FAILED: patch "[PATCH] HID: pidff: fix OOB write when hid->inputs is empty" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] HID: pidff: fix OOB write when hid->inputs is empty" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 67bb1074e3d2d12fa059a9cc707e89398a4e4704
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026082517-petroleum-anaerobic-3fd3@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 67bb1074e3d2d12fa059a9cc707e89398a4e4704 Mon Sep 17 00:00:00 2001
From: Baul Lee <baul.lee@xbow.com>
Date: Sun, 26 Jul 2026 15:25:03 +0900
Subject: [PATCH] HID: pidff: fix OOB write when hid->inputs is empty

hid_pidff_init_with_quirks() derives its input_dev from

	list_entry(hid->inputs.next, struct hid_input, list)

without first checking that hid->inputs is non-empty.  The list member
of struct hid_input is at offset 0, so on an empty list list_entry()
yields &hid->inputs itself and the following hidinput->input load reads
an unrelated member of struct hid_device.  dev is then a type-confused
pointer, and force-feedback init writes through it: each
set_bit(FF_*, dev->ffbit) stores 8 bytes at dev + 192, past the end of
the object dev actually aliases, and input_ff_create() adds further
writes of a heap pointer and two function pointers.

Until hid-universal-pidff the only caller was hid_pidff_init() from
usbhid, which runs under HID_CLAIMED_INPUT and therefore always has at
least one hid_input.  universal_pidff_probe() starts the device with
HID_CONNECT_DEFAULT & ~HID_CONNECT_FF and then calls
hid_pidff_init_with_quirks() directly whenever the descriptor carries a
PID usage page, bypassing that gate.  A report descriptor whose only
application collection is on HID_UP_PID leaves hid->inputs empty while
hid_connect() still succeeds through the hidraw claim, so probe reaches
the unguarded list_entry().

The write happens in the USB probe path, on the hotplug workqueue, so
plugging in a malicious device is enough to trigger it; no attacker
software and no logged-in user are required.  KASAN reports an 8-byte
out-of-bounds write in hid_pidff_init_with_quirks() reached from
universal_pidff_probe().

Check for an empty list before deriving dev and return -ENODEV, as the
other HID force-feedback drivers already do.  universal_pidff_probe()
propagates the error and unwinds.

Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>

Fixes: f06bf8d94fff ("HID: Add hid-universal-pidff driver and supported device ids")
Reported-by: Federico Kirschbaum <federico.kirschbaum@xbow.com>
Reported-by: Baul Lee <baul.lee@xbow.com>
Cc: stable@vger.kernel.org
Signed-off-by: Baul Lee <baul.lee@xbow.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index 5f4395f7c645..22951b7ecd17 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -1539,13 +1539,20 @@ static int pidff_check_autocenter(struct pidff_device *pidff,
 int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks)
 {
 	struct pidff_device *pidff;
-	struct hid_input *hidinput =
-		list_entry(hid->inputs.next, struct hid_input, list);
-	struct input_dev *dev = hidinput->input;
+	struct hid_input *hidinput;
+	struct input_dev *dev;
 	struct ff_device *ff;
 	int max_effects;
 	int error;
 
+	if (list_empty(&hid->inputs)) {
+		hid_err(hid, "no inputs found\n");
+		return -ENODEV;
+	}
+
+	hidinput = list_first_entry(&hid->inputs, struct hid_input, list);
+	dev = hidinput->input;
+
 	hid_dbg(hid, "starting pid init\n");
 
 	if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {

[PATCH 6.12.y 1/4] HID: pidff: Rework pidff_set_time() to fix warnings

[Sasha Levin]

From: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>

[ Upstream commit bed72bd240ce77623845853397b89a08f6dc5770 ]

Fixes blank line warning from checkpatch.pl script

Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Stable-dep-of: 67bb1074e3d2 ("HID: pidff: fix OOB write when hid->inputs is empty")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hid/usbhid/hid-pidff.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index 0e653b104b525..471dbc8fabc98 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -339,8 +339,8 @@ static void pidff_set_signed(struct pidff_usage *usage, s16 value)
 
 static void pidff_set_time(struct pidff_usage *usage, u16 time)
 {
-	u32 modified_time = pidff_rescale_time(time, usage->field);
-	usage->value[0] = pidff_clamp(modified_time, usage->field);
+	usage->value[0] = pidff_clamp(
+		pidff_rescale_time(time, usage->field), usage->field);
 }
 
 static void pidff_set_duration(struct pidff_usage *usage, u16 duration)
-- 
2.53.0

[PATCH 6.12.y 2/4] HID: pidff: Use ARRAY_SIZE macro instead of sizeof

[Sasha Levin]

From: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>

[ Upstream commit 8de2cef6d0de8cdddee8d653a18791525af26fad ]

Could lead to issues when arrays won't be 8 bit fields

Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Reviewed-by: Oleg Makarenko <oleg@makarenk.ooo>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Stable-dep-of: 67bb1074e3d2 ("HID: pidff: fix OOB write when hid->inputs is empty")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hid/usbhid/hid-pidff.c | 46 +++++++++++++++++-----------------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index 471dbc8fabc98..fe5462a19df38 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -158,20 +158,20 @@ struct pidff_usage {
 struct pidff_device {
 	struct hid_device *hid;
 
-	struct hid_report *reports[sizeof(pidff_reports)];
+	struct hid_report *reports[ARRAY_SIZE(pidff_reports)];
 
-	struct pidff_usage set_effect[sizeof(pidff_set_effect)];
-	struct pidff_usage set_envelope[sizeof(pidff_set_envelope)];
-	struct pidff_usage set_condition[sizeof(pidff_set_condition)];
-	struct pidff_usage set_periodic[sizeof(pidff_set_periodic)];
-	struct pidff_usage set_constant[sizeof(pidff_set_constant)];
-	struct pidff_usage set_ramp[sizeof(pidff_set_ramp)];
+	struct pidff_usage set_effect[ARRAY_SIZE(pidff_set_effect)];
+	struct pidff_usage set_envelope[ARRAY_SIZE(pidff_set_envelope)];
+	struct pidff_usage set_condition[ARRAY_SIZE(pidff_set_condition)];
+	struct pidff_usage set_periodic[ARRAY_SIZE(pidff_set_periodic)];
+	struct pidff_usage set_constant[ARRAY_SIZE(pidff_set_constant)];
+	struct pidff_usage set_ramp[ARRAY_SIZE(pidff_set_ramp)];
 
-	struct pidff_usage device_gain[sizeof(pidff_device_gain)];
-	struct pidff_usage block_load[sizeof(pidff_block_load)];
-	struct pidff_usage pool[sizeof(pidff_pool)];
-	struct pidff_usage effect_operation[sizeof(pidff_effect_operation)];
-	struct pidff_usage block_free[sizeof(pidff_block_free)];
+	struct pidff_usage device_gain[ARRAY_SIZE(pidff_device_gain)];
+	struct pidff_usage block_load[ARRAY_SIZE(pidff_block_load)];
+	struct pidff_usage pool[ARRAY_SIZE(pidff_pool)];
+	struct pidff_usage effect_operation[ARRAY_SIZE(pidff_effect_operation)];
+	struct pidff_usage block_free[ARRAY_SIZE(pidff_block_free)];
 
 	/*
 	 * Special field is a field that is not composed of
@@ -194,10 +194,10 @@ struct pidff_device {
 	/* Special field in effect_operation */
 	struct hid_field *effect_operation_status;
 
-	int control_id[sizeof(pidff_device_control)];
-	int type_id[sizeof(pidff_effect_types)];
-	int status_id[sizeof(pidff_block_load_status)];
-	int operation_id[sizeof(pidff_effect_operation_status)];
+	int control_id[ARRAY_SIZE(pidff_device_control)];
+	int type_id[ARRAY_SIZE(pidff_effect_types)];
+	int status_id[ARRAY_SIZE(pidff_block_load_status)];
+	int operation_id[ARRAY_SIZE(pidff_effect_operation_status)];
 
 	int pid_id[PID_EFFECTS_MAX];
 
@@ -642,7 +642,7 @@ static void pidff_set_device_control(struct pidff_device *pidff, int field)
 		hid_dbg(pidff->hid, "DEVICE_CONTROL is a bitmask\n");
 
 		/* Clear current bitmask */
-		for (i = 0; i < sizeof(pidff_device_control); i++) {
+		for (i = 0; i < ARRAY_SIZE(pidff_device_control); i++) {
 			index = pidff->control_id[i];
 			if (index < 1)
 				continue;
@@ -1002,7 +1002,7 @@ static int pidff_check_usage(int usage)
 {
 	int i;
 
-	for (i = 0; i < sizeof(pidff_reports); i++)
+	for (i = 0; i < ARRAY_SIZE(pidff_reports); i++)
 		if (usage == (HID_UP_PID | pidff_reports[i]))
 			return i;
 
@@ -1121,7 +1121,7 @@ static int pidff_find_special_keys(int *keys, struct hid_field *fld,
 
 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
 	pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
-		sizeof(pidff_ ## name))
+		ARRAY_SIZE(pidff_ ## name))
 
 /*
  * Find and check the special fields
@@ -1196,7 +1196,7 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 
 	if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
 				    block_load_status) !=
-			sizeof(pidff_block_load_status)) {
+			ARRAY_SIZE(pidff_block_load_status)) {
 		hid_err(pidff->hid,
 			"block load status identifiers not found\n");
 		return -1;
@@ -1204,7 +1204,7 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 
 	if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
 				    effect_operation_status) !=
-			sizeof(pidff_effect_operation_status)) {
+			ARRAY_SIZE(pidff_effect_operation_status)) {
 		hid_err(pidff->hid, "effect operation identifiers not found\n");
 		return -1;
 	}
@@ -1220,7 +1220,7 @@ static int pidff_find_effects(struct pidff_device *pidff,
 {
 	int i;
 
-	for (i = 0; i < sizeof(pidff_effect_types); i++) {
+	for (i = 0; i < ARRAY_SIZE(pidff_effect_types); i++) {
 		int pidff_type = pidff->type_id[i];
 
 		if (pidff->set_effect_type->usage[pidff_type].hid !=
@@ -1270,7 +1270,7 @@ static int pidff_find_effects(struct pidff_device *pidff,
 #define PIDFF_FIND_FIELDS(name, report, strict) \
 	pidff_find_fields(pidff->name, pidff_ ## name, \
 		pidff->reports[report], \
-		sizeof(pidff_ ## name), strict)
+		ARRAY_SIZE(pidff_ ## name), strict)
 
 /*
  * Fill and check the pidff_usages
-- 
2.53.0

[PATCH 6.12.y 3/4] HID: pidff: clang-format pass

[Sasha Levin]

From: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>

[ Upstream commit ae42428fb4e3d2eed344f0d6fcfa778bc8b8f80a ]

Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Stable-dep-of: 67bb1074e3d2 ("HID: pidff: fix OOB write when hid->inputs is empty")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hid/usbhid/hid-pidff.c | 55 ++++++++++++++++------------------
 1 file changed, 26 insertions(+), 29 deletions(-)

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index fe5462a19df38..72ed11e054665 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -9,12 +9,11 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include "hid-pidff.h"
+#include <linux/hid.h>
 #include <linux/input.h>
+#include <linux/minmax.h>
 #include <linux/slab.h>
 #include <linux/usb.h>
-#include <linux/hid.h>
-#include <linux/minmax.h>
-
 
 #define	PID_EFFECTS_MAX		64
 #define	PID_INFINITE		U16_MAX
@@ -285,7 +284,7 @@ static s32 pidff_clamp(s32 i, struct hid_field *field)
 static int pidff_rescale(int i, int max, struct hid_field *field)
 {
 	return i * (field->logical_maximum - field->logical_minimum) / max +
-		field->logical_minimum;
+	       field->logical_minimum;
 }
 
 /*
@@ -329,18 +328,18 @@ static void pidff_set_signed(struct pidff_usage *usage, s16 value)
 	else {
 		if (value < 0)
 			usage->value[0] =
-			    pidff_rescale(-value, -S16_MIN, usage->field);
+				pidff_rescale(-value, -S16_MIN, usage->field);
 		else
 			usage->value[0] =
-			    pidff_rescale(value, S16_MAX, usage->field);
+				pidff_rescale(value, S16_MAX, usage->field);
 	}
 	pr_debug("calculated from %d to %d\n", value, usage->value[0]);
 }
 
 static void pidff_set_time(struct pidff_usage *usage, u16 time)
 {
-	usage->value[0] = pidff_clamp(
-		pidff_rescale_time(time, usage->field), usage->field);
+	usage->value[0] = pidff_clamp(pidff_rescale_time(time, usage->field),
+				      usage->field);
 }
 
 static void pidff_set_duration(struct pidff_usage *usage, u16 duration)
@@ -463,11 +462,11 @@ static void pidff_set_effect_report(struct pidff_device *pidff,
 		pidff_get_effect_type_id(pidff, effect);
 
 	pidff_set_duration(&pidff->set_effect[PID_DURATION],
-		effect->replay.length);
+			   effect->replay.length);
 
 	pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
 	pidff_set_time(&pidff->set_effect[PID_TRIGGER_REPEAT_INT],
-			effect->trigger.interval);
+		       effect->trigger.interval);
 	pidff->set_effect[PID_GAIN].value[0] =
 		pidff->set_effect[PID_GAIN].field->logical_maximum;
 	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
@@ -477,10 +476,10 @@ static void pidff_set_effect_report(struct pidff_device *pidff,
 	/* Omit setting delay field if it's missing */
 	if (!(pidff->quirks & HID_PIDFF_QUIRK_MISSING_DELAY))
 		pidff_set_time(&pidff->set_effect[PID_START_DELAY],
-				effect->replay.delay);
+			       effect->replay.delay);
 
 	hid_hw_request(pidff->hid, pidff->reports[PID_SET_EFFECT],
-			HID_REQ_SET_REPORT);
+		       HID_REQ_SET_REPORT);
 }
 
 /*
@@ -510,10 +509,10 @@ static void pidff_set_periodic_report(struct pidff_device *pidff,
 			 effect->u.periodic.offset);
 	pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
 	pidff_set_time(&pidff->set_periodic[PID_PERIOD],
-			effect->u.periodic.period);
+		       effect->u.periodic.period);
 
 	hid_hw_request(pidff->hid, pidff->reports[PID_SET_PERIODIC],
-			HID_REQ_SET_REPORT);
+		       HID_REQ_SET_REPORT);
 }
 
 /*
@@ -560,7 +559,7 @@ static void pidff_set_condition_report(struct pidff_device *pidff,
 		pidff_set(&pidff->set_condition[PID_DEAD_BAND],
 			  effect->u.condition[i].deadband);
 		hid_hw_request(pidff->hid, pidff->reports[PID_SET_CONDITION],
-				HID_REQ_SET_REPORT);
+			       HID_REQ_SET_REPORT);
 	}
 }
 
@@ -623,7 +622,7 @@ static void pidff_set_gain_report(struct pidff_device *pidff, u16 gain)
 
 	pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
 	hid_hw_request(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
-			HID_REQ_SET_REPORT);
+		       HID_REQ_SET_REPORT);
 }
 
 /*
@@ -717,21 +716,19 @@ static void pidff_fetch_pool(struct pidff_device *pidff)
  */
 static int pidff_request_effect_upload(struct pidff_device *pidff, int efnum)
 {
-	int j;
-
 	pidff->create_new_effect_type->value[0] = efnum;
 	hid_hw_request(pidff->hid, pidff->reports[PID_CREATE_NEW_EFFECT],
-			HID_REQ_SET_REPORT);
+		       HID_REQ_SET_REPORT);
 	hid_dbg(pidff->hid, "create_new_effect sent, type: %d\n", efnum);
 
 	pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
 	pidff->block_load_status->value[0] = 0;
 	hid_hw_wait(pidff->hid);
 
-	for (j = 0; j < 60; j++) {
+	for (int i = 0; i < 60; i++) {
 		hid_dbg(pidff->hid, "pid_block_load requested\n");
 		hid_hw_request(pidff->hid, pidff->reports[PID_BLOCK_LOAD],
-				HID_REQ_GET_REPORT);
+			       HID_REQ_GET_REPORT);
 		hid_hw_wait(pidff->hid);
 		if (pidff->block_load_status->value[0] ==
 		    pidff->status_id[PID_BLOCK_LOAD_SUCCESS]) {
@@ -808,8 +805,8 @@ static int pidff_erase_effect(struct input_dev *dev, int effect_id)
 	struct pidff_device *pidff = dev->ff->private;
 	int pid_id = pidff->pid_id[effect_id];
 
-	hid_dbg(pidff->hid, "starting to erase %d/%d\n",
-		effect_id, pidff->pid_id[effect_id]);
+	hid_dbg(pidff->hid, "starting to erase %d/%d\n", effect_id,
+		pidff->pid_id[effect_id]);
 
 	/*
 	 * Wait for the queue to clear. We do not want
@@ -929,7 +926,7 @@ static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
 		pidff->set_effect[PID_START_DELAY].value[0] = 0;
 
 	hid_hw_request(pidff->hid, pidff->reports[PID_SET_EFFECT],
-			HID_REQ_SET_REPORT);
+		       HID_REQ_SET_REPORT);
 }
 
 /*
@@ -1196,7 +1193,7 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 
 	if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
 				    block_load_status) !=
-			ARRAY_SIZE(pidff_block_load_status)) {
+	    ARRAY_SIZE(pidff_block_load_status)) {
 		hid_err(pidff->hid,
 			"block load status identifiers not found\n");
 		return -1;
@@ -1204,7 +1201,7 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 
 	if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
 				    effect_operation_status) !=
-			ARRAY_SIZE(pidff_effect_operation_status)) {
+	    ARRAY_SIZE(pidff_effect_operation_status)) {
 		hid_err(pidff->hid, "effect operation identifiers not found\n");
 		return -1;
 	}
@@ -1408,8 +1405,8 @@ static int pidff_check_autocenter(struct pidff_device *pidff,
 int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks)
 {
 	struct pidff_device *pidff;
-	struct hid_input *hidinput = list_entry(hid->inputs.next,
-						struct hid_input, list);
+	struct hid_input *hidinput =
+		list_entry(hid->inputs.next, struct hid_input, list);
 	struct input_dev *dev = hidinput->input;
 	struct ff_device *ff;
 	int max_effects;
@@ -1496,7 +1493,7 @@ int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks)
 
 	return 0;
 
- fail:
+fail:
 	hid_device_io_stop(hid);
 
 	kfree(pidff);
-- 
2.53.0

[PATCH 6.12.y 4/4] HID: pidff: fix OOB write when hid->inputs is empty

[Sasha Levin]

From: Baul Lee <baul.lee@xbow.com>

[ Upstream commit 67bb1074e3d2d12fa059a9cc707e89398a4e4704 ]

hid_pidff_init_with_quirks() derives its input_dev from

	list_entry(hid->inputs.next, struct hid_input, list)

without first checking that hid->inputs is non-empty.  The list member
of struct hid_input is at offset 0, so on an empty list list_entry()
yields &hid->inputs itself and the following hidinput->input load reads
an unrelated member of struct hid_device.  dev is then a type-confused
pointer, and force-feedback init writes through it: each
set_bit(FF_*, dev->ffbit) stores 8 bytes at dev + 192, past the end of
the object dev actually aliases, and input_ff_create() adds further
writes of a heap pointer and two function pointers.

Until hid-universal-pidff the only caller was hid_pidff_init() from
usbhid, which runs under HID_CLAIMED_INPUT and therefore always has at
least one hid_input.  universal_pidff_probe() starts the device with
HID_CONNECT_DEFAULT & ~HID_CONNECT_FF and then calls
hid_pidff_init_with_quirks() directly whenever the descriptor carries a
PID usage page, bypassing that gate.  A report descriptor whose only
application collection is on HID_UP_PID leaves hid->inputs empty while
hid_connect() still succeeds through the hidraw claim, so probe reaches
the unguarded list_entry().

The write happens in the USB probe path, on the hotplug workqueue, so
plugging in a malicious device is enough to trigger it; no attacker
software and no logged-in user are required.  KASAN reports an 8-byte
out-of-bounds write in hid_pidff_init_with_quirks() reached from
universal_pidff_probe().

Check for an empty list before deriving dev and return -ENODEV, as the
other HID force-feedback drivers already do.  universal_pidff_probe()
propagates the error and unwinds.

Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>

Fixes: f06bf8d94fff ("HID: Add hid-universal-pidff driver and supported device ids")
Reported-by: Federico Kirschbaum <federico.kirschbaum@xbow.com>
Reported-by: Baul Lee <baul.lee@xbow.com>
Cc: stable@vger.kernel.org
Signed-off-by: Baul Lee <baul.lee@xbow.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hid/usbhid/hid-pidff.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index 72ed11e054665..751570de7f52a 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -1405,13 +1405,20 @@ static int pidff_check_autocenter(struct pidff_device *pidff,
 int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks)
 {
 	struct pidff_device *pidff;
-	struct hid_input *hidinput =
-		list_entry(hid->inputs.next, struct hid_input, list);
-	struct input_dev *dev = hidinput->input;
+	struct hid_input *hidinput;
+	struct input_dev *dev;
 	struct ff_device *ff;
 	int max_effects;
 	int error;
 
+	if (list_empty(&hid->inputs)) {
+		hid_err(hid, "no inputs found\n");
+		return -ENODEV;
+	}
+
+	hidinput = list_first_entry(&hid->inputs, struct hid_input, list);
+	dev = hidinput->input;
+
 	hid_dbg(hid, "starting pid init\n");
 
 	if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
-- 
2.53.0