information confidential. Violation of the pledge will lead to +immediate exclusion from the current issue and removal from all related +mailing-lists. In addition, the hardware security team will also exclude +the offender from future issues. The impact of this consequence is a highly +effective deterrent in our community. In case a violation happens the +hardware security team will inform the involved parties immediately. If you +or anyone becomes aware of a potential violation, please report it +immediately to the Hardware security officers. + + +Process +^^^^^^^ + +Due to the globally distributed nature of Linux kernel development, +face-to-face meetings are almost impossible to address hardware security +issues. Phone conferences are hard to coordinate due to time zones and +other factors and should be only used when absolutely necessary. Encrypted +email has been proven to be the most effective and secure communication +method for these types of issues. + +Start of Disclosure +""""""""""""""""""" + +Disclosure starts by contacting the Linux kernel hardware security team by +email. This initial contact should contain a description of the problem and +a list of any known affected hardware. If your organization builds or +distributes the affected hardware, we encourage you to also consider what +other hardware could be affected. + +The hardware security team will provide an incident-specific encrypted +mailing-list which will be used for initial discussion with the reporter, +further disclosure and coordination. + +The hardware security team will provide the disclosing party a list of +developers (domain experts) who should be informed initially about the +issue after confirming with the developers that they will adhere to this +Memorandum of Understanding and the documented process. These developers +form the initial response team and will be responsible for handling the +issue after initial contact. The hardware security team is supporting the +response team, but is not necessarily involved in the mitigation +development process. + +While individual developers might be covered by a non-disclosure agreement +via their employer, they cannot enter individual non-disclosure agreements +in their role as Linux kernel developers. They will, however, agree to +adhere to this documented process and the Memorandum of Understanding. + +The disclosing party should provide a list of contacts for all other +entities who have already been, or should be, informed about the issue. +This serves several purposes: + + - The list of disclosed entities allows communication accross the + industry, e.g. other OS vendors, HW vendors, etc. + + - The disclosed entities can be contacted to name experts who should + participate in the mitigation development. + + - If an expert which is required to handle an issue is employed by an + listed entity or member of an listed entity, then the response teams can + request the disclosure of that expert from that entity. This ensures + that the expert is also part of the entity's response team. + +Disclosure +"""""""""" + +The disclosing party provides detailed information to the initial response +team via the specific encrypted mailing-list. + +From our experience the technical documentation of these issues is usually +a sufficient starting point and further technical clarification is best +done via email. + +Mitigation development +"""""""""""""""""""""" + +The initial response team sets up an encrypted mailing-list or repurposes +an existing one if appropriate. + +Using a mailing-list is close to the normal Linux development process and +has been successfully used in developing mitigations for various hardware +security issues in the past. + +The mailing-list operates in the same way as normal Linux development. +Patches are posted, discussed and reviewed and if agreed on applied to a +non-public git repository which is only accessible to the participating +developers via a secure connection. The repository contains the main +development branch against the mainline kernel and backport branches for +stable kernel versions as necessary. + +The initial response team will identify further experts from the Linux +kernel developer community as needed. Bringing in experts can happen at any +time of the development process and needs to be handled in a timely manner. + +If an expert is employed by or member of an entity on the disclosure list +provided by the disclosing party, then participation will be requested from +the relevant entity. + +If not, then the disclosing party will be informed about the experts +participation. The experts are covered by the Memorandum of Understanding +and the disclosing party is requested to acknowledge the participation. In +case that the disclosing party has a compelling reason to object, then this +objection has to be raised within five work days and resolved with the +incident team immediately. If the disclosing party does not react within +five work days this is taken as silent acknowledgement. + +After acknowledgement or resolution of an objection the expert is disclosed +by the incident team and brought into the development process. + + +Coordinated release +""""""""""""""""""" + +The involved parties will negotiate the date and time where the embargo +ends. At that point the prepared mitigations are integrated into the +relevant kernel trees and published. + +While we understand that hardware security issues need coordinated embargo +time, the embargo time should be constrained to the minimum time which is +required for all involved parties to develop, test and prepare the +mitigations. Extending embargo time artificially to meet conference talk +dates or other non-technical reasons is creating more work and burden for +the involved developers and response teams as the patches need to be kept +up to date in order to follow the ongoing upstream kernel development, +which might create conflicting changes. + +CVE assignment +"""""""""""""" + +Neither the hardware security team nor the initial response team assign +CVEs, nor are CVEs required for the development process. If CVEs are +provided by the disclosing party they can be used for documentation +purposes. + +Process ambassadors +------------------- + +For assistance with this process we have established ambassadors in various +organizations, who can answer questions about or provide guidance on the +reporting process and further handling. Ambassadors are not involved in the +disclosure of a particular issue, unless requested by a response team or by +an involved disclosed party. The current ambassadors list: + + ============= ======================================================== + ARM + AMD Tom Lendacky <tom.lendacky@amd.com> + IBM + Intel Tony Luck <tony.luck@intel.com> + Qualcomm Trilok Soni <tsoni@codeaurora.org> + + Microsoft Sasha Levin <sashal@kernel.org> + VMware + Xen Andrew Cooper <andrew.cooper3@citrix.com> + + Canonical Tyler Hicks <tyhicks@canonical.com> + Debian Ben Hutchings <ben@decadent.org.uk> + Oracle Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> + Red Hat Josh Poimboeuf <jpoimboe@redhat.com> + SUSE Jiri Kosina <jkosina@suse.cz> + + Amazon Peter Bowen <pzb@amzn.com> + Google Kees Cook <keescook@chromium.org> + ============= ======================================================== + +If you want your organization to be added to the ambassadors list, please +contact the hardware security team. The nominated ambassador has to +understand and support our process fully and is ideally well connected in +the Linux kernel community. + +Encrypted mailing-lists +----------------------- + +We use encrypted mailing-lists for communication. The operating principle +of these lists is that email sent to the list is encrypted either with the +list's PGP key or with the list's S/MIME certificate. The mailing-list +software decrypts the email and re-encrypts it individually for each +subscriber with the subscriber's PGP key or S/MIME certificate. Details +about the mailing-list software and the setup which is used to ensure the +security of the lists and protection of the data can be found here: +https://korg.wiki.kernel.org/userdoc/remail. + +List keys +^^^^^^^^^ + +For initial contact see :ref:`Contact`. For incident specific mailing-lists +the key and S/MIME certificate are conveyed to the subscribers by email +sent from the specific list. + +Subscription to incident specific lists +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Subscription is handled by the response teams. Disclosed parties who want +to participate in the communication send a list of potential subscribers to +the response team so the response team can validate subscription requests. + +Each subscriber needs to send a subscription request to the response team +by email. The email must be signed with the subscriber's PGP key or S/MIME +certificate. If a PGP key is used, it must be available from a public key +server and is ideally connected to the Linux kernel's PGP web of trust. See +also: https://www.kernel.org/signature.html. + +The response team verifies that the subscriber request is valid and adds +the subscriber to the list. After subscription the subscriber will receive +email from the mailing-list which is signed either with the list's PGP key +or the list's S/MIME certificate. The subscriber's email client can extract +the PGP key or the S/MIME certificate from the signature so the subscriber +can send encrypted email to the list. + diff --git a/Documentation/process/howto.rst b/Documentation/process/howto.rst index 6ab75c11d2c3..b6f5a379ad6c 100644 --- a/Documentation/process/howto.rst +++ b/Documentation/process/howto.rst @@ -123,7 +123,7 @@ required reading: https://www.ozlabs.org/~akpm/stuff/tpp.txt "Linux kernel patch submission format" - http://linux.yyz.us/patch-format.html + https://web.archive.org/web/20180829112450/http://linux.yyz.us/patch-format.html :ref:`Documentation/process/stable-api-nonsense.rst <stable_api_nonsense>` This file describes the rationale behind the conscious decision to diff --git a/Documentation/process/index.rst b/Documentation/process/index.rst index 878ebfda7eef..6399d92f0b21 100644 --- a/Documentation/process/index.rst +++ b/Documentation/process/index.rst @@ -45,6 +45,8 @@ Other guides to the community that are of interest to most developers are: submit-checklist kernel-docs deprecated + embargoed-hardware-issues + maintainers These are some overall technical guides that have been put here for now for lack of a better place. @@ -56,7 +58,9 @@ lack of a better place. adding-syscalls magic-number volatile-considered-harmful + botching-up-ioctls clang-format + ../riscv/patch-acceptance .. only:: subproject and html diff --git a/Documentation/process/magic-number.rst b/Documentation/process/magic-number.rst index 547bbf28e615..eee9b44553b3 100644 --- a/Documentation/process/magic-number.rst +++ b/Documentation/process/magic-number.rst @@ -81,7 +81,6 @@ FF_MAGIC 0x4646 fc_info ``drivers/net/ip ISICOM_MAGIC 0x4d54 isi_port ``include/linux/isicom.h`` PTY_MAGIC 0x5001 ``drivers/char/pty.c`` PPP_MAGIC 0x5002 ppp ``include/linux/if_pppvar.h`` -SERIAL_MAGIC 0x5301 async_struct ``include/linux/serial.h`` SSTATE_MAGIC 0x5302 serial_state ``include/linux/serial.h`` SLIP_MAGIC 0x5302 slip ``drivers/net/slip.h`` STRIP_MAGIC 0x5303 strip ``drivers/net/strip.c`` diff --git a/Documentation/process/maintainers.rst b/Documentation/process/maintainers.rst new file mode 100644 index 000000000000..6174cfb4138f --- /dev/null +++ b/Documentation/process/maintainers.rst @@ -0,0 +1 @@ +.. maintainers-include:: diff --git a/Documentation/process/submitting-patches.rst b/Documentation/process/submitting-patches.rst index 9c4299293c72..ba5e944c7a63 100644 --- a/Documentation/process/submitting-patches.rst +++ b/Documentation/process/submitting-patches.rst @@ -782,7 +782,58 @@ helpful, you can use the https://lkml.kernel.org/ redirector (e.g., in the cover email text) to link to an earlier version of the patch series. -16) Sending ``git pull`` requests +16) Providing base tree information +----------------------------------- + +When other developers receive your patches and start the review process, +it is often useful for them to know where in the tree history they +should place your work. This is particularly useful for automated CI +processes that attempt to run a series of tests in order to establish +the quality of your submission before the maintainer starts the review. + +If you are using ``git format-patch`` to generate your patches, you can +automatically include the base tree information in your submission by +using the ``--base`` flag. The easiest and most convenient way to use +this option is with topical branches:: + + $ git checkout -t -b my-topical-branch master + Branch 'my-topical-branch' set up to track local branch 'master'. + Switched to a new branch 'my-topical-branch' + + [perform your edits and commits] + + $ git format-patch --base=auto --cover-letter -o outgoing/ master + outgoing/0000-cover-letter.patch + outgoing/0001-First-Commit.patch + outgoing/... + +When you open ``outgoing/0000-cover-letter.patch`` for editing, you will +notice that it will have the ``base-commit:`` trailer at the very +bottom, which provides the reviewer and the CI tools enough information +to properly perform ``git am`` without worrying about conflicts:: + + $ git checkout -b patch-review [base-commit-id] + Switched to a new branch 'patch-review' + $ git am patches.mbox + Applying: First Commit + Applying: ... + +Please see ``man git-format-patch`` for more information about this +option. + +.. note:: + + The ``--base`` feature was introduced in git version 2.9.0. + +If you are not using git to format your patches, you can still include +the same ``base-commit`` trailer to indicate the commit hash of the tree +on which your work is based. You should add it either in the cover +letter or in the first patch of the series and it should be placed +either below the ``---`` line or at the very bottom of all other +content, right before your email signature. + + +17) Sending ``git pull`` requests --------------------------------- If you have a series of patches, it may be most convenient to have the @@ -844,7 +895,7 @@ Andrew Morton, "The perfect patch" (tpp). <http://www.ozlabs.org/~akpm/stuff/tpp.txt> Jeff Garzik, "Linux kernel patch submission format". - <http://linux.yyz.us/patch-format.html> + <https://web.archive.org/web/20180829112450/http://linux.yyz.us/patch-format.html> Greg Kroah-Hartman, "How to piss off a kernel subsystem maintainer". <http://www.kroah.com/log/linux/maintainer.html> |
