Commit graph

13 commits

Author SHA1 Message Date
Fangrui Song
bbaf1ff06a bpf: Replace deprecated -target with --target= for Clang
The -target option has been deprecated since clang 3.4 in 2013. Therefore, use
the preferred --target=bpf form instead. This also matches how we use --target=
in scripts/Makefile.clang.

Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: 274b6f0c87
Link: https://lore.kernel.org/bpf/20230624001856.1903733-1-maskray@google.com
2023-06-29 15:46:17 +02:00
David Vernet
fb2211a57c bpf: Remove now-unnecessary NULL checks for KF_RELEASE kfuncs
Now that we're not invoking kfunc destructors when the kptr in a map was
NULL, we no longer require NULL checks in many of our KF_RELEASE kfuncs.
This patch removes those NULL checks.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230325213144.486885-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-25 16:56:22 -07:00
Linus Torvalds
6c71297eaf for-linus-2023022201
-----BEGIN PGP SIGNATURE-----
 
 iQJSBAABCAA8FiEEoEVH9lhNrxiMPSyI7MXwXhnZSjYFAmP15aoeHGJlbmphbWlu
 LnRpc3NvaXJlc0ByZWRoYXQuY29tAAoJEOzF8F4Z2Uo2nwkP/Rcr5lZYKQ59ezoJ
 PwHx/0wO1Qpgd4fRwD5Mvxynmfoq20A6FZFpmtjUjNcP3dm3X2UJtXE3HkDECCFP
 5daqTFOswFiPFtcMlIl+SHxNgIIlTodbqx9MAFj/7n5aihB54JpTHWsgbENj35Y1
 RLHYDi0+wj69y9ctOkqKGWHp8Uf220RWrD7zZf7AJAc5cwot1kM00RSy9dSAJ0vB
 riZdCQqYwXbf4I1uFzthS6AdIIWcpmpZyYFnsF7F2xQADqCNXr1MTmG0uC+Ey/J/
 0PZXjkyMO/pNwxarRiXmBKnsJJlJajxRXGtpgKYZu8AnIaXuNu/z987Y1pZ/kYis
 OQSKib2bGWzT2MycqiuVVrOChIMvqmk2aPRvg73jojpSySYTKn1Jp/XHyXS8qkkQ
 HJ/u6VPpe42GdfOGM7V9ig+80z/5D5u1XJECoPpxyKHWQ8S7ZlczQjVT+a8nUuBV
 hPTiqAYE9NT6SQJ0b5z2uhBdGRzvAbCZzDCgvjE87zsRmLzFk/fzMdMPZrlADKMJ
 3qu7ey2GYOBNfnDcJmPu5HmK/A9BaPZiZAMakqjGpezZbe+LGBNskXTRwPpNC+Dh
 11pna0ns+vlxeT7nonO0JsYvsKWy0pPcBvhyUEHWsmHgyagRLIsvg01ezB/Ivu0O
 xYj3UPVEGTiwHBt9xnaZcIjRSPSZ
 =cBvC
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-2023022201' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid

Pull HID updates from Benjamin Tissoires:

 - HID-BPF infrastructure: this allows to start using HID-BPF. Note that
   the mechanism to ship HID-BPF program through the kernel tree is
   still not implemented yet (but is planned).

   This should be a no-op for 99% of users. Also we are gaining
   kselftests for the HID tree (Benjamin Tissoires)

 - Some UAF fixes in workers when using uhid (Pietro Borrello & Benjamin
   Tissoires)

 - Constify hid_ll_driver (Thomas Weißschuh)

 - Allow more custom IIO sensors through HID (Philipp Jungkamp)

 - Logitech HID++ fixes for scroll wheel, protocol and debug (Bastien
   Nocera)

 - Some new device support: Steam Deck (Vicki Pfau), UClogic (José
   Expósito), Logitech G923 Xbox Edition steering wheel (Walt Holman),
   EVision keyboards (Philippe Valembois)

 - other assorted code cleanups and fixes

* tag 'for-linus-2023022201' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid: (99 commits)
  HID: mcp-2221: prevent UAF in delayed work
  hid: bigben_probe(): validate report count
  HID: asus: use spinlock to safely schedule workers
  HID: asus: use spinlock to protect concurrent accesses
  HID: bigben: use spinlock to safely schedule workers
  HID: bigben_worker() remove unneeded check on report_field
  HID: bigben: use spinlock to protect concurrent accesses
  HID: logitech-hidpp: Add myself to authors
  HID: logitech-hidpp: Retry commands when device is busy
  HID: logitech-hidpp: Add more debug statements
  HID: Add support for Logitech G923 Xbox Edition steering wheel
  HID: logitech-hidpp: Add Signature M650
  HID: logitech-hidpp: Remove HIDPP_QUIRK_NO_HIDINPUT quirk
  HID: logitech-hidpp: Don't restart communication if not necessary
  HID: logitech-hidpp: Add constants for HID++ 2.0 error codes
  Revert "HID: logitech-hidpp: add a module parameter to keep firmware gestures"
  HID: logitech-hidpp: Hard-code HID++ 1.0 fast scroll support
  HID: i2c-hid: goodix: Add mainboard-vddio-supply
  dt-bindings: HID: i2c-hid: goodix: Add mainboard-vddio-supply
  HID: i2c-hid: goodix: Stop tying the reset line to the regulator
  ...
2023-02-22 11:24:42 -08:00
Benjamin Tissoires
0c2d572828 HID: bpf: reorder BPF registration
Given that our initial BPF program is not using any kfuncs anymore,
we can reorder the initialization to first try to load it and then
register the kfuncs. This has the advantage of not exporting kfuncs
when HID-BPF is not working.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2023-01-18 22:08:38 +01:00
Benjamin Tissoires
bb2c0aeac1 HID: bpf: clean up entrypoint
We don't need to watch for calls on bpf_prog_put_deferred(), so remove
that from the entrypoints.bpf.c file.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2023-01-18 22:08:38 +01:00
Benjamin Tissoires
4b9a3f49f0 HID: bpf: rework how programs are attached and stored in the kernel
Previously, HID-BPF was relying on a bpf tracing program to be notified
when a program was released from userspace. This is error prone, as
LLVM sometimes inline the function and sometimes not.

So instead of messing up with the bpf prog ref count, we can use the
bpf_link concept which actually matches exactly what we want:
- a bpf_link represents the fact that a given program is attached to a
  given HID device
- as long as the bpf_link has fd opened (either by the userspace program
  still being around or by pinning the bpf object in the bpffs), the
  program stays attached to the HID device
- once every user has closed the fd, we get called by
  hid_bpf_link_release() that we no longer have any users, and we can
  disconnect the program to the device in 2 passes: first atomically clear
  the bit saying that the link is active, and then calling release_work in
  a scheduled work item.

This solves entirely the problems of BPF tracing not showing up and is
definitely cleaner.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2023-01-18 22:08:38 +01:00
Benjamin Tissoires
4e0b1b0731 HID: bpf: enforce HID_BPF dependencies
As mentioned in the link below, having JIT and BPF is not enough to
have fentry/fexit/fmod_ret APIs. This resolves the error that
happens on a system without tracing enabled when hid-bpf tries to
load itself.

Link: https://lore.kernel.org/r/CABRcYmKyRchQhabi1Vd9RcMQFCcb=EtWyEbFDFRTc-L-U8WhgA@mail.gmail.com
Fixes: f5c27da4e3 ("HID: initial BPF implementation")
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Florent Revest <revest@chromium.org>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Link: https://lore.kernel.org/r/20221206145936.922196-4-benjamin.tissoires@redhat.com
2022-12-10 10:41:28 +01:00
Benjamin Tissoires
86020156c8 HID: bpf: do not rely on ALLOW_ERROR_INJECTION
Now that we have  aproper non debug API to declare which function is
fmodret, we can rely on it.

Link: https://lore.kernel.org/all/20221121104403.1545f9b5@gandalf.local.home/
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20221206145936.922196-3-benjamin.tissoires@redhat.com
2022-12-07 15:41:36 +01:00
Benjamin Tissoires
ad190df11a HID: bpf: allow to change the report descriptor
Add a new tracepoint hid_bpf_rdesc_fixup() so we can trigger a
report descriptor fixup in the bpf world.

Whenever the program gets attached/detached, the device is reconnected
meaning that userspace will see it disappearing and reappearing with
the new report descriptor.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2022-11-15 16:28:39 +01:00
Benjamin Tissoires
91a7f802d1 HID: bpf: introduce hid_hw_request()
This function can not be called under IRQ, thus it is only available
while in SEC("syscall").
For consistency, this function requires a HID-BPF context to work with,
and so we also provide a helper to create one based on the HID unique
ID.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

--

changes in v12:
- variable dereferenced before check 'ctx'
  |Reported-by: kernel test robot <lkp@intel.com>
  |Reported-by: Dan Carpenter <error27@gmail.com>

no changes in v11

no changes in v10

changes in v9:
- fixed kfunc declaration aaccording to latest upstream changes

no changes in v8

changes in v7:
- hid_bpf_allocate_context: remove unused variable
- ensures buf is not NULL

changes in v6:
- rename parameter size into buf__sz to teach the verifier about
  the actual buffer size used by the call
- remove the allocated data in the user created context, it's not used

new-ish in v5
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2022-11-15 16:28:30 +01:00
Benjamin Tissoires
658ee5a64f HID: bpf: allocate data memory for device_event BPF programs
We need to also be able to change the size of the report.
Reducing it is easy, because we already have the incoming buffer that is
big enough, but extending it is harder.

Pre-allocate a buffer that is big enough to handle all reports of the
device, and use that as the primary buffer for BPF programs.
To be able to change the size of the buffer, we change the device_event
API and request it to return the size of the buffer.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2022-11-15 16:28:29 +01:00
Benjamin Tissoires
0baef37335 HID: bpf jmp table: simplify the logic of cleaning up programs
Kind of a hack, but works for now:

Instead of listening for any close of eBPF program, we now
decrement the refcount when we insert it in our internal
map of fd progs.

This is safe to do because:
- we listen to any call of destructor of programs
- when a program is being destroyed, we disable it by removing
  it from any RCU list used by any HID device (so it will never
  be called)
- we then trigger a job to cleanup the prog fd map, but we overwrite
  the removal of the elements to not do anything on the programs, just
  remove the allocated space

This is better than previously because we can remove the map of known
programs and their usage count. We now rely on the refcount of
bpf, which has greater chances of being accurate.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2022-11-15 16:28:29 +01:00
Benjamin Tissoires
f5c27da4e3 HID: initial BPF implementation
Declare an entry point that can use fmod_ret BPF programs, and
also an API to access and change the incoming data.

A simpler implementation would consist in just calling
hid_bpf_device_event() for any incoming event and let users deal
with the fact that they will be called for any event of any device.

The goal of HID-BPF is to partially replace drivers, so this situation
can be problematic because we might have programs which will step on
each other toes.

For that, we add a new API hid_bpf_attach_prog() that can be called
from a syscall and we manually deal with a jump table in hid-bpf.

Whenever we add a program to the jump table (in other words, when we
attach a program to a HID device), we keep the number of time we added
this program in the jump table so we can release it whenever there are
no other users.

HID devices have an RCU protected list of available programs in the
jump table, and those programs are called one after the other thanks
to bpf_tail_call().

To achieve the detection of users losing their fds on the programs we
attached, we add 2 tracing facilities on bpf_prog_release() (for when
a fd is closed) and bpf_free_inode() (for when a pinned program gets
unpinned).

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2022-11-15 16:28:28 +01:00