2019-06-03 17:55:57

by syzbot

[permalink] [raw]
Subject: KMSAN: uninit-value in ax88772_bind

Hello,

syzbot found the following crash on:

HEAD commit: f75e4cfe kmsan: use kmsan_handle_urb() in urb.c
git tree: kmsan
console output: https://syzkaller.appspot.com/x/log.txt?x=136d720ea00000
kernel config: https://syzkaller.appspot.com/x/.config?x=602468164ccdc30a
dashboard link: https://syzkaller.appspot.com/bug?extid=8a3fc6674bbc3978ed4e
compiler: clang version 9.0.0 (/home/glider/llvm/clang
06d00afa61eef8f7f501ebdb4e8612ea43ec2d78)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12788316a00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=120359aaa00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email protected]

==================================================================
BUG: KMSAN: uninit-value in is_valid_ether_addr
include/linux/etherdevice.h:200 [inline]
BUG: KMSAN: uninit-value in asix_set_netdev_dev_addr
drivers/net/usb/asix_devices.c:73 [inline]
BUG: KMSAN: uninit-value in ax88772_bind+0x93d/0x11e0
drivers/net/usb/asix_devices.c:724
CPU: 0 PID: 3348 Comm: kworker/0:2 Not tainted 5.1.0+ #1
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+0x191/0x1f0 lib/dump_stack.c:113
kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
__msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
is_valid_ether_addr include/linux/etherdevice.h:200 [inline]
asix_set_netdev_dev_addr drivers/net/usb/asix_devices.c:73 [inline]
ax88772_bind+0x93d/0x11e0 drivers/net/usb/asix_devices.c:724
usbnet_probe+0x10f5/0x3940 drivers/net/usb/usbnet.c:1728
usb_probe_interface+0xd66/0x1320 drivers/usb/core/driver.c:361
really_probe+0xdae/0x1d80 drivers/base/dd.c:513
driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x454/0x730 drivers/base/dd.c:844
device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
bus_probe_device+0x137/0x390 drivers/base/bus.c:514
device_add+0x288d/0x30e0 drivers/base/core.c:2106
usb_set_configuration+0x30dc/0x3750 drivers/usb/core/message.c:2027
generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
usb_probe_device+0x14c/0x200 drivers/usb/core/driver.c:266
really_probe+0xdae/0x1d80 drivers/base/dd.c:513
driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x454/0x730 drivers/base/dd.c:844
device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
bus_probe_device+0x137/0x390 drivers/base/bus.c:514
device_add+0x288d/0x30e0 drivers/base/core.c:2106
usb_new_device+0x23e5/0x2ff0 drivers/usb/core/hub.c:2534
hub_port_connect drivers/usb/core/hub.c:5089 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
port_event drivers/usb/core/hub.c:5350 [inline]
hub_event+0x48d1/0x7290 drivers/usb/core/hub.c:5432
process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x189c/0x2460 kernel/workqueue.c:2417
kthread+0x4b5/0x4f0 kernel/kthread.c:254
ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355


---
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 [email protected].

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


2019-07-01 00:45:36

by Phong Tran

[permalink] [raw]
Subject: [PATCH] net: usb: asix: init MAC address buffers

This is for fixing bug KMSAN: uninit-value in ax88772_bind

Tested by
https://groups.google.com/d/msg/syzkaller-bugs/aFQurGotng4/cFe9nxMCCwAJ

Reported-by: [email protected]

syzbot found the following crash on:

HEAD commit: f75e4cfe kmsan: use kmsan_handle_urb() in urb.c
git tree: kmsan
console output: https://syzkaller.appspot.com/x/log.txt?x=136d720ea00000
kernel config:
https://syzkaller.appspot.com/x/.config?x=602468164ccdc30a
dashboard link:
https://syzkaller.appspot.com/bug?extid=8a3fc6674bbc3978ed4e
compiler: clang version 9.0.0 (/home/glider/llvm/clang
06d00afa61eef8f7f501ebdb4e8612ea43ec2d78)
syz repro:
https://syzkaller.appspot.com/x/repro.syz?x=12788316a00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=120359aaa00000

==================================================================
BUG: KMSAN: uninit-value in is_valid_ether_addr
include/linux/etherdevice.h:200 [inline]
BUG: KMSAN: uninit-value in asix_set_netdev_dev_addr
drivers/net/usb/asix_devices.c:73 [inline]
BUG: KMSAN: uninit-value in ax88772_bind+0x93d/0x11e0
drivers/net/usb/asix_devices.c:724
CPU: 0 PID: 3348 Comm: kworker/0:2 Not tainted 5.1.0+ #1
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+0x191/0x1f0 lib/dump_stack.c:113
kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
__msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
is_valid_ether_addr include/linux/etherdevice.h:200 [inline]
asix_set_netdev_dev_addr drivers/net/usb/asix_devices.c:73 [inline]
ax88772_bind+0x93d/0x11e0 drivers/net/usb/asix_devices.c:724
usbnet_probe+0x10f5/0x3940 drivers/net/usb/usbnet.c:1728
usb_probe_interface+0xd66/0x1320 drivers/usb/core/driver.c:361
really_probe+0xdae/0x1d80 drivers/base/dd.c:513
driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x454/0x730 drivers/base/dd.c:844
device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
bus_probe_device+0x137/0x390 drivers/base/bus.c:514
device_add+0x288d/0x30e0 drivers/base/core.c:2106
usb_set_configuration+0x30dc/0x3750 drivers/usb/core/message.c:2027
generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
usb_probe_device+0x14c/0x200 drivers/usb/core/driver.c:266
really_probe+0xdae/0x1d80 drivers/base/dd.c:513
driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x454/0x730 drivers/base/dd.c:844
device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
bus_probe_device+0x137/0x390 drivers/base/bus.c:514
device_add+0x288d/0x30e0 drivers/base/core.c:2106
usb_new_device+0x23e5/0x2ff0 drivers/usb/core/hub.c:2534
hub_port_connect drivers/usb/core/hub.c:5089 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
port_event drivers/usb/core/hub.c:5350 [inline]
hub_event+0x48d1/0x7290 drivers/usb/core/hub.c:5432
process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x189c/0x2460 kernel/workqueue.c:2417
kthread+0x4b5/0x4f0 kernel/kthread.c:254
ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Signed-off-by: Phong Tran <[email protected]>
---
drivers/net/usb/asix_devices.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index c9bc96310ed4..f514d19316b1 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -230,6 +230,7 @@ static int ax88172_bind(struct usbnet *dev, struct usb_interface *intf)
int i;
unsigned long gpio_bits = dev->driver_info->data;

+ memset(buf, 0, sizeof(buf));
usbnet_get_endpoints(dev,intf);

/* Toggle the GPIOs in a manufacturer/model specific way */
@@ -681,6 +682,7 @@ static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf)
u32 phyid;
struct asix_common_private *priv;

+ memset(buf, 0, sizeof(buf));
usbnet_get_endpoints(dev, intf);

/* Maybe the boot loader passed the MAC address via device tree */
@@ -1063,6 +1065,7 @@ static int ax88178_bind(struct usbnet *dev, struct usb_interface *intf)
int ret;
u8 buf[ETH_ALEN];

+ memset(buf, 0, sizeof(buf));
usbnet_get_endpoints(dev,intf);

/* Get the MAC address */
--
2.11.0

2019-07-01 16:14:35

by Dan Williams

[permalink] [raw]
Subject: Re: [PATCH] net: usb: asix: init MAC address buffers

On Mon, 2019-07-01 at 06:45 +0700, Phong Tran wrote:
> This is for fixing bug KMSAN: uninit-value in ax88772_bind
>
> Tested by
> https://groups.google.com/d/msg/syzkaller-bugs/aFQurGotng4/cFe9nxMCCwAJ
>
> Reported-by: [email protected]
>
> syzbot found the following crash on:
>
> HEAD commit: f75e4cfe kmsan: use kmsan_handle_urb() in urb.c
> git tree: kmsan
> console output:
> https://syzkaller.appspot.com/x/log.txt?x=136d720ea00000
> kernel config:
> https://syzkaller.appspot.com/x/.config?x=602468164ccdc30a
> dashboard link:
> https://syzkaller.appspot.com/bug?extid=8a3fc6674bbc3978ed4e
> compiler: clang version 9.0.0 (/home/glider/llvm/clang
> 06d00afa61eef8f7f501ebdb4e8612ea43ec2d78)
> syz repro:
> https://syzkaller.appspot.com/x/repro.syz?x=12788316a00000
> C reproducer:
> https://syzkaller.appspot.com/x/repro.c?x=120359aaa00000
>
> ==================================================================
> BUG: KMSAN: uninit-value in is_valid_ether_addr
> include/linux/etherdevice.h:200 [inline]
> BUG: KMSAN: uninit-value in asix_set_netdev_dev_addr
> drivers/net/usb/asix_devices.c:73 [inline]
> BUG: KMSAN: uninit-value in ax88772_bind+0x93d/0x11e0
> drivers/net/usb/asix_devices.c:724
> CPU: 0 PID: 3348 Comm: kworker/0:2 Not tainted 5.1.0+ #1
> 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+0x191/0x1f0 lib/dump_stack.c:113
> kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
> __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
> is_valid_ether_addr include/linux/etherdevice.h:200 [inline]
> asix_set_netdev_dev_addr drivers/net/usb/asix_devices.c:73 [inline]
> ax88772_bind+0x93d/0x11e0 drivers/net/usb/asix_devices.c:724
> usbnet_probe+0x10f5/0x3940 drivers/net/usb/usbnet.c:1728
> usb_probe_interface+0xd66/0x1320 drivers/usb/core/driver.c:361
> really_probe+0xdae/0x1d80 drivers/base/dd.c:513
> driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
> __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
> bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
> __device_attach+0x454/0x730 drivers/base/dd.c:844
> device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
> bus_probe_device+0x137/0x390 drivers/base/bus.c:514
> device_add+0x288d/0x30e0 drivers/base/core.c:2106
> usb_set_configuration+0x30dc/0x3750 drivers/usb/core/message.c:2027
> generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
> usb_probe_device+0x14c/0x200 drivers/usb/core/driver.c:266
> really_probe+0xdae/0x1d80 drivers/base/dd.c:513
> driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
> __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
> bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
> __device_attach+0x454/0x730 drivers/base/dd.c:844
> device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
> bus_probe_device+0x137/0x390 drivers/base/bus.c:514
> device_add+0x288d/0x30e0 drivers/base/core.c:2106
> usb_new_device+0x23e5/0x2ff0 drivers/usb/core/hub.c:2534
> hub_port_connect drivers/usb/core/hub.c:5089 [inline]
> hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
> port_event drivers/usb/core/hub.c:5350 [inline]
> hub_event+0x48d1/0x7290 drivers/usb/core/hub.c:5432
> process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
> process_scheduled_works kernel/workqueue.c:2331 [inline]
> worker_thread+0x189c/0x2460 kernel/workqueue.c:2417
> kthread+0x4b5/0x4f0 kernel/kthread.c:254
> ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355
>
> Signed-off-by: Phong Tran <[email protected]>
> ---
> drivers/net/usb/asix_devices.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/net/usb/asix_devices.c
> b/drivers/net/usb/asix_devices.c
> index c9bc96310ed4..f514d19316b1 100644
> --- a/drivers/net/usb/asix_devices.c
> +++ b/drivers/net/usb/asix_devices.c
> @@ -230,6 +230,7 @@ static int ax88172_bind(struct usbnet *dev,
> struct usb_interface *intf)
> int i;
> unsigned long gpio_bits = dev->driver_info->data;
>
> + memset(buf, 0, sizeof(buf));

For array variables defined in the function itself, isn't this usually
done with:

int ret = 0;
- u8 buf[ETH_ALEN];
+ u8 buf[ETH_ALEN] = {0};
int i;
unsigned long gpio_bits = dev->driver_info->data;

eg make the compiler do it (though maybe it's smart enough to elide the
memset, I don't know). See drivers/net/ethernet/intel/igb/e1000_mac.c
for an example.

Dan

> usbnet_get_endpoints(dev,intf);
>
> /* Toggle the GPIOs in a manufacturer/model specific way */
> @@ -681,6 +682,7 @@ static int ax88772_bind(struct usbnet *dev,
> struct usb_interface *intf)
> u32 phyid;
> struct asix_common_private *priv;
>
> + memset(buf, 0, sizeof(buf));
> usbnet_get_endpoints(dev, intf);
>
> /* Maybe the boot loader passed the MAC address via device tree
> */
> @@ -1063,6 +1065,7 @@ static int ax88178_bind(struct usbnet *dev,
> struct usb_interface *intf)
> int ret;
> u8 buf[ETH_ALEN];
>
> + memset(buf, 0, sizeof(buf));
> usbnet_get_endpoints(dev,intf);
>
> /* Get the MAC address */

2019-07-02 00:03:52

by Phong Tran

[permalink] [raw]
Subject: Re: [PATCH] net: usb: asix: init MAC address buffers

Hello Dan,

On Mon, Jul 1, 2019 at 10:30 PM Dan Williams <[email protected]> wrote:
>
> On Mon, 2019-07-01 at 06:45 +0700, Phong Tran wrote:
> > This is for fixing bug KMSAN: uninit-value in ax88772_bind
> >
> > Tested by
> > https://groups.google.com/d/msg/syzkaller-bugs/aFQurGotng4/cFe9nxMCCwAJ
> >
> > Reported-by: [email protected]
> >
> > syzbot found the following crash on:
> >
> > HEAD commit: f75e4cfe kmsan: use kmsan_handle_urb() in urb.c
> > git tree: kmsan
> > console output:
> > https://syzkaller.appspot.com/x/log.txt?x=136d720ea00000
> > kernel config:
> > https://syzkaller.appspot.com/x/.config?x=602468164ccdc30a
> > dashboard link:
> > https://syzkaller.appspot.com/bug?extid=8a3fc6674bbc3978ed4e
> > compiler: clang version 9.0.0 (/home/glider/llvm/clang
> > 06d00afa61eef8f7f501ebdb4e8612ea43ec2d78)
> > syz repro:
> > https://syzkaller.appspot.com/x/repro.syz?x=12788316a00000
> > C reproducer:
> > https://syzkaller.appspot.com/x/repro.c?x=120359aaa00000
> >
> > ==================================================================
> > BUG: KMSAN: uninit-value in is_valid_ether_addr
> > include/linux/etherdevice.h:200 [inline]
> > BUG: KMSAN: uninit-value in asix_set_netdev_dev_addr
> > drivers/net/usb/asix_devices.c:73 [inline]
> > BUG: KMSAN: uninit-value in ax88772_bind+0x93d/0x11e0
> > drivers/net/usb/asix_devices.c:724
> > CPU: 0 PID: 3348 Comm: kworker/0:2 Not tainted 5.1.0+ #1
> > 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+0x191/0x1f0 lib/dump_stack.c:113
> > kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
> > __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
> > is_valid_ether_addr include/linux/etherdevice.h:200 [inline]
> > asix_set_netdev_dev_addr drivers/net/usb/asix_devices.c:73 [inline]
> > ax88772_bind+0x93d/0x11e0 drivers/net/usb/asix_devices.c:724
> > usbnet_probe+0x10f5/0x3940 drivers/net/usb/usbnet.c:1728
> > usb_probe_interface+0xd66/0x1320 drivers/usb/core/driver.c:361
> > really_probe+0xdae/0x1d80 drivers/base/dd.c:513
> > driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
> > __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
> > bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
> > __device_attach+0x454/0x730 drivers/base/dd.c:844
> > device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
> > bus_probe_device+0x137/0x390 drivers/base/bus.c:514
> > device_add+0x288d/0x30e0 drivers/base/core.c:2106
> > usb_set_configuration+0x30dc/0x3750 drivers/usb/core/message.c:2027
> > generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
> > usb_probe_device+0x14c/0x200 drivers/usb/core/driver.c:266
> > really_probe+0xdae/0x1d80 drivers/base/dd.c:513
> > driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
> > __device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
> > bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
> > __device_attach+0x454/0x730 drivers/base/dd.c:844
> > device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
> > bus_probe_device+0x137/0x390 drivers/base/bus.c:514
> > device_add+0x288d/0x30e0 drivers/base/core.c:2106
> > usb_new_device+0x23e5/0x2ff0 drivers/usb/core/hub.c:2534
> > hub_port_connect drivers/usb/core/hub.c:5089 [inline]
> > hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
> > port_event drivers/usb/core/hub.c:5350 [inline]
> > hub_event+0x48d1/0x7290 drivers/usb/core/hub.c:5432
> > process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
> > process_scheduled_works kernel/workqueue.c:2331 [inline]
> > worker_thread+0x189c/0x2460 kernel/workqueue.c:2417
> > kthread+0x4b5/0x4f0 kernel/kthread.c:254
> > ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355
> >
> > Signed-off-by: Phong Tran <[email protected]>
> > ---
> > drivers/net/usb/asix_devices.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/net/usb/asix_devices.c
> > b/drivers/net/usb/asix_devices.c
> > index c9bc96310ed4..f514d19316b1 100644
> > --- a/drivers/net/usb/asix_devices.c
> > +++ b/drivers/net/usb/asix_devices.c
> > @@ -230,6 +230,7 @@ static int ax88172_bind(struct usbnet *dev,
> > struct usb_interface *intf)
> > int i;
> > unsigned long gpio_bits = dev->driver_info->data;
> >
> > + memset(buf, 0, sizeof(buf));
>
> For array variables defined in the function itself, isn't this usually
> done with:
>
> int ret = 0;
> - u8 buf[ETH_ALEN];
> + u8 buf[ETH_ALEN] = {0};
> int i;
> unsigned long gpio_bits = dev->driver_info->data;
>
> eg make the compiler do it (though maybe it's smart enough to elide the
> memset, I don't know). See drivers/net/ethernet/intel/igb/e1000_mac.c
> for an example.
>

Thank suggestion, applied in v2 without using memset().

Phong

2019-07-02 00:11:41

by Phong Tran

[permalink] [raw]
Subject: [PATCH V2] net: usb: asix: init MAC address buffers

This is for fixing bug KMSAN: uninit-value in ax88772_bind

Tested by
https://groups.google.com/d/msg/syzkaller-bugs/aFQurGotng4/eB_HlNhhCwAJ

Reported-by: [email protected]

syzbot found the following crash on:

HEAD commit: f75e4cfe kmsan: use kmsan_handle_urb() in urb.c
git tree: kmsan
console output: https://syzkaller.appspot.com/x/log.txt?x=136d720ea00000
kernel config:
https://syzkaller.appspot.com/x/.config?x=602468164ccdc30a
dashboard link:
https://syzkaller.appspot.com/bug?extid=8a3fc6674bbc3978ed4e
compiler: clang version 9.0.0 (/home/glider/llvm/clang
06d00afa61eef8f7f501ebdb4e8612ea43ec2d78)
syz repro:
https://syzkaller.appspot.com/x/repro.syz?x=12788316a00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=120359aaa00000

==================================================================
BUG: KMSAN: uninit-value in is_valid_ether_addr
include/linux/etherdevice.h:200 [inline]
BUG: KMSAN: uninit-value in asix_set_netdev_dev_addr
drivers/net/usb/asix_devices.c:73 [inline]
BUG: KMSAN: uninit-value in ax88772_bind+0x93d/0x11e0
drivers/net/usb/asix_devices.c:724
CPU: 0 PID: 3348 Comm: kworker/0:2 Not tainted 5.1.0+ #1
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+0x191/0x1f0 lib/dump_stack.c:113
kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622
__msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
is_valid_ether_addr include/linux/etherdevice.h:200 [inline]
asix_set_netdev_dev_addr drivers/net/usb/asix_devices.c:73 [inline]
ax88772_bind+0x93d/0x11e0 drivers/net/usb/asix_devices.c:724
usbnet_probe+0x10f5/0x3940 drivers/net/usb/usbnet.c:1728
usb_probe_interface+0xd66/0x1320 drivers/usb/core/driver.c:361
really_probe+0xdae/0x1d80 drivers/base/dd.c:513
driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x454/0x730 drivers/base/dd.c:844
device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
bus_probe_device+0x137/0x390 drivers/base/bus.c:514
device_add+0x288d/0x30e0 drivers/base/core.c:2106
usb_set_configuration+0x30dc/0x3750 drivers/usb/core/message.c:2027
generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
usb_probe_device+0x14c/0x200 drivers/usb/core/driver.c:266
really_probe+0xdae/0x1d80 drivers/base/dd.c:513
driver_probe_device+0x1b3/0x4f0 drivers/base/dd.c:671
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:778
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x454/0x730 drivers/base/dd.c:844
device_initial_probe+0x4a/0x60 drivers/base/dd.c:891
bus_probe_device+0x137/0x390 drivers/base/bus.c:514
device_add+0x288d/0x30e0 drivers/base/core.c:2106
usb_new_device+0x23e5/0x2ff0 drivers/usb/core/hub.c:2534
hub_port_connect drivers/usb/core/hub.c:5089 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
port_event drivers/usb/core/hub.c:5350 [inline]
hub_event+0x48d1/0x7290 drivers/usb/core/hub.c:5432
process_one_work+0x1572/0x1f00 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x189c/0x2460 kernel/workqueue.c:2417
kthread+0x4b5/0x4f0 kernel/kthread.c:254
ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Signed-off-by: Phong Tran <[email protected]>
---
Changes since v1:
- replace memset() by array init
---
drivers/net/usb/asix_devices.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index c9bc96310ed4..ef548beba684 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -226,7 +226,7 @@ static void asix_phy_reset(struct usbnet *dev, unsigned int reset_bits)
static int ax88172_bind(struct usbnet *dev, struct usb_interface *intf)
{
int ret = 0;
- u8 buf[ETH_ALEN];
+ u8 buf[ETH_ALEN] = {0};
int i;
unsigned long gpio_bits = dev->driver_info->data;

@@ -677,7 +677,7 @@ static int asix_resume(struct usb_interface *intf)
static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf)
{
int ret, i;
- u8 buf[ETH_ALEN], chipcode = 0;
+ u8 buf[ETH_ALEN] = {0}, chipcode = 0;
u32 phyid;
struct asix_common_private *priv;

@@ -1061,7 +1061,7 @@ static const struct net_device_ops ax88178_netdev_ops = {
static int ax88178_bind(struct usbnet *dev, struct usb_interface *intf)
{
int ret;
- u8 buf[ETH_ALEN];
+ u8 buf[ETH_ALEN] = {0};

usbnet_get_endpoints(dev,intf);

--
2.11.0

2019-07-03 00:56:24

by David Miller

[permalink] [raw]
Subject: Re: [PATCH V2] net: usb: asix: init MAC address buffers

From: Phong Tran <[email protected]>
Date: Tue, 2 Jul 2019 07:10:08 +0700

> This is for fixing bug KMSAN: uninit-value in ax88772_bind
>
> Tested by
> https://groups.google.com/d/msg/syzkaller-bugs/aFQurGotng4/eB_HlNhhCwAJ
>
> Reported-by: [email protected]
>
> syzbot found the following crash on:
>
> HEAD commit: f75e4cfe kmsan: use kmsan_handle_urb() in urb.c
> git tree: kmsan
...
> Signed-off-by: Phong Tran <[email protected]>

Applied, thanks.