Am 31.08.21 um 16:20 schrieb Andrew Lunn: > On Tue, Aug 31, 2021 at 06:48:45AM -0700, Jakub Kicinski wrote: >> On Tue, 31 Aug 2021 03:36:23 -0700 syzbot wrote: >>> Hello, >>> >>> syzbot found the following issue on: >>> >>> HEAD commit: 9c1587d99f93 usb: isp1760: otg control register access >>> git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing >>> console output: https://syzkaller.appspot.com/x/log.txt?x=16907291300000 >>> kernel config: https://syzkaller.appspot.com/x/.config?x=24756feea212a6b0 >>> dashboard link: https://syzkaller.appspot.com/bug?extid=6a916267d9bc5fa2d9a6 >>> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 >>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=166de449300000 >>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12c5ddce300000 >>> >>> IMPORTANT: if you fix the issue, please add the following tag to the commit: >>> Reported-by: syzbot+6a916267d9bc5fa2d9a6@xxxxxxxxxxxxxxxxxxxxxxxxx >>> >>> asix 1-1:0.0 eth1: register 'asix' at usb-dummy_hcd.0-1, ASIX AX88178 USB 2.0 Ethernet, 8a:c0:d1:1e:27:4c >>> usb 1-1: USB disconnect, device number 2 >>> asix 1-1:0.0 eth1: unregister 'asix' usb-dummy_hcd.0-1, ASIX AX88178 USB 2.0 Ethernet >>> general protection fault, probably for non-canonical address 0xdffffc00000000c3: 0000 [#1] SMP KASAN >>> KASAN: null-ptr-deref in range [0x0000000000000618-0x000000000000061f] >>> CPU: 1 PID: 32 Comm: kworker/1:1 Not tainted 5.14.0-rc7-syzkaller #0 >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 >>> Workqueue: usb_hub_wq hub_event >>> RIP: 0010:phy_is_started include/linux/phy.h:947 [inline] >>> RIP: 0010:phy_disconnect+0x22/0x110 drivers/net/phy/phy_device.c:1097 >>> Code: 0f 1f 84 00 00 00 00 00 55 48 89 fd 53 e8 46 33 68 fe 48 8d bd 18 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e c5 00 00 00 8b 9d 18 06 00 00 >>> RSP: 0018:ffffc900001a7780 EFLAGS: 00010206 >>> RAX: dffffc0000000000 RBX: ffff88811a410bc0 RCX: 0000000000000000 >>> RDX: 00000000000000c3 RSI: ffffffff82d9305a RDI: 0000000000000618 >>> RBP: 0000000000000000 R08: 0000000000000055 R09: 0000000000000000 >>> R10: ffffffff814c05fb R11: 0000000000000000 R12: ffff8881063cc300 >>> R13: ffffffff83870d90 R14: ffffffff86805a20 R15: ffffffff868059e0 >>> FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 >>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>> CR2: 00007fb4c30b3008 CR3: 00000001021e1000 CR4: 00000000001506e0 >>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >>> Call Trace: >>> ax88772_unbind+0x51/0x90 drivers/net/usb/asix_devices.c:816 > > Looking at the console messages: > > [ 36.456221][ T32] usb 1-1: new high-speed USB device number 2 using dummy_hcd > [ 36.976035][ T32] usb 1-1: New USB device found, idVendor=0df6, idProduct=0056, bcdDevice=42.6c > [ 36.985338][ T32] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 > [ 36.993579][ T32] usb 1-1: Product: syz > [ 36.997817][ T32] usb 1-1: Manufacturer: syz > [ 37.002423][ T32] usb 1-1: SerialNumber: syz > [ 37.013578][ T32] usb 1-1: config 0 descriptor?? > [ 37.276018][ T32] asix 1-1:0.0 (unnamed net_device) (uninitialized): invalid hw address, using random > executing program > [ 37.715517][ T32] asix 1-1:0.0 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 > [ 37.725693][ T32] asix 1-1:0.0 (unnamed net_device) (uninitialized): Failed to send software reset: ffffffb9 > [ 37.925418][ T32] asix 1-1:0.0 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 > [ 37.936461][ T32] asix 1-1:0.0 (unnamed net_device) (uninitialized): Failed to send software reset: ffffffb9 > [ 38.119561][ T32] asix 1-1:0.0 eth1: register 'asix' at usb-dummy_hcd.0-1, ASIX AX88178 USB 2.0 Ethernet, 8a:c0:d1:1e:27:4c > [ 38.138828][ T32] usb 1-1: USB disconnect, device number 2 > [ 38.150689][ T32] asix 1-1:0.0 eth1: unregister 'asix' usb-dummy_hcd.0-1, ASIX AX88178 USB 2.0 Ethernet > > So this is a AX88178, and you would expect it to use > ax88178_bind(). That function never calls ax88772_init_phy() which is > what connects the PHY to the MAC, and sets priv->phydev. > > static void ax88772_unbind(struct usbnet *dev, struct usb_interface *intf) > { > struct asix_common_private *priv = dev->driver_priv; > > phy_disconnect(priv->phydev); > > So this passes a NULL pointer. > > static const struct driver_info ax88178_info = { > .description = "ASIX AX88178 USB 2.0 Ethernet", > .bind = ax88178_bind, > .unbind = ax88772_unbind, > .status = asix_status, > > You cannot pair ax88178_bind with ax88772_unbind. Either a > ax88178_unbind is needed, or ax88772_unbind needs to check for a NULL > pointer. > > Andrew > Yes, this was fixed following patch: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/drivers/net/usb/asix_devices.c?id=1406e8cb4b05fdc67692b1af2da39d7ca5278713 -- Regards, Oleksij
