On Thu, Aug 13, 2020 at 04:29:07PM +0100, John Garry wrote: > Hi, > > I see this on today's linux-next with notably KASAN and > DEBUG_TEST_DRIVER_REMOVE enabled: > > [58.045441] hub 6-0:1.0: 1 port detected > [58.050894] xhci_hcd 0000:7a:02.0: remove, state 1 > [58.055698] usb usb6: USB disconnect, device number 1 > [58.063151] xhci_hcd 0000:7a:02.0: USB bus 6 deregistered > [58.068598] xhci_hcd 0000:7a:02.0: remove, state 1 > [58.073396] usb usb5: USB disconnect, device number 1 > [58.082040] xhci_hcd 0000:7a:02.0: USB bus 5 deregistered > [58.088446] > ================================================================== > [58.095667] BUG: KASAN: use-after-free in usb_hcd_pci_remove+0xbc/0x168 > [58.102272] Read of size 8 at addr ffff002a0b6e8120 by task swapper/0/1 > [58.108875] > [58.110361] CPU: 2 PID: 1 Comm: swapper/0 Tainted: G > W5.8.0-next-20200813-dirty #31 > [58.119396] Hardware name: Huawei D06 /D06, BIOS Hisilicon D06 UEFI RC0 - > V1.16.01 03/15/2019 > [58.127910] Call trace: > [58.130351] dump_backtrace+0x0/0x2d0 > [58.134005] show_stack+0x18/0x28 > [58.137313] dump_stack+0xf4/0x168 > [58.140709] print_address_description.constprop.12+0x6c/0x4ec > [58.146532] kasan_report+0x130/0x200 > [58.150186] __asan_load8+0x9c/0xd8 > [58.153666] usb_hcd_pci_remove+0xbc/0x168 > [58.157755] xhci_pci_remove+0xb8/0x108 > [58.161583] pci_device_remove+0x6c/0x138 > [58.165586] really_probe+0x22c/0x640 > [58.169240] driver_probe_device+0x78/0xe8 > [58.173328] device_driver_attach+0x9c/0xa8 > [58.177504] __driver_attach+0x74/0x120 > [58.181331] bus_for_each_dev+0xec/0x160 > [58.185245] driver_attach+0x34/0x48 > [58.188812] bus_add_driver+0x1b8/0x2c0 > [58.192639] driver_register+0xc0/0x1e0 > [58.196467] __pci_register_driver+0xb4/0xd0 > [58.200729] xhci_pci_init+0x60/0x70 > [58.204297] do_one_initcall+0xd4/0x264 > [58.208125] kernel_init_freeable+0x270/0x2d8 > [58.212475] kernel_init+0x14/0x124 > [58.215955] ret_from_fork+0x10/0x34 > [58.216996] hub 1-1:1.0: USB hub found > [58.219519] > [58.219523] Allocated by task 13: > [58.219528] kasan_save_stack+0x28/0x58 > [58.219538] __kasan_kmalloc.isra.6+0xcc/0xf0 > [58.236219] kasan_kmalloc+0x10/0x20 > [58.239786] __kmalloc+0x194/0x290 > [58.243181] __usb_create_hcd+0x48/0x3a8 > [58.247095] usb_create_hcd+0x1c/0x28 > [58.250748] usb_hcd_pci_probe+0xa0/0x548 > [58.254749] xhci_pci_probe+0x54/0x360 > [58.258488] local_pci_probe+0x78/0xf8 > [58.262230] work_for_cpu_fn+0x30/0x50 > [58.265971] process_one_work+0x424/0x698 > [58.269972] worker_thread+0x438/0x6d0 > [58.273713] kthread+0x224/0x230 > [58.276933] ret_from_fork+0x10/0x34 > [58.280497] > [58.281978] Freed by task 1: > [58.284851] kasan_save_stack+0x28/0x58 > [58.288677] kasan_set_track+0x28/0x40 > [58.292418] kasan_set_free_info+0x24/0x48 > [58.296505] __kasan_slab_free+0x104/0x188 > [58.300593] kasan_slab_free+0x14/0x20 > [58.304333] slab_free_freelist_hook+0x8c/0x190 > [58.308855] kfree+0x2cc/0x400 > [58.311901] usb_put_hcd+0xc0/0x110 > [58.315381] usb_hcd_pci_remove+0xb4/0x168 > [58.317397] hub 1-1:1.0: 4 ports detected > [58.319468] xhci_pci_remove+0xb8/0x108 > [58.319473] pci_device_remove+0x6c/0x138 > [58.319480] really_probe+0x22c/0x640 > [58.334943] driver_probe_device+0x78/0xe8 > [58.339031] device_driver_attach+0x9c/0xa8 > [58.343205] __driver_attach+0x74/0x120 > [58.347033] bus_for_each_dev+0xec/0x160 > [58.350947] driver_attach+0x34/0x48 > [58.354513] bus_add_driver+0x1b8/0x2c0 > [58.358340] driver_register+0xc0/0x1e0 > [58.362168] __pci_register_driver+0xb4/0xd0 > [58.366429] xhci_pci_init+0x60/0x70 > [58.369995] do_one_initcall+0xd4/0x264 > [58.373823] kernel_init_freeable+0x270/0x2d8 > [58.378171] kernel_init+0x14/0x124 > [58.381651] ret_from_fork+0x10/0x34 > [58.385215] > [58.386699] The buggy address belongs to the object at ffff002a0b6e8000 > [58.386699] which belongs to the cache kmalloc-8k of size 8192 > [58.399207] The buggy address is located 288 bytes inside of > [58.399207] 8192-byte region [ffff002a0b6e8000, ffff002a0b6ea000) > [58.411019] The buggy address belongs to the page: > [58.415803] page:0000000060c9fcec refcount:1 mapcount:0 > mapping:0000000000000000 index:0x0 pfn:0x2a0b6e8 > [58.425272] head:0000000060c9fcec order:3 compound_mapcount:0 > compound_pincount:0 > [58.432746] flags: 0x2ffff00000010200(slab|head) > [58.437357] raw: 2ffff00000010200 dead000000000100 dead000000000122 > ffff002a53c0f300 > [58.445092] raw: 0000000000000000 0000000080020002 00000001ffffffff > 0000000000000000 > [58.452824] page dumped because: kasan: bad access detected > [58.458385] > [58.459867] Memory state around the buggy address: > [58.464649] ffff002a0b6e8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb > fb > [58.471862] ffff002a0b6e8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > fb > [58.479074] >ffff002a0b6e8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > fb > [58.486284] ^ > [58.490545] ffff002a0b6e8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > fb > [58.497758] ffff002a0b6e8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > fb > [58.504968] > ================================================================== > [58.512179] Disabling lock debugging due to kernel taint > [58.519143] xhci_hcd 0000:7a:02.0: xHCI Host Controller > [58.524428] xhci_hcd 0000:7a:02.0: new USB bus registered, assigned bus > number 5 > [58.532155] xhci_hcd 0000:7a:02.0: hcc params 0x0220f66d hci version 0x100 > quirks 0x0000000000000010 > [58.545434] hub 5-0:1.0: USB hub found > [58.549366] hub 5-0:1.0: 1 port detected > [58.554496] hub 5-0:1.0: USB hub found > [58.558406] hub 5-0:1.0: 1 port detected > [58.565161] hub 5-0:1.0: USB hub found > [58.569080] hub 5-0:1.0: 1 port detected > [58.574234] hub 5-0:1.0: USB hub found > [58.578419] hub 5-0:1.0: 1 port detected > [58.583849] xhci_hcd 0000:7a:02.0: xHCI Host Controller > [58.589112] xhci_hcd 0000:7a:02.0: new USB bus registered, assigned bus > number 6 > [58.596755] xhci_hcd 0000:7a:02.0: Host supports USB 3.0 SuperSpeed > [58.603283] usb usb6: We don't know the algorithms for LPM for this host, > disabling LPM. > [58.614147] hub 6-0:1.0: USB hub found > [58.618068] hub 6-0:1.0: 1 port detected > [58.623291] hub 6-0:1.0: USB hub found > [58.627197] hub 6-0:1.0: 1 port detected > [58.633993] hub 6-0:1.0: USB hub found > [58.638412] hub 6-0:1.0: 1 port detected > [58.643593] hub 6-0:1.0: USB hub found > [58.647537] hub 6-0:1.0: 1 port detected > [58.654020] xhci_hcd 0000:ba:02.0: xHCI Host Controller > [58.659323] xhci_hcd 0000:ba:02.0: new USB bus registered, assigned bus > number 7 > [58.667086] xhci_hcd 0000:ba:02.0: hcc params 0x0220f66d hci version 0x100 > quirks 0x0000000000000010 > [58.680638] hub 7-0:1.0: USB hub found > [58.684572] hub 7-0:1.0: 1 port detected > [58.689782] hub 7-0:1.0: USB hub found > [58.693700] hub 7-0:1.0: 1 port detected > [58.709559] hub 7-0:1.0: USB hub found > [58.713571] hub 7-0:1.0: 1 port detected > [58.718955] xhci_hcd 0000:ba:02.0: xHCI Host Controller > [58.724567] xhci_hcd 0000:ba:02.0: new USB bus registered, assigned bus > number 8 > [58.731996] xhci_hcd 0000:ba:02.0: Hos.0: remove, state 1 > [58.793746] usb usb8: USB disconnect, device number 1 > [58.801364] xhci_hcd 0000:ba:02.0: USB bus 8 deregistered > [58.806815] xhci_hcd 0000:ba:02.0: remove, state 1 > [58.811614] usb usb7: USB disconnect, device number 1 > [58.820394] xhci_hcd 0000:ba:02.0: USB bus 7 deregistered > [58.826505] xhci_hcd 0000:ba:02.0: xHCI Host Controller > [58.831811] xhci_hcd 0000:ba:02.0: new USB bus registered, assigned bus > number 7 > [58.839569] xhci_hcd 0000:ba:02.0: hcc params 0x0220f66d hci version 0x100 > quirks 0x0000000000000010 > [58.852983] hub 7-0:1.0: USB hub found > [58.856908] hub 7-0:1.0: 1 port detected > [58.862044] hub 7-0:1.0: USB hub found > [58.865959] hub 7-0:1.0: 1 port detected > [58.872577] hub 7-0:1.0: USB hub found > [58.876491] hub 7-0:1.0: 1 port detected > [58.881760] hub 7-0:1.0: USB hub found > [58.885678] hub 7-0:1.0: 1 port detected > [58.891037] xhci_hcd 0000:ba:02.0: xHCI Host Controller > [58.896550] xhci_hcd 0000:ba:02.0: new USB bus registered, assigned bus > number 8 > [58.903968] xhci_hcd 0000:ba:02.0: Host supports USB 3.0 SuperSpeed > [58.910471] usb usb8: We don't know the algorithms for LPM for this host, > disabling LPM. > [58.921427] hub 8-0:1.0: USB hub found > [58.925533] hub 8-0:1.0: 1 port detected > [58.930781] hub 8-0:1.0: USB hub found > [58.934695] hub 8-0:1.0: 1 port detected > [58.941649] hub 8-0:1.0: USB hub found > [58.945728] hub 8-0:1.0: 1 port detected > [58.950967] hub 8-0:1.0: USB hub found > [58.954894] hub 8-0:1.0: 1 port detected > [58.961651] usbcore: registered new interface driver usb-storage > > Ring any bells? I don't mind debugging the real issue, but good to know it's > not already solved. I didn't see anything on linux-usb archives, apart from > this: > https://lore.kernel.org/linux-usb/1566554761464.60146@xxxxxxxxxx/ which > doesn't look too familiar. > > I couldn't recreate on v5.8, but this triggering this seems a bit fragile > even on linux-next. Looks new. Any chance you can run 'git bisect' to track this down? thanks, greg k-h
