6.12-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Torokhov dmitry.torokhov@gmail.com
[ Upstream commit c653ffc283404a6c1c0e65143a833180c7ff799b ]
The only user of hid_snto32() is Logitech HID++ driver, which always calls hid_snto32() with valid size (constant, either 12 or 8) and therefore can simply use sign_extend32().
Make the switch and remove hid_snto32(). Move snto32() and s32ton() to avoid introducing forward declaration.
Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Link: https://patch.msgid.link/20241003144656.3786064-2-dmitry.torokhov@gmail.com [bentiss: fix checkpatch warning] Signed-off-by: Benjamin Tissoires bentiss@kernel.org Stable-dep-of: a6b87bfc2ab5 ("HID: core: Harden s32ton() against conversion to 0 bits") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hid/hid-core.c | 63 +++++++++++++++----------------- drivers/hid/hid-logitech-hidpp.c | 6 +-- include/linux/hid.h | 1 - 3 files changed, 32 insertions(+), 38 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 1a8e88624acfb..5169d8d56c889 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -45,6 +45,34 @@ static int hid_ignore_special_drivers = 0; module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600); MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver");
+/* + * Convert a signed n-bit integer to signed 32-bit integer. + */ + +static s32 snto32(__u32 value, unsigned int n) +{ + if (!value || !n) + return 0; + + if (n > 32) + n = 32; + + return sign_extend32(value, n - 1); +} + +/* + * Convert a signed 32-bit integer to a signed n-bit integer. + */ + +static u32 s32ton(__s32 value, unsigned int n) +{ + s32 a = value >> (n - 1); + + if (a && a != -1) + return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; + return value & ((1 << n) - 1); +} + /* * Register a new report for a device. */ @@ -425,7 +453,7 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) * both this and the standard encoding. */ raw_value = item_sdata(item); if (!(raw_value & 0xfffffff0)) - parser->global.unit_exponent = hid_snto32(raw_value, 4); + parser->global.unit_exponent = snto32(raw_value, 4); else parser->global.unit_exponent = raw_value; return 0; @@ -1317,39 +1345,6 @@ int hid_open_report(struct hid_device *device) } EXPORT_SYMBOL_GPL(hid_open_report);
-/* - * Convert a signed n-bit integer to signed 32-bit integer. - */ - -static s32 snto32(__u32 value, unsigned n) -{ - if (!value || !n) - return 0; - - if (n > 32) - n = 32; - - return sign_extend32(value, n - 1); -} - -s32 hid_snto32(__u32 value, unsigned n) -{ - return snto32(value, n); -} -EXPORT_SYMBOL_GPL(hid_snto32); - -/* - * Convert a signed 32-bit integer to a signed n-bit integer. - */ - -static u32 s32ton(__s32 value, unsigned n) -{ - s32 a = value >> (n - 1); - if (a && a != -1) - return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; - return value & ((1 << n) - 1); -} - /* * Extract/implement a data field from/to a little endian report (bit array). * diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index 234ddd4422d90..59f630962338d 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -3296,13 +3296,13 @@ static int m560_raw_event(struct hid_device *hdev, u8 *data, int size) 120); }
- v = hid_snto32(hid_field_extract(hdev, data+3, 0, 12), 12); + v = sign_extend32(hid_field_extract(hdev, data + 3, 0, 12), 11); input_report_rel(hidpp->input, REL_X, v);
- v = hid_snto32(hid_field_extract(hdev, data+3, 12, 12), 12); + v = sign_extend32(hid_field_extract(hdev, data + 3, 12, 12), 11); input_report_rel(hidpp->input, REL_Y, v);
- v = hid_snto32(data[6], 8); + v = sign_extend32(data[6], 7); if (v != 0) hidpp_scroll_counter_handle_scroll(hidpp->input, &hidpp->vertical_wheel_counter, v); diff --git a/include/linux/hid.h b/include/linux/hid.h index 017d31f1d27b8..7d8d09318fa91 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -978,7 +978,6 @@ const struct hid_device_id *hid_match_device(struct hid_device *hdev, struct hid_driver *hdrv); bool hid_compare_device_paths(struct hid_device *hdev_a, struct hid_device *hdev_b, char separator); -s32 hid_snto32(__u32 value, unsigned n); __u32 hid_field_extract(const struct hid_device *hid, __u8 *report, unsigned offset, unsigned n);