commit 0a3fe972a7cb ("HID: core: Mitigate potential OOB by removing bogus memset()") enforced the provided data to be at least the size of the declared buffer in the report descriptor to prevent a buffer overflow. However, we can try to be smarter by providing both the buffer size and the data size, meaning that hid_report_raw_event() can make better decision whether we should plaining reject the buffer (buffer overflow attempt) or if we can safely memset it to 0 and pass it to the rest of the stack.

Fixes: 0a3fe972a7cb ("HID: core: Mitigate potential OOB by removing bogus memset()") Cc: stable@vger.kernel.org Signed-off-by: Benjamin Tissoires bentiss@kernel.org --- drivers/hid/bpf/hid_bpf_dispatch.c | 6 ++++-- drivers/hid/hid-core.c | 42 +++++++++++++++++++++++++------------- drivers/hid/hid-gfrm.c | 4 ++-- drivers/hid/hid-logitech-hidpp.c | 2 +- drivers/hid/hid-multitouch.c | 2 +- drivers/hid/hid-primax.c | 2 +- drivers/hid/hid-vivaldi-common.c | 2 +- drivers/hid/wacom_sys.c | 6 +++--- drivers/staging/greybus/hid.c | 2 +- include/linux/hid.h | 4 ++-- include/linux/hid_bpf.h | 14 ++++++++----- 11 files changed, 53 insertions(+), 33 deletions(-)

diff --git a/drivers/hid/bpf/hid_bpf_dispatch.c b/drivers/hid/bpf/hid_bpf_dispatch.c index 50c7b45c59e3..d0130658091b 100644 --- a/drivers/hid/bpf/hid_bpf_dispatch.c +++ b/drivers/hid/bpf/hid_bpf_dispatch.c @@ -24,7 +24,8 @@ EXPORT_SYMBOL(hid_ops);

u8 * dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type, u8 *data, - u32 *size, int interrupt, u64 source, bool from_bpf) + size_t *buf_size, u32 *size, int interrupt, u64 source, + bool from_bpf) { struct hid_bpf_ctx_kern ctx_kern = { .ctx = { @@ -74,6 +75,7 @@ dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type *size = ret; }

+ *buf_size = ctx_kern.ctx.allocated_size; return ctx_kern.data; } EXPORT_SYMBOL_GPL(dispatch_hid_bpf_device_event); @@ -505,7 +507,7 @@ __hid_bpf_input_report(struct hid_bpf_ctx *ctx, enum hid_report_type type, u8 *b if (ret) return ret;

- return hid_ops->hid_input_report(ctx->hid, type, buf, size, 0, (u64)(long)ctx, true, + return hid_ops->hid_input_report(ctx->hid, type, buf, size, size, 0, (u64)(long)ctx, true, lock_already_taken); }

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 61afec5915ec..a806820df7e5 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -2033,24 +2033,32 @@ int __hid_request(struct hid_device *hid, struct hid_report *report, } EXPORT_SYMBOL_GPL(__hid_request);

-int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, - int interrupt) +int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, + size_t bufsize, u32 size, int interrupt) { struct hid_report_enum *report_enum = hid->report_enum + type; struct hid_report *report; struct hid_driver *hdrv; int max_buffer_size = HID_MAX_BUFFER_SIZE; u32 rsize, csize = size; + size_t bsize = bufsize; u8 *cdata = data; int ret = 0;

report = hid_get_report(report_enum, data); if (!report) - goto out; + return 0; + + if (unlikely(bsize < csize)) { + hid_warn_ratelimited(hid, "Event data for report %d is incorrect (%d vs %ld)\n", + report->id, csize, bsize); + return -EINVAL; + }

if (report_enum->numbered) { cdata++; csize--; + bsize--; }

rsize = hid_compute_report_size(report); @@ -2063,11 +2071,16 @@ int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 * else if (rsize > max_buffer_size) rsize = max_buffer_size;

+ if (bsize < rsize) { + hid_warn_ratelimited(hid, "Event data for report %d was too short (%d vs %ld)\n", + report->id, rsize, bsize); + return -EINVAL; + } + if (csize < rsize) { - hid_warn_ratelimited(hid, "Event data for report %d was too short (%d vs %d)\n", - report->id, rsize, csize); - ret = -EINVAL; - goto out; + dbg_hid("report %d is too short, (%d < %d)\n", report->id, + csize, rsize); + memset(cdata + csize, 0, rsize - csize); }

if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) @@ -2075,7 +2088,7 @@ int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 * if (hid->claimed & HID_CLAIMED_HIDRAW) { ret = hidraw_report_event(hid, data, size); if (ret) - goto out; + return ret; }

if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) { @@ -2087,15 +2100,15 @@ int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *

if (hid->claimed & HID_CLAIMED_INPUT) hidinput_report_event(hid, report); -out: + return ret; } EXPORT_SYMBOL_GPL(hid_report_raw_event);

static int __hid_input_report(struct hid_device *hid, enum hid_report_type type, - u8 *data, u32 size, int interrupt, u64 source, bool from_bpf, - bool lock_already_taken) + u8 *data, size_t bufsize, u32 size, int interrupt, u64 source, + bool from_bpf, bool lock_already_taken) { struct hid_report_enum *report_enum; struct hid_driver *hdrv; @@ -2120,7 +2133,8 @@ static int __hid_input_report(struct hid_device *hid, enum hid_report_type type, report_enum = hid->report_enum + type; hdrv = hid->driver;

- data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt, source, from_bpf); + data = dispatch_hid_bpf_device_event(hid, type, data, &bufsize, &size, interrupt, + source, from_bpf); if (IS_ERR(data)) { ret = PTR_ERR(data); goto unlock; @@ -2149,7 +2163,7 @@ static int __hid_input_report(struct hid_device *hid, enum hid_report_type type, goto unlock; }

- ret = hid_report_raw_event(hid, type, data, size, interrupt); + ret = hid_report_raw_event(hid, type, data, bufsize, size, interrupt);

unlock: if (!lock_already_taken) @@ -2171,7 +2185,7 @@ static int __hid_input_report(struct hid_device *hid, enum hid_report_type type, int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, int interrupt) { - return __hid_input_report(hid, type, data, size, interrupt, 0, + return __hid_input_report(hid, type, data, size, size, interrupt, 0, false, /* from_bpf */ false /* lock_already_taken */); } diff --git a/drivers/hid/hid-gfrm.c b/drivers/hid/hid-gfrm.c index 699186ff2349..d2a56bf92b41 100644 --- a/drivers/hid/hid-gfrm.c +++ b/drivers/hid/hid-gfrm.c @@ -66,7 +66,7 @@ static int gfrm_raw_event(struct hid_device *hdev, struct hid_report *report, switch (data[1]) { case GFRM100_SEARCH_KEY_DOWN: ret = hid_report_raw_event(hdev, HID_INPUT_REPORT, search_key_dn, - sizeof(search_key_dn), 1); + sizeof(search_key_dn), sizeof(search_key_dn), 1); break;

case GFRM100_SEARCH_KEY_AUDIO_DATA: @@ -74,7 +74,7 @@ static int gfrm_raw_event(struct hid_device *hdev, struct hid_report *report,

case GFRM100_SEARCH_KEY_UP: ret = hid_report_raw_event(hdev, HID_INPUT_REPORT, search_key_up, - sizeof(search_key_up), 1); + sizeof(search_key_up), sizeof(search_key_up), 1); break;

default: diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index b1330d23bd2d..b3ff9265377b 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -3673,7 +3673,7 @@ static int hidpp10_consumer_keys_raw_event(struct hidpp_device *hidpp, memcpy(&consumer_report[1], &data[3], 4); /* We are called from atomic context */ hid_report_raw_event(hidpp->hid_dev, HID_INPUT_REPORT, - consumer_report, 5, 1); + consumer_report, sizeof(consumer_report), 5, 1);

return 1; } diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index e82a3c4e5b44..eeab0b6e32cc 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -533,7 +533,7 @@ static void mt_get_feature(struct hid_device *hdev, struct hid_report *report) }

ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, buf, - size, 0); + size, size, 0); if (ret) dev_warn(&hdev->dev, "failed to report feature\n"); } diff --git a/drivers/hid/hid-primax.c b/drivers/hid/hid-primax.c index e44d79dff8de..8db054280afb 100644 --- a/drivers/hid/hid-primax.c +++ b/drivers/hid/hid-primax.c @@ -44,7 +44,7 @@ static int px_raw_event(struct hid_device *hid, struct hid_report *report, data[0] |= (1 << (data[idx] - 0xE0)); data[idx] = 0; } - hid_report_raw_event(hid, HID_INPUT_REPORT, data, size, 0); + hid_report_raw_event(hid, HID_INPUT_REPORT, data, size, size, 0); return 1;

default: /* unknown report */ diff --git a/drivers/hid/hid-vivaldi-common.c b/drivers/hid/hid-vivaldi-common.c index bf734055d4b6..b12bb5cc091a 100644 --- a/drivers/hid/hid-vivaldi-common.c +++ b/drivers/hid/hid-vivaldi-common.c @@ -85,7 +85,7 @@ void vivaldi_feature_mapping(struct hid_device *hdev, }

ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, report_data, - report_len, 0); + report_len, report_len, 0); if (ret) { dev_warn(&hdev->dev, "failed to report feature %d\n", field->report->id); diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c index 0d1c6d90fe21..a32320b351e3 100644 --- a/drivers/hid/wacom_sys.c +++ b/drivers/hid/wacom_sys.c @@ -90,7 +90,7 @@ static void wacom_wac_queue_flush(struct hid_device *hdev, kfree(buf); continue; } - err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, false); + err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, size, false); if (err) { hid_warn(hdev, "%s: unable to flush event due to error %d\n", __func__, err); @@ -334,7 +334,7 @@ static void wacom_feature_mapping(struct hid_device *hdev, data, n, WAC_CMD_RETRIES); if (ret == n && features->type == HID_GENERIC) { ret = hid_report_raw_event(hdev, - HID_FEATURE_REPORT, data, n, 0); + HID_FEATURE_REPORT, data, n, n, 0); } else if (ret == 2 && features->type != HID_GENERIC) { features->touch_max = data[1]; } else { @@ -395,7 +395,7 @@ static void wacom_feature_mapping(struct hid_device *hdev, data, n, WAC_CMD_RETRIES); if (ret == n) { ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, - data, n, 0); + data, n, n, 0); } else { hid_warn(hdev, "%s: could not retrieve sensor offsets\n", __func__); diff --git a/drivers/staging/greybus/hid.c b/drivers/staging/greybus/hid.c index 1f58c907c036..f1f9f6fbc00e 100644 --- a/drivers/staging/greybus/hid.c +++ b/drivers/staging/greybus/hid.c @@ -201,7 +201,7 @@ static void gb_hid_init_report(struct gb_hid *ghid, struct hid_report *report) * we just need to setup the input fields, so using * hid_report_raw_event is safe. */ - hid_report_raw_event(ghid->hid, report->type, ghid->inbuf, size, 1); + hid_report_raw_event(ghid->hid, report->type, ghid->inbuf, ghid->bufsize, size, 1); }

static void gb_hid_init_reports(struct gb_hid *ghid) diff --git a/include/linux/hid.h b/include/linux/hid.h index 442a80d79e89..ac432a2ef415 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -1298,8 +1298,8 @@ static inline u32 hid_report_len(struct hid_report *report) return DIV_ROUND_UP(report->size, 8) + (report->id > 0); }

-int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, - int interrupt); +int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 *data, + size_t bufsize, u32 size, int interrupt);

/* HID quirks API */ unsigned long hid_lookup_quirk(const struct hid_device *hdev); diff --git a/include/linux/hid_bpf.h b/include/linux/hid_bpf.h index a2e47dbcf82c..19fffa4574a4 100644 --- a/include/linux/hid_bpf.h +++ b/include/linux/hid_bpf.h @@ -72,8 +72,8 @@ struct hid_ops { int (*hid_hw_output_report)(struct hid_device *hdev, __u8 *buf, size_t len, u64 source, bool from_bpf); int (*hid_input_report)(struct hid_device *hid, enum hid_report_type type, - u8 *data, u32 size, int interrupt, u64 source, bool from_bpf, - bool lock_already_taken); + u8 *data, size_t bufsize, u32 size, int interrupt, u64 source, + bool from_bpf, bool lock_already_taken); struct module *owner; const struct bus_type *bus_type; }; @@ -200,7 +200,8 @@ struct hid_bpf {

#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, bool from_bpf); + size_t *buf_size, u32 *size, int interrupt, u64 source, + bool from_bpf); int dispatch_hid_bpf_raw_requests(struct hid_device *hdev, unsigned char reportnum, __u8 *buf, u32 size, enum hid_report_type rtype, @@ -215,8 +216,11 @@ int hid_bpf_device_init(struct hid_device *hid); const u8 *call_hid_bpf_rdesc_fixup(struct hid_device *hdev, const u8 *rdesc, unsigned int *size); #else /* CONFIG_HID_BPF */ 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, bool from_bpf) { return data; } + u8 *data, size_t *buf_size, u32 *size, + int interrupt, u64 source, bool from_bpf) +{ + return data; +} static inline int dispatch_hid_bpf_raw_requests(struct hid_device *hdev, unsigned char reportnum, u8 *buf, u32 size, enum hid_report_type rtype,

hid_input_report() is used in too many places to have a commit that doesn't cross subsystem borders. Instead of changing the API, introduce a new one when things matters in the transport layers: - usbhid - i2chid

This effectively revert to the old behavior for those two transport layers.

Fixes: 0a3fe972a7cb ("HID: core: Mitigate potential OOB by removing bogus memset()") Cc: stable@vger.kernel.org Signed-off-by: Benjamin Tissoires bentiss@kernel.org --- drivers/hid/hid-core.c | 25 +++++++++++++++++++++++++ drivers/hid/i2c-hid/i2c-hid-core.c | 7 ++++--- drivers/hid/usbhid/hid-core.c | 11 ++++++----- include/linux/hid.h | 2 ++ 4 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index a806820df7e5..b3596851c719 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -2181,6 +2181,7 @@ static int __hid_input_report(struct hid_device *hid, enum hid_report_type type, * @interrupt: distinguish between interrupt and control transfers * * This is data entry for lower layers. + * Legacy, please use hid_safe_input_report() instead. */ int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, int interrupt) @@ -2191,6 +2192,30 @@ int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data } EXPORT_SYMBOL_GPL(hid_input_report);

+/** + * hid_safe_input_report - report data from lower layer (usb, bt...) + * + * @hid: hid device + * @type: HID report type (HID_*_REPORT) + * @data: report contents + * @bufsize: allocated size of the data buffer + * @size: useful size of data parameter + * @interrupt: distinguish between interrupt and control transfers + * + * This is data entry for lower layers. + * Please use this function instead of the non safe version because we provide + * here the size of the buffer, allowing hid-core to make smarter decisions + * regarding the incoming buffer. + */ +int hid_safe_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, + size_t bufsize, u32 size, int interrupt) +{ + return __hid_input_report(hid, type, data, bufsize, size, interrupt, 0, + false, /* from_bpf */ + false /* lock_already_taken */); +} +EXPORT_SYMBOL_GPL(hid_safe_input_report); + bool hid_match_one_id(const struct hid_device *hdev, const struct hid_device_id *id) { diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c index 5a183af3d5c6..e0a302544cef 100644 --- a/drivers/hid/i2c-hid/i2c-hid-core.c +++ b/drivers/hid/i2c-hid/i2c-hid-core.c @@ -574,9 +574,10 @@ static void i2c_hid_get_input(struct i2c_hid *ihid) if (ihid->hid->group != HID_GROUP_RMI) pm_wakeup_event(&ihid->client->dev, 0);

- hid_input_report(ihid->hid, HID_INPUT_REPORT, - ihid->inbuf + sizeof(__le16), - ret_size - sizeof(__le16), 1); + hid_safe_input_report(ihid->hid, HID_INPUT_REPORT, + ihid->inbuf + sizeof(__le16), + ihid->bufsize - sizeof(__le16), + ret_size - sizeof(__le16), 1); }

return; diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c index fbbfc0f60829..5af93b9b1fb5 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -283,9 +283,9 @@ static void hid_irq_in(struct urb *urb) break; usbhid_mark_busy(usbhid); if (!test_bit(HID_RESUME_RUNNING, &usbhid->iofl)) { - hid_input_report(urb->context, HID_INPUT_REPORT, - urb->transfer_buffer, - urb->actual_length, 1); + hid_safe_input_report(urb->context, HID_INPUT_REPORT, + urb->transfer_buffer, urb->transfer_buffer_length, + urb->actual_length, 1); /* * autosuspend refused while keys are pressed * because most keyboards don't wake up when @@ -482,9 +482,10 @@ static void hid_ctrl(struct urb *urb) switch (status) { case 0: /* success */ if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_IN) - hid_input_report(urb->context, + hid_safe_input_report(urb->context, usbhid->ctrl[usbhid->ctrltail].report->type, - urb->transfer_buffer, urb->actual_length, 0); + urb->transfer_buffer, urb->transfer_buffer_length, + urb->actual_length, 0); break; case -ESHUTDOWN: /* unplug */ unplug = 1; diff --git a/include/linux/hid.h b/include/linux/hid.h index ac432a2ef415..bfb9859f391e 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -1030,6 +1030,8 @@ struct hid_field *hid_find_field(struct hid_device *hdev, unsigned int report_ty int hid_set_field(struct hid_field *, unsigned, __s32); int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size, int interrupt); +int hid_safe_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, + size_t bufsize, u32 size, int interrupt); struct hid_field *hidinput_get_led_field(struct hid_device *hid); unsigned int hidinput_count_leds(struct hid_device *hid); __s32 hidinput_calc_abs_res(const struct hid_field *field, __u16 code);

This simplifies error handling and protects against memory leaks.

Signed-off-by: Benjamin Tissoires bentiss@kernel.org --- drivers/hid/hid-core.c | 4 ++-- drivers/hid/wacom_sys.c | 40 +++++++++++++--------------------------- 2 files changed, 15 insertions(+), 29 deletions(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index b3596851c719..7fc20e0405ad 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -2050,8 +2050,8 @@ int hid_report_raw_event(struct hid_device *hid, enum hid_report_type type, u8 * return 0;

if (unlikely(bsize < csize)) { - hid_warn_ratelimited(hid, "Event data for report %d is incorrect (%d vs %ld)\n", - report->id, csize, bsize); + hid_warn_ratelimited(hid, "Event data for report %d is incorrect (%d vs %d)\n", + report->id, csize, (unsigned int)bsize); return -EINVAL; }

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c index a32320b351e3..adb31f54e524 100644 --- a/drivers/hid/wacom_sys.c +++ b/drivers/hid/wacom_sys.c @@ -70,11 +70,10 @@ static void wacom_wac_queue_flush(struct hid_device *hdev, { while (!kfifo_is_empty(fifo)) { int size = kfifo_peek_len(fifo); - u8 *buf; unsigned int count; int err;

- buf = kzalloc(size, GFP_KERNEL); + u8 *buf __free(kfree) = kzalloc(size, GFP_KERNEL); if (!buf) { kfifo_skip(fifo); continue; @@ -87,7 +86,6 @@ static void wacom_wac_queue_flush(struct hid_device *hdev, // to flush seems reasonable enough, however. hid_warn(hdev, "%s: removed fifo entry with unexpected size\n", __func__); - kfree(buf); continue; } err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, size, false); @@ -95,8 +93,6 @@ static void wacom_wac_queue_flush(struct hid_device *hdev, hid_warn(hdev, "%s: unable to flush event due to error %d\n", __func__, err); } - - kfree(buf); } }

@@ -311,7 +307,6 @@ static void wacom_feature_mapping(struct hid_device *hdev, struct wacom_features *features = &wacom->wacom_wac.features; struct hid_data *hid_data = &wacom->wacom_wac.hid_data; unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid); - u8 *data; int ret; u32 n;

@@ -325,10 +320,11 @@ static void wacom_feature_mapping(struct hid_device *hdev, /* leave touch_max as is if predefined */ if (!features->touch_max) { /* read manually */ - n = hid_report_len(field->report); - data = hid_alloc_report_buf(field->report, GFP_KERNEL); + u8 *data __free(kfree) = hid_alloc_report_buf(field->report, GFP_KERNEL); + if (!data) break; + n = hid_report_len(field->report); data[0] = field->report->id; ret = wacom_get_report(hdev, HID_FEATURE_REPORT, data, n, WAC_CMD_RETRIES); @@ -344,7 +340,6 @@ static void wacom_feature_mapping(struct hid_device *hdev, "defaulting to %d\n", features->touch_max); } - kfree(data); } break; case HID_DG_INPUTMODE: @@ -386,10 +381,11 @@ static void wacom_feature_mapping(struct hid_device *hdev, case WACOM_HID_WD_OFFSETRIGHT: case WACOM_HID_WD_OFFSETBOTTOM: /* read manually */ - n = hid_report_len(field->report); - data = hid_alloc_report_buf(field->report, GFP_KERNEL); + u8 *data __free(kfree) = hid_alloc_report_buf(field->report, GFP_KERNEL); + if (!data) break; + n = hid_report_len(field->report); data[0] = field->report->id; ret = wacom_get_report(hdev, HID_FEATURE_REPORT, data, n, WAC_CMD_RETRIES); @@ -400,7 +396,6 @@ static void wacom_feature_mapping(struct hid_device *hdev, hid_warn(hdev, "%s: could not retrieve sensor offsets\n", __func__); } - kfree(data); break; } } @@ -581,7 +576,6 @@ static int wacom_hid_set_device_mode(struct hid_device *hdev) static int wacom_set_device_mode(struct hid_device *hdev, struct wacom_wac *wacom_wac) { - u8 *rep_data; struct hid_report *r; struct hid_report_enum *re; u32 length; @@ -595,7 +589,7 @@ static int wacom_set_device_mode(struct hid_device *hdev, if (!r) return -EINVAL;

- rep_data = hid_alloc_report_buf(r, GFP_KERNEL); + u8 *rep_data __free(kfree) = hid_alloc_report_buf(r, GFP_KERNEL); if (!rep_data) return -ENOMEM;

@@ -614,8 +608,6 @@ static int wacom_set_device_mode(struct hid_device *hdev, rep_data[1] != wacom_wac->mode_report && limit++ < WAC_MSG_RETRIES);

- kfree(rep_data); - return error < 0 ? error : 0; }

@@ -921,7 +913,6 @@ static int wacom_add_shared_data(struct hid_device *hdev)

static int wacom_led_control(struct wacom *wacom) { - unsigned char *buf; int retval; unsigned char report_id = WAC_CMD_LED_CONTROL; int buf_size = 9; @@ -940,7 +931,8 @@ static int wacom_led_control(struct wacom *wacom) report_id = WAC_CMD_WL_INTUOSP2; buf_size = 51; } - buf = kzalloc(buf_size, GFP_KERNEL); + + unsigned char *buf __free(kfree) = kzalloc(buf_size, GFP_KERNEL); if (!buf) return -ENOMEM;

@@ -996,7 +988,6 @@ static int wacom_led_control(struct wacom *wacom)

retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, buf_size, WAC_CMD_RETRIES); - kfree(buf);

return retval; } @@ -1004,11 +995,10 @@ static int wacom_led_control(struct wacom *wacom) static int wacom_led_putimage(struct wacom *wacom, int button_id, u8 xfer_id, const unsigned len, const void *img) { - unsigned char *buf; int i, retval; const unsigned chunk_len = len / 4; /* 4 chunks are needed to be sent */

- buf = kzalloc(chunk_len + 3 , GFP_KERNEL); + unsigned char *buf __free(kfree) = kzalloc(chunk_len + 3, GFP_KERNEL); if (!buf) return -ENOMEM;

@@ -1018,7 +1008,7 @@ static int wacom_led_putimage(struct wacom *wacom, int button_id, u8 xfer_id, retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, 2, WAC_CMD_RETRIES); if (retval < 0) - goto out; + return retval;

buf[0] = xfer_id; buf[1] = button_id & 0x07; @@ -1038,8 +1028,6 @@ static int wacom_led_putimage(struct wacom *wacom, int button_id, u8 xfer_id, wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, 2, WAC_CMD_RETRIES);

-out: - kfree(buf); return retval; }

@@ -1948,10 +1936,9 @@ static int wacom_remote_create_attr_group(struct wacom *wacom, __u32 serial, static int wacom_cmd_unpair_remote(struct wacom *wacom, unsigned char selector) { const size_t buf_size = 2; - unsigned char *buf; int retval;

- buf = kzalloc(buf_size, GFP_KERNEL); + unsigned char *buf __free(kfree) = kzalloc(buf_size, GFP_KERNEL); if (!buf) return -ENOMEM;

@@ -1960,7 +1947,6 @@ static int wacom_cmd_unpair_remote(struct wacom *wacom, unsigned char selector)

retval = wacom_set_report(wacom->hdev, HID_OUTPUT_REPORT, buf, buf_size, WAC_CMD_RETRIES); - kfree(buf);

return retval; }