KASAN: slab-out-of-bounds Write in ga_probe

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: f0df5c1b usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=14045831600000
kernel config: https://syzkaller.appspot.com/x/.config?x=5c6633fa4ed00be5
dashboard link: https://syzkaller.appspot.com/bug?extid=403741a091bf41d4ae79
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13c1e62d600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=166a3a95600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+403741...@syzkaller.appspotmail.com

usb 1-1: config 0 interface 0 altsetting 0 has 1 endpoint descriptor,
different from the interface descriptor's value: 9
usb 1-1: New USB device found, idVendor=0e8f, idProduct=0012, bcdDevice=
0.00
usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
usb 1-1: config 0 descriptor??
greenasia 0003:0E8F:0012.0001: unknown main item tag 0x0
greenasia 0003:0E8F:0012.0001: hidraw0: USB HID v0.00 Device [HID
0e8f:0012] on usb-dummy_hcd.0-1/input0
==================================================================
BUG: KASAN: slab-out-of-bounds in set_bit
include/asm-generic/bitops-instrumented.h:28 [inline]
BUG: KASAN: slab-out-of-bounds in gaff_init drivers/hid/hid-gaff.c:97
[inline]
BUG: KASAN: slab-out-of-bounds in ga_probe+0x1fd/0x6f0
drivers/hid/hid-gaff.c:146
Write of size 8 at addr ffff8881d9acafc0 by task kworker/1:1/78

CPU: 1 PID: 78 Comm: kworker/1:1 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x6a/0x32c mm/kasan/report.c:351
__kasan_report.cold+0x1a/0x33 mm/kasan/report.c:482
kasan_report+0xe/0x12 mm/kasan/common.c:618
check_memory_region_inline mm/kasan/generic.c:185 [inline]
check_memory_region+0x128/0x190 mm/kasan/generic.c:192
set_bit include/asm-generic/bitops-instrumented.h:28 [inline]
gaff_init drivers/hid/hid-gaff.c:97 [inline]
ga_probe+0x1fd/0x6f0 drivers/hid/hid-gaff.c:146
hid_device_probe+0x2be/0x3f0 drivers/hid/hid-core.c:2209
really_probe+0x281/0x6d0 drivers/base/dd.c:548
driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721
__device_attach_driver+0x


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

[Alan Stern]

The driver assumes that the device contains an input.

Alan Stern

https://github.com/google/kasan.git f0df5c1b

drivers/hid/hid-gaff.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

Index: usb-devel/drivers/hid/hid-gaff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-gaff.c
+++ usb-devel/drivers/hid/hid-gaff.c
@@ -64,14 +64,20 @@ static int gaff_init(struct hid_device *
{
struct gaff_device *gaff;
struct hid_report *report;
- struct hid_input *hidinput = list_entry(hid->inputs.next,
- struct hid_input, list);
+ struct hid_input *hidinput;
struct list_head *report_list =
&hid->report_enum[HID_OUTPUT_REPORT].report_list;
struct list_head *report_ptr = report_list;
- struct input_dev *dev = hidinput->input;
+ struct input_dev *dev;
int error;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+
if (list_empty(report_list)) {
hid_err(hid, "no output reports found\n");
return -ENODEV;

[Andrey Konovalov]

You've forgotten "syz test" here :)

#syz test: https://github.com/google/kasan.git f0df5c1b

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger
crash:

Reported-and-tested-by:
syzbot+403741...@syzkaller.appspotmail.com

Tested on:

commit: f0df5c1b usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git

kernel config: https://syzkaller.appspot.com/x/.config?x=5c6633fa4ed00be5
dashboard link: https://syzkaller.appspot.com/bug?extid=403741a091bf41d4ae79
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

patch: https://syzkaller.appspot.com/x/patch.diff?x=131651c9600000

Note: testing is done by a robot and is best-effort only.

[Andrey Konovalov]

On Tue, Sep 17, 2019 at 8:24 PM Alan Stern <st...@rowland.harvard.edu> wrote:
>

BTW, these two reports look fairly similar:

https://syzkaller.appspot.com/bug?extid=94e2b9e9c7d1dd332345
https://syzkaller.appspot.com/bug?extid=1e86e2ccce227cca899b

[Alan Stern]

Indeed they do. I don't have time to patch them now; maybe next week.
Unless you or someone else would like to do it first... :-)

Essentially the same fix should work for each of these -- looks like
they were written using copy-and-paste. In fact, a quick grep through
drivers/hid/*.c shows about 9 of them with the same suspect
initialization code for hidinput.

Alan Stern

[Alan Stern]

The syzbot fuzzer found a slab-out-of-bounds write bug in the hid-gaff
driver. The problem is caused by the driver's assumption that the
device must have an input report. While this will be true for all
normal HID input devices, a suitably malicious device can violate the
assumption.

The same assumption is present in over a dozen other HID drivers.
This patch fixes them by checking that the list of hid_inputs for the
hid_device is nonempty before allowing it to be used.

Reported-and-tested-by: syzbot+403741...@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <st...@rowland.harvard.edu>
CC: <sta...@vger.kernel.org>

---

[as1921]


drivers/hid/hid-axff.c | 11 +++++++++--
drivers/hid/hid-dr.c | 12 +++++++++---
drivers/hid/hid-emsff.c | 12 +++++++++---
drivers/hid/hid-gaff.c | 12 +++++++++---
drivers/hid/hid-holtekff.c | 12 +++++++++---
drivers/hid/hid-lg2ff.c | 12 +++++++++---
drivers/hid/hid-lg3ff.c | 11 +++++++++--
drivers/hid/hid-lg4ff.c | 11 +++++++++--
drivers/hid/hid-lgff.c | 11 +++++++++--
drivers/hid/hid-logitech-hidpp.c | 11 +++++++++--
drivers/hid/hid-microsoft.c | 12 +++++++++---
drivers/hid/hid-sony.c | 12 +++++++++---
drivers/hid/hid-tmff.c | 12 +++++++++---
drivers/hid/hid-zpff.c | 12 +++++++++---
14 files changed, 126 insertions(+), 37 deletions(-)

Index: usb-devel/drivers/hid/hid-axff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-axff.c
+++ usb-devel/drivers/hid/hid-axff.c
@@ -63,13 +63,20 @@ static int axff_init(struct hid_device *
{
struct axff_device *axff;
struct hid_report *report;
- struct hid_input *hidinput = list_first_entry(&hid->inputs, struct hid_input, list);

+ struct hid_input *hidinput;
struct list_head *report_list =&hid->report_enum[HID_OUTPUT_REPORT].report_list;

- struct input_dev *dev = hidinput->input;
+ struct input_dev *dev;

int field_count = 0;
int i, j;

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;
+
if (list_empty(report_list)) {
hid_err(hid, "no output reports found\n");
return -ENODEV;

Index: usb-devel/drivers/hid/hid-dr.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-dr.c
+++ usb-devel/drivers/hid/hid-dr.c
@@ -75,13 +75,19 @@ static int drff_init(struct hid_device *
{
struct drff_device *drff;
struct hid_report *report;
- struct hid_input *hidinput = list_first_entry(&hid->inputs,

- struct hid_input, list);
+ struct hid_input *hidinput;
struct list_head *report_list =
&hid->report_enum[HID_OUTPUT_REPORT].report_list;

- struct input_dev *dev = hidinput->input;
+ struct input_dev *dev;
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;
+
if (list_empty(report_list)) {
hid_err(hid, "no output reports found\n");
return -ENODEV;

Index: usb-devel/drivers/hid/hid-emsff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-emsff.c
+++ usb-devel/drivers/hid/hid-emsff.c
@@ -47,13 +47,19 @@ static int emsff_init(struct hid_device
{
struct emsff_device *emsff;
struct hid_report *report;
- struct hid_input *hidinput = list_first_entry(&hid->inputs,

- struct hid_input, list);
+ struct hid_input *hidinput;
struct list_head *report_list =
&hid->report_enum[HID_OUTPUT_REPORT].report_list;

- struct input_dev *dev = hidinput->input;
+ struct input_dev *dev;
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;
+
if (list_empty(report_list)) {
hid_err(hid, "no output reports found\n");
return -ENODEV;

Index: usb-devel/drivers/hid/hid-holtekff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-holtekff.c
+++ usb-devel/drivers/hid/hid-holtekff.c
@@ -124,13 +124,19 @@ static int holtekff_init(struct hid_devi
{
struct holtekff_device *holtekff;

struct hid_report *report;
- struct hid_input *hidinput = list_entry(hid->inputs.next,
- struct hid_input, list);
+ struct hid_input *hidinput;
struct list_head *report_list =
&hid->report_enum[HID_OUTPUT_REPORT].report_list;

- struct input_dev *dev = hidinput->input;
+ struct input_dev *dev;
int error;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+
if (list_empty(report_list)) {

hid_err(hid, "no output report found\n");
return -ENODEV;
Index: usb-devel/drivers/hid/hid-lg2ff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-lg2ff.c
+++ usb-devel/drivers/hid/hid-lg2ff.c
@@ -50,11 +50,17 @@ int lg2ff_init(struct hid_device *hid)
{
struct lg2ff_device *lg2ff;

struct hid_report *report;
- 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;
int error;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+

/* Check that the report looks ok */
report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7);
if (!report)
Index: usb-devel/drivers/hid/hid-lg3ff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-lg3ff.c
+++ usb-devel/drivers/hid/hid-lg3ff.c
@@ -117,12 +117,19 @@ static const signed short ff3_joystick_a

int lg3ff_init(struct hid_device *hid)
{
- 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;
const signed short *ff_bits = ff3_joystick_ac;
int error;
int i;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+

/* Check that the report looks ok */
if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 35))
return -ENODEV;
Index: usb-devel/drivers/hid/hid-lg4ff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-lg4ff.c
+++ usb-devel/drivers/hid/hid-lg4ff.c
@@ -1253,8 +1253,8 @@ static int lg4ff_handle_multimode_wheel(

int lg4ff_init(struct hid_device *hid)
{
- 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 list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;

struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
const struct usb_device_descriptor *udesc = &(hid_to_usb_dev(hid)->descriptor);
@@ -1266,6 +1266,13 @@ int lg4ff_init(struct hid_device *hid)
int mmode_ret, mmode_idx = -1;
u16 real_product_id;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+

/* Check that the report looks ok */
if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
return -1;
Index: usb-devel/drivers/hid/hid-lgff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-lgff.c
+++ usb-devel/drivers/hid/hid-lgff.c
@@ -115,12 +115,19 @@ static void hid_lgff_set_autocenter(stru

int lgff_init(struct hid_device* hid)
{
- 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;
const signed short *ff_bits = ff_joystick;
int error;
int i;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+

/* Check that the report looks ok */
if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
return -ENODEV;
Index: usb-devel/drivers/hid/hid-logitech-hidpp.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-logitech-hidpp.c
+++ usb-devel/drivers/hid/hid-logitech-hidpp.c
@@ -2084,8 +2084,8 @@ static void hidpp_ff_destroy(struct ff_d
static int hidpp_ff_init(struct hidpp_device *hidpp, u8 feature_index)
{
struct hid_device *hid = hidpp->hid_dev;
- 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;
const struct usb_device_descriptor *udesc = &(hid_to_usb_dev(hid)->descriptor);
const u16 bcdDevice = le16_to_cpu(udesc->bcdDevice);
struct ff_device *ff;
@@ -2094,6 +2094,13 @@ static int hidpp_ff_init(struct hidpp_de
int error, j, num_slots;
u8 version;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+

if (!dev) {
hid_err(hid, "Struct input_dev not set!\n");
return -EINVAL;
Index: usb-devel/drivers/hid/hid-microsoft.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-microsoft.c
+++ usb-devel/drivers/hid/hid-microsoft.c
@@ -328,11 +328,17 @@ static int ms_play_effect(struct input_d

static int ms_init_ff(struct hid_device *hdev)
{
- struct hid_input *hidinput = list_entry(hdev->inputs.next,
- struct hid_input, list);
- struct input_dev *input_dev = hidinput->input;
+ struct hid_input *hidinput;
+ struct input_dev *input_dev;
struct ms_data *ms = hid_get_drvdata(hdev);

+ if (list_empty(&hdev->inputs)) {
+ hid_err(hdev, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hdev->inputs.next, struct hid_input, list);
+ input_dev = hidinput->input;
+
if (!(ms->quirks & MS_QUIRK_FF))
return 0;

Index: usb-devel/drivers/hid/hid-sony.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-sony.c
+++ usb-devel/drivers/hid/hid-sony.c
@@ -2250,9 +2250,15 @@ static int sony_play_effect(struct input

static int sony_init_ff(struct sony_sc *sc)
{
- struct hid_input *hidinput = list_entry(sc->hdev->inputs.next,
- struct hid_input, list);
- struct input_dev *input_dev = hidinput->input;
+ struct hid_input *hidinput;
+ struct input_dev *input_dev;
+
+ if (list_empty(&sc->hdev->inputs)) {
+ hid_err(sc->hdev, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(sc->hdev->inputs.next, struct hid_input, list);
+ input_dev = hidinput->input;

input_set_capability(input_dev, EV_FF, FF_RUMBLE);
return input_ff_create_memless(input_dev, NULL, sony_play_effect);
Index: usb-devel/drivers/hid/hid-tmff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-tmff.c
+++ usb-devel/drivers/hid/hid-tmff.c
@@ -114,12 +114,18 @@ static int tmff_init(struct hid_device *
struct tmff_device *tmff;
struct hid_report *report;
struct list_head *report_list;

- struct hid_input *hidinput = list_entry(hid->inputs.next,
- struct hid_input, list);

- struct input_dev *input_dev = hidinput->input;
+ struct hid_input *hidinput;
+ struct input_dev *input_dev;
int error;
int i;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);

+ input_dev = hidinput->input;
+
tmff = kzalloc(sizeof(struct tmff_device), GFP_KERNEL);
if (!tmff)
return -ENOMEM;
Index: usb-devel/drivers/hid/hid-zpff.c
===================================================================
--- usb-devel.orig/drivers/hid/hid-zpff.c
+++ usb-devel/drivers/hid/hid-zpff.c
@@ -54,11 +54,17 @@ static int zpff_init(struct hid_device *
{
struct zpff_device *zpff;

struct hid_report *report;
- 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;
int i, error;

+ if (list_empty(&hid->inputs)) {
+ hid_err(hid, "no inputs found\n");
+ return -ENODEV;
+ }
+ hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+ dev = hidinput->input;
+

for (i = 0; i < 4; i++) {
report = hid_validate_values(hid, HID_OUTPUT_REPORT, 0, i, 1);
if (!report)

[Alan Stern]

On Thu, 19 Sep 2019, Andrey Konovalov wrote:

> BTW, these two reports look fairly similar:
>
> https://syzkaller.appspot.com/bug?extid=94e2b9e9c7d1dd332345
> https://syzkaller.appspot.com/bug?extid=1e86e2ccce227cca899b

#syz dup: KASAN: slab-out-of-bounds Write in ga_probe

Alan Stern

[Alan Stern]

On Thu, 19 Sep 2019, Andrey Konovalov wrote:

> BTW, these two reports look fairly similar:
>
> https://syzkaller.appspot.com/bug?extid=94e2b9e9c7d1dd332345
> https://syzkaller.appspot.com/bug?extid=1e86e2ccce227cca899b

[Benjamin Tissoires]

On Thu, Oct 3, 2019 at 2:54 PM Alan Stern <st...@rowland.harvard.edu> wrote:
>
> The syzbot fuzzer found a slab-out-of-bounds write bug in the hid-gaff
> driver. The problem is caused by the driver's assumption that the
> device must have an input report. While this will be true for all
> normal HID input devices, a suitably malicious device can violate the
> assumption.
>
> The same assumption is present in over a dozen other HID drivers.
> This patch fixes them by checking that the list of hid_inputs for the
> hid_device is nonempty before allowing it to be used.
>
> Reported-and-tested-by: syzbot+403741...@syzkaller.appspotmail.com
> Signed-off-by: Alan Stern <st...@rowland.harvard.edu>
> CC: <sta...@vger.kernel.org>

Thanks Alan pushed to for-5.4/upstream-fixes

Cheers,
Benjamin