[RFC,HID,5/7] WIP: add HID-BPF hooks for hid_hw_raw_requests

Message ID	20240508-hid_bpf_async_fun-v1-5-558375a25657@kernel.org (mailing list archive)
State	RFC
Headers	show Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C5A027E0E8; Wed, 8 May 2024 10:27:19 +0000 (UTC) From: Benjamin Tissoires <bentiss@kernel.org> Date: Wed, 08 May 2024 12:26:40 +0200 Subject: [PATCH RFC HID 5/7] WIP: add HID-BPF hooks for hid_hw_raw_requests Precedence: bulk MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20240508-hid_bpf_async_fun-v1-5-558375a25657@kernel.org> References: <20240508-hid_bpf_async_fun-v1-0-558375a25657@kernel.org> In-Reply-To: <20240508-hid_bpf_async_fun-v1-0-558375a25657@kernel.org> To: Benjamin Tissoires <benjamin.tissoires@redhat.com> Cc: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, bpf@vger.kernel.org, Benjamin Tissoires <bentiss@kernel.org>
Series	Use the new __s_async for HID-BPF \| expand [RFC,HID,0/7] Use the new __s_async for HID-BPF [RFC,HID,1/7] HID: bpf: change the prog run logic [RFC,HID,2/7] selftests/hid: fix bpf programs for the new attachment logic [RFC,HID,3/7] HID: bpf: allow for sleepable bpf hooks [RFC,HID,4/7] HID: add source argument to HID low level functions [RFC,HID,5/7] WIP: add HID-BPF hooks for hid_hw_raw_requests [RFC,HID,6/7] WIP: selftests/hid: add tests for hid_hw_raw_request HID-BPF hooks [RFC,HID,7/7] HID: bpf: prevent infinite recursions with hid_hw_raw_requests hooks

Context	Check	Description
netdev/tree_selection	success	Not a local patch

diff --git a/drivers/hid/bpf/hid_bpf_dispatch.c b/drivers/hid/bpf/hid_bpf_dispatch.c index 55c9e74c2465..7aeab3f9f2c7 100644 --- a/drivers/hid/bpf/hid_bpf_dispatch.c +++ b/drivers/hid/bpf/hid_bpf_dispatch.c @@ -45,6 +45,11 @@ __weak noinline int hid_bpf_device_event(struct hid_bpf_ctx *ctx) return 0; } +__weak noinline int hid_bpf_raw_request(struct hid_bpf_ctx *ctx) +{ + return 0; +} + u8 * dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type, u8 *data, u32 *size, int interrupt, u64 source) @@ -71,6 +76,9 @@ dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type memset(ctx_kern.data, 0, hdev->bpf.allocated_data); memcpy(ctx_kern.data, data, *size); + if (*size) + ctx_kern.ctx.reportnum = data[0]; + ret = hid_bpf_prog_run(hdev, HID_BPF_PROG_TYPE_DEVICE_EVENT, &ctx_kern, false); if (ret < 0) return ERR_PTR(ret); @@ -86,6 +94,49 @@ dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type } EXPORT_SYMBOL_GPL(dispatch_hid_bpf_device_event); +u8 * +dispatch_hid_bpf_raw_requests(struct hid_device *hdev, + unsigned char reportnum, u8 *buf, + u32 *size, enum hid_report_type rtype, + enum hid_class_request reqtype, + u64 source) +{ + struct hid_bpf_ctx_kern ctx_kern = { + .ctx = { + .hid = hdev, + .report_type = rtype, + .reqtype = reqtype, + .allocated_size = *size, + .size = *size, + .source = source, + .reportnum = reportnum, + }, + .data = buf, + }; + int ret; + + if (rtype >= HID_REPORT_TYPES) + return ERR_PTR(-EINVAL); + + /* no program has been attached yet */ + // if (!hdev->bpf.device_data) + // return buf; + + ret = hid_bpf_prog_run(hdev, HID_BPF_PROG_TYPE_RAW_REQUEST, &ctx_kern, true); + if (ret < 0) + return ERR_PTR(ret); + + if (ret) { + if (ret > ctx_kern.ctx.allocated_size) + return ERR_PTR(-EINVAL); + + *size = ret; + } + + return ctx_kern.data; +} +EXPORT_SYMBOL_GPL(dispatch_hid_bpf_raw_requests); + /** * hid_bpf_rdesc_fixup - Called when the probe function parses the report * descriptor of the HID device diff --git a/drivers/hid/bpf/hid_bpf_jmp_table.c b/drivers/hid/bpf/hid_bpf_jmp_table.c index 4cceff354962..e183dc2835c7 100644 --- a/drivers/hid/bpf/hid_bpf_jmp_table.c +++ b/drivers/hid/bpf/hid_bpf_jmp_table.c @@ -64,6 +64,7 @@ static int hid_bpf_max_programs(enum hid_bpf_prog_type type) { switch (type) { case HID_BPF_PROG_TYPE_DEVICE_EVENT: + case HID_BPF_PROG_TYPE_RAW_REQUEST: return HID_BPF_MAX_PROGS_PER_DEV; case HID_BPF_PROG_TYPE_RDESC_FIXUP: return 1; diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index b8414ce62e7b..7d468f6dbefe 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -2407,6 +2407,7 @@ int __hid_hw_raw_request(struct hid_device *hdev, __u64 source) { unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE; + u32 size = (u32)len; /* max_buffer_size is 16 KB */ if (hdev->ll_driver->max_buffer_size) max_buffer_size = hdev->ll_driver->max_buffer_size; @@ -2414,7 +2415,12 @@ int __hid_hw_raw_request(struct hid_device *hdev, if (len < 1 || len > max_buffer_size || !buf) return -EINVAL; - return hdev->ll_driver->raw_request(hdev, reportnum, buf, len, + buf = dispatch_hid_bpf_raw_requests(hdev, reportnum, buf, &size, rtype, + reqtype, source); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + return hdev->ll_driver->raw_request(hdev, reportnum, buf, size, rtype, reqtype); } diff --git a/include/linux/hid_bpf.h b/include/linux/hid_bpf.h index 6bcaf19f1cc2..1cd36bfdd608 100644 --- a/include/linux/hid_bpf.h +++ b/include/linux/hid_bpf.h @@ -52,10 +52,12 @@ struct hid_bpf_ctx { __u64 source; const struct hid_device *hid; enum hid_report_type report_type; + enum hid_class_request reqtype; /* for HID_BPF_PROG_TYPE_RAW_REQUEST */ union { __s32 retval; __s32 size; }; + __u8 reportnum; }; /** @@ -77,6 +79,7 @@ enum hid_bpf_attach_flags { /* Following functions are tracepoints that BPF programs can attach to */ int hid_bpf_device_event(struct hid_bpf_ctx *ctx); int hid_bpf_rdesc_fixup(struct hid_bpf_ctx *ctx); +int hid_bpf_raw_request(struct hid_bpf_ctx *ctx); /* * Below is HID internal @@ -90,6 +93,7 @@ enum hid_bpf_prog_type { HID_BPF_PROG_TYPE_UNDEF = -1, HID_BPF_PROG_TYPE_DEVICE_EVENT, /* an event is emitted from the device */ HID_BPF_PROG_TYPE_RDESC_FIXUP, + HID_BPF_PROG_TYPE_RAW_REQUEST, HID_BPF_PROG_TYPE_MAX, }; @@ -140,6 +144,11 @@ struct hid_bpf_link { #ifdef CONFIG_HID_BPF u8 *dispatch_hid_bpf_device_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 *size, int interrupt, u64 source); +u8 *dispatch_hid_bpf_raw_requests(struct hid_device *hdev, + unsigned char reportnum, __u8 *buf, + u32 *size, enum hid_report_type rtype, + enum hid_class_request reqtype, + __u64 source); int hid_bpf_connect_device(struct hid_device *hdev); void hid_bpf_disconnect_device(struct hid_device *hdev); void hid_bpf_destroy_device(struct hid_device *hid); @@ -149,6 +158,11 @@ u8 *call_hid_bpf_rdesc_fixup(struct hid_device *hdev, u8 *rdesc, unsigned int *s static inline u8 *dispatch_hid_bpf_device_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 *size, int interrupt, u64 source) { return data; } +static inline u8 *dispatch_hid_bpf_raw_requests(struct hid_device *hdev, + unsigned char reportnum, u8 *buf, + u32 *size, enum hid_report_type rtype, + enum hid_class_request reqtype, + u64 source) { return buf; } static inline int hid_bpf_connect_device(struct hid_device *hdev) { return 0; } static inline void hid_bpf_disconnect_device(struct hid_device *hdev) {} static inline void hid_bpf_destroy_device(struct hid_device *hid) {}

[RFC,HID,5/7] WIP: add HID-BPF hooks for hid_hw_raw_requests

Checks

Commit Message

Patch