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2024-11-25Revert "HID: bpf: allow write access to quirks field in struct hid_device"Linus Torvalds
This reverts commit 6fd47effe92b, and the related self-test update commit e14e0eaeb040 ("selftests/hid: add test for assigning a given device to hid-generic"). It results in things like the scroll wheel on Logitech mice not working after a reboot due to the kernel being confused about the state of the high-resolution mode. Quoting Benjamin Tissoires: "The idea of 6fd47effe92b was to be able to call hid_bpf_rdesc_fixup() once per reprobe of the device. However, because the bpf filter can now change the quirk value, the call had to be moved before the driver gets bound (which was previously ensuring the unicity of the call). The net effect is that now, in the case hid-generic gets loaded first and then the specific driver gets loaded once the disk is available, the value of ->quirks is not reset, but kept to the value that was set by hid-generic (HID_QUIRK_INPUT_PER_APP). Once hid-logitech-hidpp kicks in, that quirk is now set, which creates two inputs for the single mouse: one keyboard for fancy shortcuts, and one mouse node. However, hid-logitech-hidpp expects only one input node to be attached (it stores it into hidpp->input), and when a wheel event is received, because there is some processing with high-resolution wheel events, the wheel event is injected into hidpp->input. And of course, when HID_QUIRK_INPUT_PER_APP is set, hidpp->input gets the keyboard node, which doesn't have wheel event type, and the events are ignored" Reported-and-bisected-by: Mike Galbraith <efault@gmx.de> Link: https://lore.kernel.org/all/CAHk-=wiUkQM3uheit2cNM0Y0OOY5qqspJgC8LkmOkJ2p2LDxcw@mail.gmail.com/ Acked-by: Benjamin Tissoires <bentiss@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-10-04HID: bpf: allow write access to quirks field in struct hid_deviceBenjamin Tissoires
This allows to give more control from BPF during report descriptor fixup. We already reset the quirks before calling ->probe(), so now we reset it once before calling hid_bpf_rdesc_fixup(). Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net> Link: https://patch.msgid.link/20241001-hid-bpf-hid-generic-v3-4-2ef1019468df@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-09-27HID: bpf: fix cfi stubs for hid_bpf_opsBenjamin Tissoires
With the introduction of commit e42ac1418055 ("bpf: Check unsupported ops from the bpf_struct_ops's cfi_stubs"), a HID-BPF struct_ops containing a .hid_hw_request() or a .hid_hw_output_report() was failing to load as the cfi stubs were not defined. Fix that by defining those simple static functions and restore HID-BPF functionality. This was detected with the HID selftests suddenly failing on Linus' tree. Cc: stable@vger.kernel.org # v6.11+ Fixes: 9286675a2aed ("HID: bpf: add HID-BPF hooks for hid_hw_output_report") Fixes: 8bd0488b5ea5 ("HID: bpf: add HID-BPF hooks for hid_hw_raw_requests") Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Signed-off-by: Jiri Kosina <jkosina@suse.com>
2024-07-24HID: bpf: prevent the same struct_ops to be attached more than onceBenjamin Tissoires
If the struct_ops is already attached, we should bail out or we will end up in various locks and pointer issues while unregistering. Link: https://patch.msgid.link/20240723-fix-6-11-bpf-v1-3-b9d770346784@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-07-17Merge tag 'for-linus-2024071601' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid Pull HID updates from Benjamin Tissoires: - rewrite of the HID-BPF internal implementation to use bpf struct_ops instead of a tracing endpoint (Benjamin Tissoires) - add two new HID-BPF hooks to be able to intercept userspace calls targeting a HID device and filtering them (Benjamin Tissoires) - add support for various new devices through HID-BPF filters (Benjamin Tissoires) - add support for the magic keyboard backlight (Orlando Chamberlain) - add the missing MODULE_DESCRIPTION() macros in HID drivers (Jeff Johnson) - use of kvzalloc in case memory gets too fragmented (Hailong Liu) - retrieve the device firmware node in the child HID device (Danny Kaehn) - some hid-uclogic improvements (José Expósito) - some more typos, trivial fixes, kernel doctext and unused functions cleanups * tag 'for-linus-2024071601' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid: (60 commits) HID: hid-steam: Fix typo in goto label HID: mcp2221: Remove unnecessary semicolon HID: Fix spelling mistakes "Kensigton" -> "Kensington" HID: add more missing MODULE_DESCRIPTION() macros HID: samples: fix the 2 struct_ops definitions HID: fix for amples in for-6.11/bpf HID: apple: Add support for magic keyboard backlight on T2 Macs HID: bpf: Thrustmaster TCA Yoke Boeing joystick fix HID: bpf: Add Huion Dial 2 bpf fixup HID: bpf: Add support for the XP-PEN Deco Mini 4 HID: bpf: move the BIT() macro to hid_bpf_helpers.h HID: bpf: add a driver for the Huion Inspiroy 2S (H641P) HID: bpf: Add a HID report composition helper macros HID: bpf: doc fixes for hid_hw_request() hooks HID: bpf: doc fixes for hid_hw_request() hooks HID: bpf: fix gcc warning and unify __u64 into u64 selftests/hid: ensure CKI can compile our new tests on old kernels selftests/hid: add an infinite loop test for hid_bpf_try_input_report selftests/hid: add another test for injecting an event from an event hook HID: bpf: allow hid_device_event hooks to inject input reports on self ...
2024-07-01HID: bpf: fix gcc warning and unify __u64 into u64Benjamin Tissoires
I've got multiple reports of: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]. Let's use the same trick than kernel/bpf/helpers.c to shut up that warning. Even if we were on an architecture with addresses on more than 64 bits, this isn't much of an issue as the address is not used as a pointer, but as an hash and the caller is not supposed to go back to the kernel address ever. And while we change those, make sure we use u64 instead of __u64 for consistency Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202406280633.OPB5uIFj-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202406282304.UydSVncq-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202406282242.Fk738zzy-lkp@intel.com/ Reported-by: Mirsad Todorovac <mtodorovac69@gmail.com> Fixes: 67eccf151d76 ("HID: add source argument to HID low level functions") Link: https://patch.msgid.link/20240701-fix-cki-v2-2-20564e2e1393@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-27HID: bpf: add HID-BPF hooks for hid_hw_output_reportBenjamin Tissoires
Same story than hid_hw_raw_requests: This allows to intercept and prevent or change the behavior of hid_hw_output_report() from a bpf program. The intent is to solve a couple of use case: - firewalling a HID device: a firewall can monitor who opens the hidraw nodes and then prevent or allow access to write operations on that hidraw node. - change the behavior of a device and emulate a new HID feature request The hook is allowed to be run as sleepable so it can itself call hid_hw_output_report(), which allows to "convert" one feature request into another or even call the feature request on a different HID device on the same physical device. Link: https://patch.msgid.link/20240626-hid_hw_req_bpf-v2-7-cfd60fb6c79f@kernel.org Acked-by: Jiri Kosina <jkosina@suse.com> Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-27HID: bpf: add HID-BPF hooks for hid_hw_raw_requestsBenjamin Tissoires
This allows to intercept and prevent or change the behavior of hid_hw_raw_request() from a bpf program. The intent is to solve a couple of use case: - firewalling a HID device: a firewall can monitor who opens the hidraw nodes and then prevent or allow access to write operations on that hidraw node. - change the behavior of a device and emulate a new HID feature request The hook is allowed to be run as sleepable so it can itself call hid_bpf_hw_request(), which allows to "convert" one feature request into another or even call the feature request on a different HID device on the same physical device. Link: https://patch.msgid.link/20240626-hid_hw_req_bpf-v2-4-cfd60fb6c79f@kernel.org Acked-by: Jiri Kosina <jkosina@suse.com> Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-27HID: bpf: protect HID-BPF prog_list access by a SRCUBenjamin Tissoires
We want to add sleepable callbacks for hid_hw_raw_request() and hid_hw_output_report(), but we can not use a plain RCU for those. Prepare for a SRCU so we can extend HID-BPF. This changes a little bit how hid_bpf_device_init() behaves, as it may now fail, so there is a tiny hid-core.c change to accommodate for this. Link: https://patch.msgid.link/20240626-hid_hw_req_bpf-v2-3-cfd60fb6c79f@kernel.org Acked-by: Jiri Kosina <jkosina@suse.com> Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-27HID: add source argument to HID low level functionsBenjamin Tissoires
This allows to know who actually sent what when we process the request to the device. This will be useful for a BPF firewall program to allow or not requests coming from a dedicated hidraw node client. Link: https://patch.msgid.link/20240626-hid_hw_req_bpf-v2-2-cfd60fb6c79f@kernel.org Acked-by: Jiri Kosina <jkosina@suse.com> Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-14HID: bpf: make part of struct hid_device writableBenjamin Tissoires
It is useful to change the name, the phys and/or the uniq of a struct hid_device during .rdesc_fixup(). For example, hid-uclogic.ko changes the uniq to store the firmware version to differentiate between 2 devices sharing the same PID. In the same way, changing the device name is useful when the device export 3 nodes, all with the same name. Link: https://lore.kernel.org/r/20240608-hid_bpf_struct_ops-v3-16-6ac6ade58329@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-14HID: bpf: rework hid_bpf_ops_btf_struct_accessBenjamin Tissoires
The idea is to provide a list of stucts and their editable fields. Currently no functional changes are introduced here, we will add some more writeable fields in the next patch. Acked-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20240608-hid_bpf_struct_ops-v3-15-6ac6ade58329@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-14bpf: allow bpf helpers to be used into HID-BPF struct_opsBenjamin Tissoires
Without this helpers like bpf_printk() or bpf_map_update() are not available, making anything but change of bytes impossible to do. Link: https://lore.kernel.org/r/20240608-hid_bpf_struct_ops-v3-14-6ac6ade58329@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
2024-06-14HID: bpf: implement HID-BPF through bpf_struct_opsBenjamin Tissoires
We do this implementation in several steps to not have the CI failing: - first (this patch), we add struct_ops while keeping the existing infra available - then we change the selftests, the examples and the existing in-tree HID-BPF programs - then we remove the existing trace points making old HID-BPF obsolete There are a few advantages of struct_ops over tracing: - compatibility with sleepable programs (for hid_hw_raw_request() in a later patch) - a lot simpler in the kernel: it's a simple rcu protected list - we can add more parameters to the function called without much trouble - the "attach" is now generic through BPF-core: the caller just needs to set hid_id and flags before calling __load(). - all the BPF tough part is not handled in BPF-core through generic processing - hid_bpf_ctx is now only writable where it needs be Acked-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20240608-hid_bpf_struct_ops-v3-3-6ac6ade58329@kernel.org Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>