Commit Graph

37882 Commits

Author SHA1 Message Date
Lorenzo Bianconi
c2f2cdbeff bpf: introduce BPF_F_XDP_HAS_FRAGS flag in prog_flags loading the ebpf program
Introduce BPF_F_XDP_HAS_FRAGS and the related field in bpf_prog_aux
in order to notify the driver the loaded program support xdp frags.

Acked-by: Toke Hoiland-Jorgensen <toke@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/db2e8075b7032a356003f407d1b0deb99adaa0ed.1642758637.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-21 14:14:01 -08:00
Di Zhu
748cd5729a bpf: support BPF_PROG_QUERY for progs attached to sockmap
Right now there is no way to query whether BPF programs are
attached to a sockmap or not.

we can use the standard interface in libbpf to query, such as:
bpf_prog_query(mapFd, BPF_SK_SKB_STREAM_PARSER, 0, NULL, ...);
the mapFd is the fd of sockmap.

Signed-off-by: Di Zhu <zhudi2@huawei.com>
Acked-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/r/20220119014005.1209-1-zhudi2@huawei.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-20 21:30:58 -08:00
YiFei Zhu
b44123b4a3 bpf: Add cgroup helpers bpf_{get,set}_retval to get/set syscall return value
The helpers continue to use int for retval because all the hooks
are int-returning rather than long-returning. The return value of
bpf_set_retval is int for future-proofing, in case in the future
there may be errors trying to set the retval.

After the previous patch, if a program rejects a syscall by
returning 0, an -EPERM will be generated no matter if the retval
is already set to -err. This patch change it being forced only if
retval is not -err. This is because we want to support, for
example, invoking bpf_set_retval(-EINVAL) and return 0, and have
the syscall return value be -EINVAL not -EPERM.

For BPF_PROG_CGROUP_INET_EGRESS_RUN_ARRAY, the prior behavior is
that, if the return value is NET_XMIT_DROP, the packet is silently
dropped. We preserve this behavior for backward compatibility
reasons, so even if an errno is set, the errno does not return to
caller. However, setting a non-err to retval cannot propagate so
this is not allowed and we return a -EFAULT in that case.

Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/b4013fd5d16bed0b01977c1fafdeae12e1de61fb.1639619851.git.zhuyifei@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-19 12:51:30 -08:00
YiFei Zhu
c4dcfdd406 bpf: Move getsockopt retval to struct bpf_cg_run_ctx
The retval value is moved to struct bpf_cg_run_ctx for ease of access
in different prog types with different context structs layouts. The
helper implementation (to be added in a later patch in the series) can
simply perform a container_of from current->bpf_ctx to retrieve
bpf_cg_run_ctx.

Unfortunately, there is no easy way to access the current task_struct
via the verifier BPF bytecode rewrite, aside from possibly calling a
helper, so a pointer to current task is added to struct bpf_sockopt_kern
so that the rewritten BPF bytecode can access struct bpf_cg_run_ctx with
an indirection.

For backward compatibility, if a getsockopt program rejects a syscall
by returning 0, an -EPERM will be generated, by having the
BPF_PROG_RUN_ARRAY_CG family macros automatically set the retval to
-EPERM. Unlike prior to this patch, this -EPERM will be visible to
ctx->retval for any other hooks down the line in the prog array.

Additionally, the restriction that getsockopt filters can only set
the retval to 0 is removed, considering that certain getsockopt
implementations may return optlen. Filters are now able to set the
value arbitrarily.

Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/73b0325f5c29912ccea7ea57ec1ed4d388fc1d37.1639619851.git.zhuyifei@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-19 12:51:30 -08:00
YiFei Zhu
f10d059661 bpf: Make BPF_PROG_RUN_ARRAY return -err instead of allow boolean
Right now BPF_PROG_RUN_ARRAY and related macros return 1 or 0
for whether the prog array allows or rejects whatever is being
hooked. The caller of these macros then return -EPERM or continue
processing based on thw macro's return value. Unforunately this is
inflexible, since -EPERM is the only err that can be returned.

This patch should be a no-op; it prepares for the next patch. The
returning of the -EPERM is moved to inside the macros, so the outer
functions are directly returning what the macros returned if they
are non-zero.

Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/788abcdca55886d1f43274c918eaa9f792a9f33b.1639619851.git.zhuyifei@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-19 12:51:30 -08:00
Kumar Kartikeya Dwivedi
5c073f26f9 bpf: Add reference tracking support to kfunc
This patch adds verifier support for PTR_TO_BTF_ID return type of kfunc
to be a reference, by reusing acquire_reference_state/release_reference
support for existing in-kernel bpf helpers.

We make use of the three kfunc types:

- BTF_KFUNC_TYPE_ACQUIRE
  Return true if kfunc_btf_id is an acquire kfunc.  This will
  acquire_reference_state for the returned PTR_TO_BTF_ID (this is the
  only allow return value). Note that acquire kfunc must always return a
  PTR_TO_BTF_ID{_OR_NULL}, otherwise the program is rejected.

- BTF_KFUNC_TYPE_RELEASE
  Return true if kfunc_btf_id is a release kfunc.  This will release the
  reference to the passed in PTR_TO_BTF_ID which has a reference state
  (from earlier acquire kfunc).
  The btf_check_func_arg_match returns the regno (of argument register,
  hence > 0) if the kfunc is a release kfunc, and a proper referenced
  PTR_TO_BTF_ID is being passed to it.
  This is similar to how helper call check uses bpf_call_arg_meta to
  store the ref_obj_id that is later used to release the reference.
  Similar to in-kernel helper, we only allow passing one referenced
  PTR_TO_BTF_ID as an argument. It can also be passed in to normal
  kfunc, but in case of release kfunc there must always be one
  PTR_TO_BTF_ID argument that is referenced.

- BTF_KFUNC_TYPE_RET_NULL
  For kfunc returning PTR_TO_BTF_ID, tells if it can be NULL, hence
  force caller to mark the pointer not null (using check) before
  accessing it. Note that taking into account the case fixed by commit
  93c230e3f5 ("bpf: Enforce id generation for all may-be-null register type")
  we assign a non-zero id for mark_ptr_or_null_reg logic. Later, if more
  return types are supported by kfunc, which have a _OR_NULL variant, it
  might be better to move this id generation under a common
  reg_type_may_be_null check, similar to the case in the commit.

Referenced PTR_TO_BTF_ID is currently only limited to kfunc, but can be
extended in the future to other BPF helpers as well.  For now, we can
rely on the btf_struct_ids_match check to ensure we get the pointer to
the expected struct type. In the future, care needs to be taken to avoid
ambiguity for reference PTR_TO_BTF_ID passed to release function, in
case multiple candidates can release same BTF ID.

e.g. there might be two release kfuncs (or kfunc and helper):

foo(struct abc *p);
bar(struct abc *p);

... such that both release a PTR_TO_BTF_ID with btf_id of struct abc. In
this case we would need to track the acquire function corresponding to
the release function to avoid type confusion, and store this information
in the register state so that an incorrect program can be rejected. This
is not a problem right now, hence it is left as an exercise for the
future patch introducing such a case in the kernel.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-6-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 14:26:42 -08:00
Kumar Kartikeya Dwivedi
d583691c47 bpf: Introduce mem, size argument pair support for kfunc
BPF helpers can associate two adjacent arguments together to pass memory
of certain size, using ARG_PTR_TO_MEM and ARG_CONST_SIZE arguments.
Since we don't use bpf_func_proto for kfunc, we need to leverage BTF to
implement similar support.

The ARG_CONST_SIZE processing for helpers is refactored into a common
check_mem_size_reg helper that is shared with kfunc as well. kfunc
ptr_to_mem support follows logic similar to global functions, where
verification is done as if pointer is not null, even when it may be
null.

This leads to a simple to follow rule for writing kfunc: always check
the argument pointer for NULL, except when it is PTR_TO_CTX. Also, the
PTR_TO_CTX case is also only safe when the helper expecting pointer to
program ctx is not exposed to other programs where same struct is not
ctx type. In that case, the type check will fall through to other cases
and would permit passing other types of pointers, possibly NULL at
runtime.

Currently, we require the size argument to be suffixed with "__sz" in
the parameter name. This information is then recorded in kernel BTF and
verified during function argument checking. In the future we can use BTF
tagging instead, and modify the kernel function definitions. This will
be a purely kernel-side change.

This allows us to have some form of backwards compatibility for
structures that are passed in to the kernel function with their size,
and allow variable length structures to be passed in if they are
accompanied by a size parameter.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 14:26:42 -08:00
Kumar Kartikeya Dwivedi
b202d84422 bpf: Remove check_kfunc_call callback and old kfunc BTF ID API
Completely remove the old code for check_kfunc_call to help it work
with modules, and also the callback itself.

The previous commit adds infrastructure to register all sets and put
them in vmlinux or module BTF, and concatenates all related sets
organized by the hook and the type. Once populated, these sets remain
immutable for the lifetime of the struct btf.

Also, since we don't need the 'owner' module anywhere when doing
check_kfunc_call, drop the 'btf_modp' module parameter from
find_kfunc_desc_btf.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 14:26:41 -08:00
Kumar Kartikeya Dwivedi
dee872e124 bpf: Populate kfunc BTF ID sets in struct btf
This patch prepares the kernel to support putting all kinds of kfunc BTF
ID sets in the struct btf itself. The various kernel subsystems will
make register_btf_kfunc_id_set call in the initcalls (for built-in code
and modules).

The 'hook' is one of the many program types, e.g. XDP and TC/SCHED_CLS,
STRUCT_OPS, and 'types' are check (allowed or not), acquire, release,
and ret_null (with PTR_TO_BTF_ID_OR_NULL return type).

A maximum of BTF_KFUNC_SET_MAX_CNT (32) kfunc BTF IDs are permitted in a
set of certain hook and type for vmlinux sets, since they are allocated
on demand, and otherwise set as NULL. Module sets can only be registered
once per hook and type, hence they are directly assigned.

A new btf_kfunc_id_set_contains function is exposed for use in verifier,
this new method is faster than the existing list searching method, and
is also automatic. It also lets other code not care whether the set is
unallocated or not.

Note that module code can only do single register_btf_kfunc_id_set call
per hook. This is why sorting is only done for in-kernel vmlinux sets,
because there might be multiple sets for the same hook and type that
must be concatenated, hence sorting them is required to ensure bsearch
in btf_id_set_contains continues to work correctly.

Next commit will update the kernel users to make use of this
infrastructure.

Finally, add __maybe_unused annotation for BTF ID macros for the
!CONFIG_DEBUG_INFO_BTF case, so that they don't produce warnings during
build time.

The previous patch is also needed to provide synchronization against
initialization for module BTF's kfunc_set_tab introduced here, as
described below:

  The kfunc_set_tab pointer in struct btf is write-once (if we consider
  the registration phase (comprised of multiple register_btf_kfunc_id_set
  calls) as a single operation). In this sense, once it has been fully
  prepared, it isn't modified, only used for lookup (from the verifier
  context).

  For btf_vmlinux, it is initialized fully during the do_initcalls phase,
  which happens fairly early in the boot process, before any processes are
  present. This also eliminates the possibility of bpf_check being called
  at that point, thus relieving us of ensuring any synchronization between
  the registration and lookup function (btf_kfunc_id_set_contains).

  However, the case for module BTF is a bit tricky. The BTF is parsed,
  prepared, and published from the MODULE_STATE_COMING notifier callback.
  After this, the module initcalls are invoked, where our registration
  function will be called to populate the kfunc_set_tab for module BTF.

  At this point, BTF may be available to userspace while its corresponding
  module is still intializing. A BTF fd can then be passed to verifier
  using bpf syscall (e.g. for kfunc call insn).

  Hence, there is a race window where verifier may concurrently try to
  lookup the kfunc_set_tab. To prevent this race, we must ensure the
  operations are serialized, or waiting for the __init functions to
  complete.

  In the earlier registration API, this race was alleviated as verifier
  bpf_check_mod_kfunc_call didn't find the kfunc BTF ID until it was added
  by the registration function (called usually at the end of module __init
  function after all module resources have been initialized). If the
  verifier made the check_kfunc_call before kfunc BTF ID was added to the
  list, it would fail verification (saying call isn't allowed). The
  access to list was protected using a mutex.

  Now, it would still fail verification, but for a different reason
  (returning ENXIO due to the failed btf_try_get_module call in
  add_kfunc_call), because if the __init call is in progress the module
  will be in the middle of MODULE_STATE_COMING -> MODULE_STATE_LIVE
  transition, and the BTF_MODULE_LIVE flag for btf_module instance will
  not be set, so the btf_try_get_module call will fail.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 14:26:41 -08:00
Kumar Kartikeya Dwivedi
18688de203 bpf: Fix UAF due to race between btf_try_get_module and load_module
While working on code to populate kfunc BTF ID sets for module BTF from
its initcall, I noticed that by the time the initcall is invoked, the
module BTF can already be seen by userspace (and the BPF verifier). The
existing btf_try_get_module calls try_module_get which only fails if
mod->state == MODULE_STATE_GOING, i.e. it can increment module reference
when module initcall is happening in parallel.

Currently, BTF parsing happens from MODULE_STATE_COMING notifier
callback. At this point, the module initcalls have not been invoked.
The notifier callback parses and prepares the module BTF, allocates an
ID, which publishes it to userspace, and then adds it to the btf_modules
list allowing the kernel to invoke btf_try_get_module for the BTF.

However, at this point, the module has not been fully initialized (i.e.
its initcalls have not finished). The code in module.c can still fail
and free the module, without caring for other users. However, nothing
stops btf_try_get_module from succeeding between the state transition
from MODULE_STATE_COMING to MODULE_STATE_LIVE.

This leads to a use-after-free issue when BPF program loads
successfully in the state transition, load_module's do_init_module call
fails and frees the module, and BPF program fd on close calls module_put
for the freed module. Future patch has test case to verify we don't
regress in this area in future.

There are multiple points after prepare_coming_module (in load_module)
where failure can occur and module loading can return error. We
illustrate and test for the race using the last point where it can
practically occur (in module __init function).

An illustration of the race:

CPU 0                           CPU 1
			  load_module
			    notifier_call(MODULE_STATE_COMING)
			      btf_parse_module
			      btf_alloc_id	// Published to userspace
			      list_add(&btf_mod->list, btf_modules)
			    mod->init(...)
...				^
bpf_check		        |
check_pseudo_btf_id             |
  btf_try_get_module            |
    returns true                |  ...
...                             |  module __init in progress
return prog_fd                  |  ...
...                             V
			    if (ret < 0)
			      free_module(mod)
			    ...
close(prog_fd)
 ...
 bpf_prog_free_deferred
  module_put(used_btf.mod) // use-after-free

We fix this issue by setting a flag BTF_MODULE_F_LIVE, from the notifier
callback when MODULE_STATE_LIVE state is reached for the module, so that
we return NULL from btf_try_get_module for modules that are not fully
formed. Since try_module_get already checks that module is not in
MODULE_STATE_GOING state, and that is the only transition a live module
can make before being removed from btf_modules list, this is enough to
close the race and prevent the bug.

A later selftest patch crafts the race condition artifically to verify
that it has been fixed, and that verifier fails to load program (with
ENXIO).

Lastly, a couple of comments:

 1. Even if this race didn't exist, it seems more appropriate to only
    access resources (ksyms and kfuncs) of a fully formed module which
    has been initialized completely.

 2. This patch was born out of need for synchronization against module
    initcall for the next patch, so it is needed for correctness even
    without the aforementioned race condition. The BTF resources
    initialized by module initcall are set up once and then only looked
    up, so just waiting until the initcall has finished ensures correct
    behavior.

Fixes: 541c3bad8d ("bpf: Support BPF ksym variables in kernel modules")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220114163953.1455836-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 14:26:41 -08:00
Linus Torvalds
b35b6d4d71 Merge tag 'pm-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
 "The most signigicant change here is the addition of a new cpufreq
  'P-state' driver for AMD processors as a better replacement for the
  venerable acpi-cpufreq driver.

  There are also other cpufreq updates (in the core, intel_pstate, ARM
  drivers), PM core updates (mostly related to adding new macros for
  declaring PM operations which should make the lives of driver
  developers somewhat easier), and a bunch of assorted fixes and
  cleanups.

  Summary:

   - Add new P-state driver for AMD processors (Huang Rui).

   - Fix initialization of min and max frequency QoS requests in the
     cpufreq core (Rafael Wysocki).

   - Fix EPP handling on Alder Lake in intel_pstate (Srinivas
     Pandruvada).

   - Make intel_pstate update cpuinfo.max_freq when notified of HWP
     capabilities changes and drop a redundant function call from that
     driver (Rafael Wysocki).

   - Improve IRQ support in the Qcom cpufreq driver (Ard Biesheuvel,
     Stephen Boyd, Vladimir Zapolskiy).

   - Fix double devm_remap() in the Mediatek cpufreq driver (Hector
     Yuan).

   - Introduce thermal pressure helpers for cpufreq CPU cooling (Lukasz
     Luba).

   - Make cpufreq use default_groups in kobj_type (Greg Kroah-Hartman).

   - Make cpuidle use default_groups in kobj_type (Greg Kroah-Hartman).

   - Fix two comments in cpuidle code (Jason Wang, Yang Li).

   - Allow model-specific normal EPB value to be used in the intel_epb
     sysfs attribute handling code (Srinivas Pandruvada).

   - Simplify locking in pm_runtime_put_suppliers() (Rafael Wysocki).

   - Add safety net to supplier device release in the runtime PM core
     code (Rafael Wysocki).

   - Capture device status before disabling runtime PM for it (Rafael
     Wysocki).

   - Add new macros for declaring PM operations to allow drivers to
     avoid guarding them with CONFIG_PM #ifdefs or __maybe_unused and
     update some drivers to use these macros (Paul Cercueil).

   - Allow ACPI hardware signature to be honoured during restore from
     hibernation (David Woodhouse).

   - Update outdated operating performance points (OPP) documentation
     (Tang Yizhou).

   - Reduce log severity for informative message regarding frequency
     transition failures in devfreq (Tzung-Bi Shih).

   - Add DRAM frequency controller devfreq driver for Allwinner sunXi
     SoCs (Samuel Holland).

   - Add missing COMMON_CLK dependency to sun8i devfreq driver (Arnd
     Bergmann).

   - Add support for new layout of Psys PowerLimit Register on SPR to
     the Intel RAPL power capping driver (Zhang Rui).

   - Fix typo in a comment in idle_inject.c (Jason Wang).

   - Remove unused function definition from the DTPM (Dynamit Thermal
     Power Management) power capping framework (Daniel Lezcano).

   - Reduce DTPM trace verbosity (Daniel Lezcano)"

* tag 'pm-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (53 commits)
  x86, sched: Fix undefined reference to init_freq_invariance_cppc() build error
  cpufreq: amd-pstate: Fix Kconfig dependencies for AMD P-State
  cpufreq: amd-pstate: Fix struct amd_cpudata kernel-doc comment
  cpuidle: use default_groups in kobj_type
  x86: intel_epb: Allow model specific normal EPB value
  MAINTAINERS: Add AMD P-State driver maintainer entry
  Documentation: amd-pstate: Add AMD P-State driver introduction
  cpufreq: amd-pstate: Add AMD P-State performance attributes
  cpufreq: amd-pstate: Add AMD P-State frequencies attributes
  cpufreq: amd-pstate: Add boost mode support for AMD P-State
  cpufreq: amd-pstate: Add trace for AMD P-State module
  cpufreq: amd-pstate: Introduce the support for the processors with shared memory solution
  cpufreq: amd-pstate: Add fast switch function for AMD P-State
  cpufreq: amd-pstate: Introduce a new AMD P-State driver to support future processors
  ACPI: CPPC: Add CPPC enable register function
  ACPI: CPPC: Check present CPUs for determining _CPC is valid
  ACPI: CPPC: Implement support for SystemIO registers
  x86/msr: Add AMD CPPC MSR definitions
  x86/cpufeatures: Add AMD Collaborative Processor Performance Control feature flag
  cpufreq: use default_groups in kobj_type
  ...
2022-01-10 20:34:00 -08:00
Linus Torvalds
8efd0d9c31 Merge tag '5.17-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
 "Core
  ----

   - Defer freeing TCP skbs to the BH handler, whenever possible, or at
     least perform the freeing outside of the socket lock section to
     decrease cross-CPU allocator work and improve latency.

   - Add netdevice refcount tracking to locate sources of netdevice and
     net namespace refcount leaks.

   - Make Tx watchdog less intrusive - avoid pausing Tx and restarting
     all queues from a single CPU removing latency spikes.

   - Various small optimizations throughout the stack from Eric Dumazet.

   - Make netdev->dev_addr[] constant, force modifications to go via
     appropriate helpers to allow us to keep addresses in ordered data
     structures.

   - Replace unix_table_lock with per-hash locks, improving performance
     of bind() calls.

   - Extend skb drop tracepoint with a drop reason.

   - Allow SO_MARK and SO_PRIORITY setsockopt under CAP_NET_RAW.

  BPF
  ---

   - New helpers:
      - bpf_find_vma(), find and inspect VMAs for profiling use cases
      - bpf_loop(), runtime-bounded loop helper trading some execution
        time for much faster (if at all converging) verification
      - bpf_strncmp(), improve performance, avoid compiler flakiness
      - bpf_get_func_arg(), bpf_get_func_ret(), bpf_get_func_arg_cnt()
        for tracing programs, all inlined by the verifier

   - Support BPF relocations (CO-RE) in the kernel loader.

   - Further the support for BTF_TYPE_TAG annotations.

   - Allow access to local storage in sleepable helpers.

   - Convert verifier argument types to a composable form with different
     attributes which can be shared across types (ro, maybe-null).

   - Prepare libbpf for upcoming v1.0 release by cleaning up APIs,
     creating new, extensible ones where missing and deprecating those
     to be removed.

  Protocols
  ---------

   - WiFi (mac80211/cfg80211):
      - notify user space about long "come back in N" AP responses,
        allow it to react to such temporary rejections
      - allow non-standard VHT MCS 10/11 rates
      - use coarse time in airtime fairness code to save CPU cycles

   - Bluetooth:
      - rework of HCI command execution serialization to use a common
        queue and work struct, and improve handling errors reported in
        the middle of a batch of commands
      - rework HCI event handling to use skb_pull_data, avoiding packet
        parsing pitfalls
      - support AOSP Bluetooth Quality Report

   - SMC:
      - support net namespaces, following the RDMA model
      - improve connection establishment latency by pre-clearing buffers
      - introduce TCP ULP for automatic redirection to SMC

   - Multi-Path TCP:
      - support ioctls: SIOCINQ, OUTQ, and OUTQNSD
      - support socket options: IP_TOS, IP_FREEBIND, IP_TRANSPARENT,
        IPV6_FREEBIND, and IPV6_TRANSPARENT, TCP_CORK and TCP_NODELAY
      - support cmsgs: TCP_INQ
      - improvements in the data scheduler (assigning data to subflows)
      - support fastclose option (quick shutdown of the full MPTCP
        connection, similar to TCP RST in regular TCP)

   - MCTP (Management Component Transport) over serial, as defined by
     DMTF spec DSP0253 - "MCTP Serial Transport Binding".

  Driver API
  ----------

   - Support timestamping on bond interfaces in active/passive mode.

   - Introduce generic phylink link mode validation for drivers which
     don't have any quirks and where MAC capability bits fully express
     what's supported. Allow PCS layer to participate in the validation.
     Convert a number of drivers.

   - Add support to set/get size of buffers on the Rx rings and size of
     the tx copybreak buffer via ethtool.

   - Support offloading TC actions as first-class citizens rather than
     only as attributes of filters, improve sharing and device resource
     utilization.

   - WiFi (mac80211/cfg80211):
      - support forwarding offload (ndo_fill_forward_path)
      - support for background radar detection hardware
      - SA Query Procedures offload on the AP side

  New hardware / drivers
  ----------------------

   - tsnep - FPGA based TSN endpoint Ethernet MAC used in PLCs with
     real-time requirements for isochronous communication with protocols
     like OPC UA Pub/Sub.

   - Qualcomm BAM-DMUX WWAN - driver for data channels of modems
     integrated into many older Qualcomm SoCs, e.g. MSM8916 or MSM8974
     (qcom_bam_dmux).

   - Microchip LAN966x multi-port Gigabit AVB/TSN Ethernet Switch driver
     with support for bridging, VLANs and multicast forwarding
     (lan966x).

   - iwlmei driver for co-operating between Intel's WiFi driver and
     Intel's Active Management Technology (AMT) devices.

   - mse102x - Vertexcom MSE102x Homeplug GreenPHY chips

   - Bluetooth:
      - MediaTek MT7921 SDIO devices
      - Foxconn MT7922A
      - Realtek RTL8852AE

  Drivers
  -------

   - Significantly improve performance in the datapaths of: lan78xx,
     ax88179_178a, lantiq_xrx200, bnxt.

   - Intel Ethernet NICs:
      - igb: support PTP/time PEROUT and EXTTS SDP functions on
        82580/i354/i350 adapters
      - ixgbevf: new PF -> VF mailbox API which avoids the risk of
        mailbox corruption with ESXi
      - iavf: support configuration of VLAN features of finer
        granularity, stacked tags and filtering
      - ice: PTP support for new E822 devices with sub-ns precision
      - ice: support firmware activation without reboot

   - Mellanox Ethernet NICs (mlx5):
      - expose control over IRQ coalescing mode (CQE vs EQE) via ethtool
      - support TC forwarding when tunnel encap and decap happen between
        two ports of the same NIC
      - dynamically size and allow disabling various features to save
        resources for running in embedded / SmartNIC scenarios

   - Broadcom Ethernet NICs (bnxt):
      - use page frag allocator to improve Rx performance
      - expose control over IRQ coalescing mode (CQE vs EQE) via ethtool

   - Other Ethernet NICs:
      - amd-xgbe: add Ryzen 6000 (Yellow Carp) Ethernet support

   - Microsoft cloud/virtual NIC (mana):
      - add XDP support (PASS, DROP, TX)

   - Mellanox Ethernet switches (mlxsw):
      - initial support for Spectrum-4 ASICs
      - VxLAN with IPv6 underlay

   - Marvell Ethernet switches (prestera):
      - support flower flow templates
      - add basic IP forwarding support

   - NXP embedded Ethernet switches (ocelot & felix):
      - support Per-Stream Filtering and Policing (PSFP)
      - enable cut-through forwarding between ports by default
      - support FDMA to improve packet Rx/Tx to CPU

   - Other embedded switches:
      - hellcreek: improve trapping management (STP and PTP) packets
      - qca8k: support link aggregation and port mirroring

   - Qualcomm 802.11ax WiFi (ath11k):
      - qca6390, wcn6855: enable 802.11 power save mode in station mode
      - BSS color change support
      - WCN6855 hw2.1 support
      - 11d scan offload support
      - scan MAC address randomization support
      - full monitor mode, only supported on QCN9074
      - qca6390/wcn6855: report signal and tx bitrate
      - qca6390: rfkill support
      - qca6390/wcn6855: regdb.bin support

   - Intel WiFi (iwlwifi):
      - support SAR GEO Offset Mapping (SGOM) and Time-Aware-SAR (TAS)
        in cooperation with the BIOS
      - support for Optimized Connectivity Experience (OCE) scan
      - support firmware API version 68
      - lots of preparatory work for the upcoming Bz device family

   - MediaTek WiFi (mt76):
      - Specific Absorption Rate (SAR) support
      - mt7921: 160 MHz channel support

   - RealTek WiFi (rtw88):
      - Specific Absorption Rate (SAR) support
      - scan offload

   - Other WiFi NICs
      - ath10k: support fetching (pre-)calibration data from nvmem
      - brcmfmac: configure keep-alive packet on suspend
      - wcn36xx: beacon filter support"

* tag '5.17-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2048 commits)
  tcp: tcp_send_challenge_ack delete useless param `skb`
  net/qla3xxx: Remove useless DMA-32 fallback configuration
  rocker: Remove useless DMA-32 fallback configuration
  hinic: Remove useless DMA-32 fallback configuration
  lan743x: Remove useless DMA-32 fallback configuration
  net: enetc: Remove useless DMA-32 fallback configuration
  cxgb4vf: Remove useless DMA-32 fallback configuration
  cxgb4: Remove useless DMA-32 fallback configuration
  cxgb3: Remove useless DMA-32 fallback configuration
  bnx2x: Remove useless DMA-32 fallback configuration
  et131x: Remove useless DMA-32 fallback configuration
  be2net: Remove useless DMA-32 fallback configuration
  vmxnet3: Remove useless DMA-32 fallback configuration
  bna: Simplify DMA setting
  net: alteon: Simplify DMA setting
  myri10ge: Simplify DMA setting
  qlcnic: Simplify DMA setting
  net: allwinner: Fix print format
  page_pool: remove spinlock in page_pool_refill_alloc_cache()
  amt: fix wrong return type of amt_send_membership_update()
  ...
2022-01-10 19:06:09 -08:00
Linus Torvalds
d93aebbd76 Merge branch 'random-5.17-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random
Pull random number generator updates from Jason Donenfeld:
 "These a bit more numerous than usual for the RNG, due to folks
  resubmitting patches that had been pending prior and generally renewed
  interest.

  There are a few categories of patches in here:

   1) Dominik Brodowski and I traded a series back and forth for a some
      weeks that fixed numerous issues related to seeds being provided
      at extremely early boot by the firmware, before other parts of the
      kernel or of the RNG have been initialized, both fixing some
      crashes and addressing correctness around early boot randomness.
      One of these is marked for stable.

   2) I replaced the RNG's usage of SHA-1 with BLAKE2s in the entropy
      extractor, and made the construction a bit safer and more
      standard. This was sort of a long overdue low hanging fruit, as we
      were supposed to have phased out SHA-1 usage quite some time ago
      (even if all we needed here was non-invertibility). Along the way
      it also made extraction 131% faster. This required a bit of
      Kconfig and symbol plumbing to make things work well with the
      crypto libraries, which is one of the reasons why I'm sending you
      this pull early in the cycle.

   3) I got rid of a truly superfluous call to RDRAND in the hot path,
      which resulted in a whopping 370% increase in performance.

   4) Sebastian Andrzej Siewior sent some patches regarding PREEMPT_RT,
      the full series of which wasn't ready yet, but the first two
      preparatory cleanups were good on their own. One of them touches
      files in kernel/irq/, which is the other reason why I'm sending
      you this pull early in the cycle.

   5) Other assorted correctness fixes from Eric Biggers, Jann Horn,
      Mark Brown, Dominik Brodowski, and myself"

* 'random-5.17-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  random: don't reset crng_init_cnt on urandom_read()
  random: avoid superfluous call to RDRAND in CRNG extraction
  random: early initialization of ChaCha constants
  random: use IS_ENABLED(CONFIG_NUMA) instead of ifdefs
  random: harmonize "crng init done" messages
  random: mix bootloader randomness into pool
  random: do not throw away excess input to crng_fast_load
  random: do not re-init if crng_reseed completes before primary init
  random: fix crash on multiple early calls to add_bootloader_randomness()
  random: do not sign extend bytes for rotation when mixing
  random: use BLAKE2s instead of SHA1 in extraction
  lib/crypto: blake2s: include as built-in
  random: fix data race on crng init time
  random: fix data race on crng_node_pool
  irq: remove unused flags argument from __handle_irq_event_percpu()
  random: remove unused irq_flags argument from add_interrupt_randomness()
  random: document add_hwgenerator_randomness() with other input functions
  MAINTAINERS: add git tree for random.c
2022-01-10 11:52:16 -08:00
Linus Torvalds
48a60bdb2b Merge tag 'core_entry_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull thread_info flag accessor helper updates from Borislav Petkov:
 "Add a set of thread_info.flags accessors which snapshot it before
  accesing it in order to prevent any potential data races, and convert
  all users to those new accessors"

* tag 'core_entry_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  powerpc: Snapshot thread flags
  powerpc: Avoid discarding flags in system_call_exception()
  openrisc: Snapshot thread flags
  microblaze: Snapshot thread flags
  arm64: Snapshot thread flags
  ARM: Snapshot thread flags
  alpha: Snapshot thread flags
  sched: Snapshot thread flags
  entry: Snapshot thread flags
  x86: Snapshot thread flags
  thread_info: Add helpers to snapshot thread flags
2022-01-10 11:34:10 -08:00
Linus Torvalds
5ba13c1c4d Merge tag 'core_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull notifier fix from Borislav Petkov:
 "Return an error when a notifier callback has been registered already"

* tag 'core_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  notifier: Return an error when a callback has already been registered
2022-01-10 11:32:57 -08:00
Rafael J. Wysocki
c001a52df4 Merge branches 'pm-cpuidle', 'pm-core' and 'pm-sleep'
Merge cpuidle updates, PM core updates and one hiberation-related
update for 5.17-rc1:

 - Make cpuidle use default_groups in kobj_type (Greg Kroah-Hartman).

 - Fix two comments in cpuidle code (Jason Wang, Yang Li).

 - Simplify locking in pm_runtime_put_suppliers() (Rafael Wysocki).

 - Add safety net to supplier device release in the runtime PM core
   code (Rafael Wysocki).

 - Capture device status before disabling runtime PM for it (Rafael
   Wysocki).

 - Add new macros for declaring PM operations to allow drivers to
   avoid guarding them with CONFIG_PM #ifdefs or __maybe_unused and
   update some drivers to use these macros (Paul Cercueil).

 - Allow ACPI hardware signature to be honoured during restore from
   hibernation (David Woodhouse).

* pm-cpuidle:
  cpuidle: use default_groups in kobj_type
  cpuidle: Fix cpuidle_remove_state_sysfs() kerneldoc comment
  cpuidle: menu: Fix typo in a comment

* pm-core:
  PM: runtime: Simplify locking in pm_runtime_put_suppliers()
  mmc: mxc: Use the new PM macros
  mmc: jz4740: Use the new PM macros
  PM: runtime: Add safety net to supplier device release
  PM: runtime: Capture device status before disabling runtime PM
  PM: core: Add new *_PM_OPS macros, deprecate old ones
  PM: core: Redefine pm_ptr() macro
  r8169: Avoid misuse of pm_ptr() macro

* pm-sleep:
  PM: hibernate: Allow ACPI hardware signature to be honoured
2022-01-10 17:57:13 +01:00
Linus Torvalds
9b9e211360 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:

 - KCSAN enabled for arm64.

 - Additional kselftests to exercise the syscall ABI w.r.t. SVE/FPSIMD.

 - Some more SVE clean-ups and refactoring in preparation for SME
   support (scalable matrix extensions).

 - BTI clean-ups (SYM_FUNC macros etc.)

 - arm64 atomics clean-up and codegen improvements.

 - HWCAPs for FEAT_AFP (alternate floating point behaviour) and
   FEAT_RPRESS (increased precision of reciprocal estimate and
   reciprocal square root estimate).

 - Use SHA3 instructions to speed-up XOR.

 - arm64 unwind code refactoring/unification.

 - Avoid DC (data cache maintenance) instructions when DCZID_EL0.DZP ==
   1 (potentially set by a hypervisor; user-space already does this).

 - Perf updates for arm64: support for CI-700, HiSilicon PCIe PMU,
   Marvell CN10K LLC-TAD PMU, miscellaneous clean-ups.

 - Other fixes and clean-ups; highlights: fix the handling of erratum
   1418040, correct the calculation of the nomap region boundaries,
   introduce io_stop_wc() mapped to the new DGH instruction (data
   gathering hint).

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits)
  arm64: Use correct method to calculate nomap region boundaries
  arm64: Drop outdated links in comments
  arm64: perf: Don't register user access sysctl handler multiple times
  drivers: perf: marvell_cn10k: fix an IS_ERR() vs NULL check
  perf/smmuv3: Fix unused variable warning when CONFIG_OF=n
  arm64: errata: Fix exec handling in erratum 1418040 workaround
  arm64: Unhash early pointer print plus improve comment
  asm-generic: introduce io_stop_wc() and add implementation for ARM64
  arm64: Ensure that the 'bti' macro is defined where linkage.h is included
  arm64: remove __dma_*_area() aliases
  docs/arm64: delete a space from tagged-address-abi
  arm64: Enable KCSAN
  kselftest/arm64: Add pidbench for floating point syscall cases
  arm64/fp: Add comments documenting the usage of state restore functions
  kselftest/arm64: Add a test program to exercise the syscall ABI
  kselftest/arm64: Allow signal tests to trigger from a function
  kselftest/arm64: Parameterise ptrace vector length information
  arm64/sve: Minor clarification of ABI documentation
  arm64/sve: Generalise vector length configuration prctl() for SME
  arm64/sve: Make sysctl interface for SVE reusable by SME
  ...
2022-01-10 08:49:37 -08:00
Linus Torvalds
d1587f7bfe Merge branch 'for-5.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "This contains the cgroup.procs permission check fixes so that they use
  the credentials at the time of open rather than write, which also
  fixes the cgroup namespace lifetime bug"

* 'for-5.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  selftests: cgroup: Test open-time cgroup namespace usage for migration checks
  selftests: cgroup: Test open-time credential usage for migration checks
  selftests: cgroup: Make cg_create() use 0755 for permission instead of 0644
  cgroup: Use open-time cgroup namespace for process migration perm checks
  cgroup: Allocate cgroup_file_ctx for kernfs_open_file->priv
  cgroup: Use open-time credentials for process migraton perm checks
2022-01-07 15:58:06 -08:00
Sebastian Andrzej Siewior
5320eb42de irq: remove unused flags argument from __handle_irq_event_percpu()
The __IRQF_TIMER bit from the flags argument was used in
add_interrupt_randomness() to distinguish the timer interrupt from other
interrupts. This is no longer the case.

Remove the flags argument from __handle_irq_event_percpu().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07 00:25:25 +01:00
Sebastian Andrzej Siewior
703f7066f4 random: remove unused irq_flags argument from add_interrupt_randomness()
Since commit
   ee3e00e9e7 ("random: use registers from interrupted code for CPU's w/o a cycle counter")

the irq_flags argument is no longer used.

Remove unused irq_flags.

Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: linux-hyperv@vger.kernel.org
Cc: x86@kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07 00:25:25 +01:00
Linus Torvalds
b2b436ec02 Merge tag 'trace-v5.16-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
 "Three minor tracing fixes:

   - Fix missing prototypes in sample module for direct functions

   - Fix check of valid buffer in get_trace_buf()

   - Fix annotations of percpu pointers"

* tag 'trace-v5.16-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Tag trace_percpu_buffer as a percpu pointer
  tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()
  ftrace/samples: Add missing prototypes direct functions
2022-01-06 15:00:43 -08:00
Tejun Heo
e574576416 cgroup: Use open-time cgroup namespace for process migration perm checks
cgroup process migration permission checks are performed at write time as
whether a given operation is allowed or not is dependent on the content of
the write - the PID. This currently uses current's cgroup namespace which is
a potential security weakness as it may allow scenarios where a less
privileged process tricks a more privileged one into writing into a fd that
it created.

This patch makes cgroup remember the cgroup namespace at the time of open
and uses it for migration permission checks instad of current's. Note that
this only applies to cgroup2 as cgroup1 doesn't have namespace support.

This also fixes a use-after-free bug on cgroupns reported in

 https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com

Note that backporting this fix also requires the preceding patch.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Reported-by: syzbot+50f5cf33a284ce738b62@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com
Fixes: 5136f6365c ("cgroup: implement "nsdelegate" mount option")
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06 11:02:29 -10:00
Tejun Heo
0d2b5955b3 cgroup: Allocate cgroup_file_ctx for kernfs_open_file->priv
of->priv is currently used by each interface file implementation to store
private information. This patch collects the current two private data usages
into struct cgroup_file_ctx which is allocated and freed by the common path.
This allows generic private data which applies to multiple files, which will
be used to in the following patch.

Note that cgroup_procs iterator is now embedded as procs.iter in the new
cgroup_file_ctx so that it doesn't need to be allocated and freed
separately.

v2: union dropped from cgroup_file_ctx and the procs iterator is embedded in
    cgroup_file_ctx as suggested by Linus.

v3: Michal pointed out that cgroup1's procs pidlist uses of->priv too.
    Converted. Didn't change to embedded allocation as cgroup1 pidlists get
    stored for caching.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
2022-01-06 11:02:29 -10:00
Tejun Heo
1756d7994a cgroup: Use open-time credentials for process migraton perm checks
cgroup process migration permission checks are performed at write time as
whether a given operation is allowed or not is dependent on the content of
the write - the PID. This currently uses current's credentials which is a
potential security weakness as it may allow scenarios where a less
privileged process tricks a more privileged one into writing into a fd that
it created.

This patch makes both cgroup2 and cgroup1 process migration interfaces to
use the credentials saved at the time of open (file->f_cred) instead of
current's.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Fixes: 187fe84067 ("cgroup: require write perm on common ancestor when moving processes on the default hierarchy")
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06 11:02:28 -10:00
Toke Høiland-Jørgensen
d53ad5d8b2 xdp: Move conversion to xdp_frame out of map functions
All map redirect functions except XSK maps convert xdp_buff to xdp_frame
before enqueueing it. So move this conversion of out the map functions
and into xdp_do_redirect(). This removes a bit of duplicated code, but more
importantly it makes it possible to support caller-allocated xdp_frame
structures, which will be added in a subsequent commit.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103150812.87914-5-toke@redhat.com
2022-01-05 19:46:32 -08:00
Naveen N. Rao
f28439db47 tracing: Tag trace_percpu_buffer as a percpu pointer
Tag trace_percpu_buffer as a percpu pointer to resolve warnings
reported by sparse:
  /linux/kernel/trace/trace.c:3218:46: warning: incorrect type in initializer (different address spaces)
  /linux/kernel/trace/trace.c:3218:46:    expected void const [noderef] __percpu *__vpp_verify
  /linux/kernel/trace/trace.c:3218:46:    got struct trace_buffer_struct *
  /linux/kernel/trace/trace.c:3234:9: warning: incorrect type in initializer (different address spaces)
  /linux/kernel/trace/trace.c:3234:9:    expected void const [noderef] __percpu *__vpp_verify
  /linux/kernel/trace/trace.c:3234:9:    got int *

Link: https://lkml.kernel.org/r/ebabd3f23101d89cb75671b68b6f819f5edc830b.1640255304.git.naveen.n.rao@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 07d777fe8c ("tracing: Add percpu buffers for trace_printk()")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-05 18:53:49 -05:00
Naveen N. Rao
823e670f7e tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()
With the new osnoise tracer, we are seeing the below splat:
    Kernel attempted to read user page (c7d880000) - exploit attempt? (uid: 0)
    BUG: Unable to handle kernel data access on read at 0xc7d880000
    Faulting instruction address: 0xc0000000002ffa10
    Oops: Kernel access of bad area, sig: 11 [#1]
    LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
    ...
    NIP [c0000000002ffa10] __trace_array_vprintk.part.0+0x70/0x2f0
    LR [c0000000002ff9fc] __trace_array_vprintk.part.0+0x5c/0x2f0
    Call Trace:
    [c0000008bdd73b80] [c0000000001c49cc] put_prev_task_fair+0x3c/0x60 (unreliable)
    [c0000008bdd73be0] [c000000000301430] trace_array_printk_buf+0x70/0x90
    [c0000008bdd73c00] [c0000000003178b0] trace_sched_switch_callback+0x250/0x290
    [c0000008bdd73c90] [c000000000e70d60] __schedule+0x410/0x710
    [c0000008bdd73d40] [c000000000e710c0] schedule+0x60/0x130
    [c0000008bdd73d70] [c000000000030614] interrupt_exit_user_prepare_main+0x264/0x270
    [c0000008bdd73de0] [c000000000030a70] syscall_exit_prepare+0x150/0x180
    [c0000008bdd73e10] [c00000000000c174] system_call_vectored_common+0xf4/0x278

osnoise tracer on ppc64le is triggering osnoise_taint() for negative
duration in get_int_safe_duration() called from
trace_sched_switch_callback()->thread_exit().

The problem though is that the check for a valid trace_percpu_buffer is
incorrect in get_trace_buf(). The check is being done after calculating
the pointer for the current cpu, rather than on the main percpu pointer.
Fix the check to be against trace_percpu_buffer.

Link: https://lkml.kernel.org/r/a920e4272e0b0635cf20c444707cbce1b2c8973d.1640255304.git.naveen.n.rao@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: e2ace00117 ("tracing: Choose static tp_printk buffer by explicit nesting count")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-05 18:51:25 -05:00
Kris Van Hees
a5bebc4f00 bpf: Fix verifier support for validation of async callbacks
Commit bfc6bb74e4 ("bpf: Implement verifier support for validation of async callbacks.")
added support for BPF_FUNC_timer_set_callback to
the __check_func_call() function.  The test in __check_func_call() is
flaweed because it can mis-interpret a regular BPF-to-BPF pseudo-call
as a BPF_FUNC_timer_set_callback callback call.

Consider the conditional in the code:

	if (insn->code == (BPF_JMP | BPF_CALL) &&
	    insn->imm == BPF_FUNC_timer_set_callback) {

The BPF_FUNC_timer_set_callback has value 170.  This means that if you
have a BPF program that contains a pseudo-call with an instruction delta
of 170, this conditional will be found to be true by the verifier, and
it will interpret the pseudo-call as a callback.  This leads to a mess
with the verification of the program because it makes the wrong
assumptions about the nature of this call.

Solution: include an explicit check to ensure that insn->src_reg == 0.
This ensures that calls cannot be mis-interpreted as an async callback
call.

Fixes: bfc6bb74e4 ("bpf: Implement verifier support for validation of async callbacks.")
Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220105210150.GH1559@oracle.com
2022-01-05 13:38:22 -08:00
Daniel Borkmann
e60b0d12a9 bpf: Don't promote bogus looking registers after null check.
If we ever get to a point again where we convert a bogus looking <ptr>_or_null
typed register containing a non-zero fixed or variable offset, then lets not
reset these bounds to zero since they are not and also don't promote the register
to a <ptr> type, but instead leave it as <ptr>_or_null. Converting to a unknown
register could be an avenue as well, but then if we run into this case it would
allow to leak a kernel pointer this way.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-05 12:00:19 -08:00
Catalin Marinas
945409a6ef Merge branches 'for-next/misc', 'for-next/cache-ops-dzp', 'for-next/stacktrace', 'for-next/xor-neon', 'for-next/kasan', 'for-next/armv8_7-fp', 'for-next/atomics', 'for-next/bti', 'for-next/sve', 'for-next/kselftest' and 'for-next/kcsan', remote-tracking branch 'arm64/for-next/perf' into for-next/core
* arm64/for-next/perf: (32 commits)
  arm64: perf: Don't register user access sysctl handler multiple times
  drivers: perf: marvell_cn10k: fix an IS_ERR() vs NULL check
  perf/smmuv3: Fix unused variable warning when CONFIG_OF=n
  arm64: perf: Support new DT compatibles
  arm64: perf: Simplify registration boilerplate
  arm64: perf: Support Denver and Carmel PMUs
  drivers/perf: hisi: Add driver for HiSilicon PCIe PMU
  docs: perf: Add description for HiSilicon PCIe PMU driver
  dt-bindings: perf: Add YAML schemas for Marvell CN10K LLC-TAD pmu bindings
  drivers: perf: Add LLC-TAD perf counter support
  perf/smmuv3: Synthesize IIDR from CoreSight ID registers
  perf/smmuv3: Add devicetree support
  dt-bindings: Add Arm SMMUv3 PMCG binding
  perf/arm-cmn: Add debugfs topology info
  perf/arm-cmn: Add CI-700 Support
  dt-bindings: perf: arm-cmn: Add CI-700
  perf/arm-cmn: Support new IP features
  perf/arm-cmn: Demarcate CMN-600 specifics
  perf/arm-cmn: Move group validation data off-stack
  perf/arm-cmn: Optimise DTC counter accesses
  ...

* for-next/misc:
  : Miscellaneous patches
  arm64: Use correct method to calculate nomap region boundaries
  arm64: Drop outdated links in comments
  arm64: errata: Fix exec handling in erratum 1418040 workaround
  arm64: Unhash early pointer print plus improve comment
  asm-generic: introduce io_stop_wc() and add implementation for ARM64
  arm64: remove __dma_*_area() aliases
  docs/arm64: delete a space from tagged-address-abi
  arm64/fp: Add comments documenting the usage of state restore functions
  arm64: mm: Use asid feature macro for cheanup
  arm64: mm: Rename asid2idx() to ctxid2asid()
  arm64: kexec: reduce calls to page_address()
  arm64: extable: remove unused ex_handler_t definition
  arm64: entry: Use SDEI event constants
  arm64: Simplify checking for populated DT
  arm64/kvm: Fix bitrotted comment for SVE handling in handle_exit.c

* for-next/cache-ops-dzp:
  : Avoid DC instructions when DCZID_EL0.DZP == 1
  arm64: mte: DC {GVA,GZVA} shouldn't be used when DCZID_EL0.DZP == 1
  arm64: clear_page() shouldn't use DC ZVA when DCZID_EL0.DZP == 1

* for-next/stacktrace:
  : Unify the arm64 unwind code
  arm64: Make some stacktrace functions private
  arm64: Make dump_backtrace() use arch_stack_walk()
  arm64: Make profile_pc() use arch_stack_walk()
  arm64: Make return_address() use arch_stack_walk()
  arm64: Make __get_wchan() use arch_stack_walk()
  arm64: Make perf_callchain_kernel() use arch_stack_walk()
  arm64: Mark __switch_to() as __sched
  arm64: Add comment for stack_info::kr_cur
  arch: Make ARCH_STACKWALK independent of STACKTRACE

* for-next/xor-neon:
  : Use SHA3 instructions to speed up XOR
  arm64/xor: use EOR3 instructions when available

* for-next/kasan:
  : Log potential KASAN shadow aliases
  arm64: mm: log potential KASAN shadow alias
  arm64: mm: use die_kernel_fault() in do_mem_abort()

* for-next/armv8_7-fp:
  : Add HWCAPS for ARMv8.7 FEAT_AFP amd FEAT_RPRES
  arm64: cpufeature: add HWCAP for FEAT_RPRES
  arm64: add ID_AA64ISAR2_EL1 sys register
  arm64: cpufeature: add HWCAP for FEAT_AFP

* for-next/atomics:
  : arm64 atomics clean-ups and codegen improvements
  arm64: atomics: lse: define RETURN ops in terms of FETCH ops
  arm64: atomics: lse: improve constraints for simple ops
  arm64: atomics: lse: define ANDs in terms of ANDNOTs
  arm64: atomics lse: define SUBs in terms of ADDs
  arm64: atomics: format whitespace consistently

* for-next/bti:
  : BTI clean-ups
  arm64: Ensure that the 'bti' macro is defined where linkage.h is included
  arm64: Use BTI C directly and unconditionally
  arm64: Unconditionally override SYM_FUNC macros
  arm64: Add macro version of the BTI instruction
  arm64: ftrace: add missing BTIs
  arm64: kexec: use __pa_symbol(empty_zero_page)
  arm64: update PAC description for kernel

* for-next/sve:
  : SVE code clean-ups and refactoring in prepararation of Scalable Matrix Extensions
  arm64/sve: Minor clarification of ABI documentation
  arm64/sve: Generalise vector length configuration prctl() for SME
  arm64/sve: Make sysctl interface for SVE reusable by SME

* for-next/kselftest:
  : arm64 kselftest additions
  kselftest/arm64: Add pidbench for floating point syscall cases
  kselftest/arm64: Add a test program to exercise the syscall ABI
  kselftest/arm64: Allow signal tests to trigger from a function
  kselftest/arm64: Parameterise ptrace vector length information

* for-next/kcsan:
  : Enable KCSAN for arm64
  arm64: Enable KCSAN
2022-01-05 18:14:32 +00:00
David S. Miller
e63a023489 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-12-30

The following pull-request contains BPF updates for your *net-next* tree.

We've added 72 non-merge commits during the last 20 day(s) which contain
a total of 223 files changed, 3510 insertions(+), 1591 deletions(-).

The main changes are:

1) Automatic setrlimit in libbpf when bpf is memcg's in the kernel, from Andrii.

2) Beautify and de-verbose verifier logs, from Christy.

3) Composable verifier types, from Hao.

4) bpf_strncmp helper, from Hou.

5) bpf.h header dependency cleanup, from Jakub.

6) get_func_[arg|ret|arg_cnt] helpers, from Jiri.

7) Sleepable local storage, from KP.

8) Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support, from Kumar.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-31 14:35:40 +00:00
Leon Huayra
9e6b19a66d bpf: Fix typo in a comment in bpf lpm_trie.
Fix typo in a comment in trie_update_elem().

Signed-off-by: Leon Huayra <hffilwlqm@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211229144422.70339-1-hffilwlqm@gmail.com
2021-12-30 18:42:34 -08:00
Jakub Kicinski
aec53e60e0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
  commit 077cdda764 ("net/mlx5e: TC, Fix memory leak with rules with internal port")
  commit 31108d142f ("net/mlx5: Fix some error handling paths in 'mlx5e_tc_add_fdb_flow()'")
  commit 4390c6edc0 ("net/mlx5: Fix some error handling paths in 'mlx5e_tc_add_fdb_flow()'")
  https://lore.kernel.org/all/20211229065352.30178-1-saeed@kernel.org/

net/smc/smc_wr.c
  commit 49dc9013e3 ("net/smc: Use the bitmap API when applicable")
  commit 349d43127d ("net/smc: fix kernel panic caused by race of smc_sock")
  bitmap_zero()/memset() is removed by the fix

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-30 12:12:12 -08:00
Jakub Kicinski
3b80b73a4b net: Add includes masked by netdevice.h including uapi/bpf.h
Add missing includes unmasked by the subsequent change.

Mostly network drivers missing an include for XDP_PACKET_HEADROOM.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211230012742.770642-2-kuba@kernel.org
2021-12-29 20:03:05 -08:00
KP Singh
0fe4b381a5 bpf: Allow bpf_local_storage to be used by sleepable programs
Other maps like hashmaps are already available to sleepable programs.
Sleepable BPF programs run under trace RCU. Allow task, sk and inode
storage to be used from sleepable programs. This allows sleepable and
non-sleepable programs to provide shareable annotations on kernel
objects.

Sleepable programs run in trace RCU where as non-sleepable programs run
in a normal RCU critical section i.e.  __bpf_prog_enter{_sleepable}
and __bpf_prog_exit{_sleepable}) (rcu_read_lock or rcu_read_lock_trace).

In order to make the local storage maps accessible to both sleepable
and non-sleepable programs, one needs to call both
call_rcu_tasks_trace and call_rcu to wait for both trace and classical
RCU grace periods to expire before freeing memory.

Paul's work on call_rcu_tasks_trace allows us to have per CPU queueing
for call_rcu_tasks_trace. This behaviour can be achieved by setting
rcupdate.rcu_task_enqueue_lim=<num_cpus> boot parameter.

In light of these new performance changes and to keep the local storage
code simple, avoid adding a new flag for sleepable maps / local storage
to select the RCU synchronization (trace / classical).

Also, update the dereferencing of the pointers to use
rcu_derference_check (with either the trace or normal RCU locks held)
with a common bpf_rcu_lock_held helper method.

Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20211224152916.1550677-2-kpsingh@kernel.org
2021-12-29 17:54:40 -08:00
Haimin Zhang
3ccdcee284 bpf: Add missing map_get_next_key method to bloom filter map.
Without it, kernel crashes in map_get_next_key().

Fixes: 9330986c03 ("bpf: Add bloom filter map implementation")
Reported-by: TCS Robot <tcs_robot@tencent.com>
Signed-off-by: Haimin Zhang <tcs_kernel@tencent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Joanne Koong <joannekoong@fb.com>
Link: https://lore.kernel.org/bpf/1640776802-22421-1-git-send-email-tcs.kernel@gmail.com
2021-12-29 09:38:31 -08:00
Jakub Kicinski
b6459415b3 net: Don't include filter.h from net/sock.h
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
2021-12-29 08:48:14 -08:00
Borislav Petkov
5abb065dca notifier: Return an error when a callback has already been registered
Return -EEXIST when a notifier callback has already been registered on a
notifier chain.

This should avoid any homegrown registration tracking at the callsite
like

  https://lore.kernel.org/amd-gfx/20210512013058.6827-1-mukul.joshi@amd.com

for example.

This version is an alternative of

  https://lore.kernel.org/r/20211108101157.15189-1-bp@alien8.de

which needed to touch every caller not checking the registration
routine's return value.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/YcSWNdUBS8A2ZB3s@zn.tnic
2021-12-29 10:37:33 +01:00
Linus Torvalds
d0cc67b278 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "9 patches.

  Subsystems affected by this patch series: mm (kfence, mempolicy,
  memory-failure, pagemap, pagealloc, damon, and memory-failure),
  core-kernel, and MAINTAINERS"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page()
  mm/damon/dbgfs: protect targets destructions with kdamond_lock
  mm/page_alloc: fix __alloc_size attribute for alloc_pages_exact_nid
  mm: delete unsafe BUG from page_cache_add_speculative()
  mm, hwpoison: fix condition in free hugetlb page path
  MAINTAINERS: mark more list instances as moderated
  kernel/crash_core: suppress unknown crashkernel parameter warning
  mm: mempolicy: fix THP allocations escaping mempolicy restrictions
  kfence: fix memory leak when cat kfence objects
2021-12-25 12:30:03 -08:00
Philipp Rudo
71d2bcec2d kernel/crash_core: suppress unknown crashkernel parameter warning
When booting with crashkernel= on the kernel command line a warning
similar to

    Kernel command line: ro console=ttyS0 crashkernel=256M
    Unknown kernel command line parameters "crashkernel=256M", will be passed to user space.

is printed.

This comes from crashkernel= being parsed independent from the kernel
parameter handling mechanism.  So the code in init/main.c doesn't know
that crashkernel= is a valid kernel parameter and prints this incorrect
warning.

Suppress the warning by adding a dummy early_param handler for
crashkernel=.

Link: https://lkml.kernel.org/r/20211208133443.6867-1-prudo@redhat.com
Fixes: 86d1919a4f ("init: print out unknown kernel parameters")
Signed-off-by: Philipp Rudo <prudo@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-12-25 12:20:55 -08:00
Linus Torvalds
7fe2bc1b64 Merge branch 'ucount-rlimit-fixes-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ucount fix from Eric Biederman:
 "This fixes a silly logic bug in the ucount rlimits code, where it was
  comparing against the wrong limit"

* 'ucount-rlimit-fixes-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ucounts: Fix rlimit max values check
2021-12-23 15:27:02 -08:00
Xiu Jianfeng
0dd668d208 bpf: Use struct_size() helper
In an effort to avoid open-coded arithmetic in the kernel, use the
struct_size() helper instead of open-coded calculation.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://github.com/KSPP/linux/issues/160
Link: https://lore.kernel.org/bpf/20211220113048.2859-1-xiujianfeng@huawei.com
2021-12-21 15:35:48 -08:00
Linus Torvalds
e1fe1b10e6 Merge tag 'timers_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Borislav Petkov:

 - Make sure the CLOCK_REALTIME to CLOCK_MONOTONIC offset is never
   positive

* tag 'timers_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Really make sure wall_to_monotonic isn't positive
2021-12-19 12:23:18 -08:00
Linus Torvalds
909e1d166c Merge tag 'locking_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Borislav Petkov:

 - Fix the rtmutex condition checking when the optimistic spinning of a
   waiter needs to be terminated

* tag 'locking_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rtmutex: Fix incorrect condition in rtmutex_spin_on_owner()
2021-12-19 12:17:26 -08:00
Linus Torvalds
c36d891d78 Merge tag 'core_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull signal handlign fix from Borislav Petkov:

 - Prevent lock contention on the new sigaltstack lock on the
   common-case path, when no changes have been made to the alternative
   signal stack.

* tag 'core_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  signal: Skip the altstack update when not needed
2021-12-19 11:46:54 -08:00
Kumar Kartikeya Dwivedi
3363bd0cfb bpf: Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support
Allow passing PTR_TO_CTX, if the kfunc expects a matching struct type,
and punt to PTR_TO_MEM block if reg->type does not fall in one of
PTR_TO_BTF_ID or PTR_TO_SOCK* types. This will be used by future commits
to get access to XDP and TC PTR_TO_CTX, and pass various data (flags,
l4proto, netns_id, etc.) encoded in opts struct passed as pointer to
kfunc.

For PTR_TO_MEM support, arguments are currently limited to pointer to
scalar, or pointer to struct composed of scalars. This is done so that
unsafe scenarios (like passing PTR_TO_MEM where PTR_TO_BTF_ID of
in-kernel valid structure is expected, which may have pointers) are
avoided. Since the argument checking happens basd on argument register
type, it is not easy to ascertain what the expected type is. In the
future, support for PTR_TO_MEM for kfunc can be extended to serve other
usecases. The struct type whose pointer is passed in may have maximum
nesting depth of 4, all recursively composed of scalars or struct with
scalars.

Future commits will add negative tests that check whether these
restrictions imposed for kfunc arguments are duly rejected by BPF
verifier or not.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211217015031.1278167-4-memxor@gmail.com
2021-12-18 18:11:47 -08:00
Hao Luo
216e3cd2f2 bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.
Some helper functions may modify its arguments, for example,
bpf_d_path, bpf_get_stack etc. Previously, their argument types
were marked as ARG_PTR_TO_MEM, which is compatible with read-only
mem types, such as PTR_TO_RDONLY_BUF. Therefore it's legitimate,
but technically incorrect, to modify a read-only memory by passing
it into one of such helper functions.

This patch tags the bpf_args compatible with immutable memory with
MEM_RDONLY flag. The arguments that don't have this flag will be
only compatible with mutable memory types, preventing the helper
from modifying a read-only memory. The bpf_args that have
MEM_RDONLY are compatible with both mutable memory and immutable
memory.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211217003152.48334-9-haoluo@google.com
2021-12-18 13:27:41 -08:00
Hao Luo
34d3a78c68 bpf: Make per_cpu_ptr return rdonly PTR_TO_MEM.
Tag the return type of {per, this}_cpu_ptr with RDONLY_MEM. The
returned value of this pair of helpers is kernel object, which
can not be updated by bpf programs. Previously these two helpers
return PTR_OT_MEM for kernel objects of scalar type, which allows
one to directly modify the memory. Now with RDONLY_MEM tagging,
the verifier will reject programs that write into RDONLY_MEM.

Fixes: 63d9b80dcf ("bpf: Introducte bpf_this_cpu_ptr()")
Fixes: eaa6bcb71e ("bpf: Introduce bpf_per_cpu_ptr()")
Fixes: 4976b718c3 ("bpf: Introduce pseudo_btf_id")
Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211217003152.48334-8-haoluo@google.com
2021-12-18 13:27:41 -08:00
Hao Luo
cf9f2f8d62 bpf: Convert PTR_TO_MEM_OR_NULL to composable types.
Remove PTR_TO_MEM_OR_NULL and replace it with PTR_TO_MEM combined with
flag PTR_MAYBE_NULL.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211217003152.48334-7-haoluo@google.com
2021-12-18 13:27:41 -08:00
Hao Luo
20b2aff4bc bpf: Introduce MEM_RDONLY flag
This patch introduce a flag MEM_RDONLY to tag a reg value
pointing to read-only memory. It makes the following changes:

1. PTR_TO_RDWR_BUF -> PTR_TO_BUF
2. PTR_TO_RDONLY_BUF -> PTR_TO_BUF | MEM_RDONLY

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211217003152.48334-6-haoluo@google.com
2021-12-18 13:27:41 -08:00