Hello Dan, On Mon, Jul 1, 2019 at 10:30 PM Dan Williams <dcbw@xxxxxxxxxx> 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: syzbot+8a3fc6674bbc3978ed4e@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > 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 <tranmanphong@xxxxxxxxx> > > --- > > 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
