[PATCH 5.10 047/589] HID: alps: fix NULL pointer dereference in alps_raw_event()

[PATCH 5.10 047/589] HID: alps: fix NULL pointer dereference in alps_raw_event()

[Greg Kroah-Hartman]

5.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 1badfc4319224820d5d890f8eab6aa52e4e83339 upstream.

Commit ecfa6f34492c ("HID: Add HID_CLAIMED_INPUT guards in raw_event
callbacks missing them") attempted to fix up the HID drivers that had
missed the previous fix that was done in 2ff5baa9b527 ("HID: appleir:
Fix potential NULL dereference at raw event handle"), but the alps
driver was missed.

Fix this up by properly checking in the hid-alps driver that it had been
claimed correctly before attempting to process the raw event.

Fixes: 73196ebe134d ("HID: alps: add support for Alps T4 Touchpad device")
Cc: stable <stable@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <bentiss@kernel.org>
Cc: Masaki Ota <masaki.ota@jp.alps.com>
Cc: linux-input@vger.kernel.org
Assisted-by: gregkh_clanker_t1000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/hid/hid-alps.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/hid/hid-alps.c
+++ b/drivers/hid/hid-alps.c
@@ -437,6 +437,9 @@ static int alps_raw_event(struct hid_dev
 	int ret = 0;
 	struct alps_dev *hdata = hid_get_drvdata(hdev);
 
+	if (!(hdev->claimed & HID_CLAIMED_INPUT) || !hdata->input)
+		return 0;
+
 	switch (hdev->product) {
 	case HID_PRODUCT_ID_T4_BTNLESS:
 		ret = t4_raw_event(hdata, data, size);

[PATCH 5.10 048/589] HID: core: clamp report_size in s32ton() to avoid undefined shift

[Greg Kroah-Hartman]

5.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 69c02ffde6ed4d535fa4e693a9e572729cad3d0d upstream.

s32ton() shifts by n-1 where n is the field's report_size, a value that
comes directly from a HID device.  The HID parser bounds report_size
only to <= 256, so a broken HID device can supply a report descriptor
with a wide field that triggers shift exponents up to 256 on a 32-bit
type when an output report is built via hid_output_field() or
hid_set_field().

Commit ec61b41918587 ("HID: core: fix shift-out-of-bounds in
hid_report_raw_event") added the same n > 32 clamp to the function
snto32(), but s32ton() was never given the same fix as I guess syzbot
hadn't figured out how to fuzz a device the same way.

Fix this up by just clamping the max value of n, just like snto32()
does.

Cc: stable <stable@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <bentiss@kernel.org>
Cc: linux-input@vger.kernel.org
Assisted-by: gregkh_clanker_t1000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/hid/hid-core.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1354,6 +1354,9 @@ static u32 s32ton(__s32 value, unsigned
 	if (!value || !n)
 		return 0;
 
+	if (n > 32)
+		n = 32;
+
 	a = value >> (n - 1);
 	if (a && a != -1)
 		return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1;