On Mon, Sep 23, 2019 at 4:31 PM syzbot <syzbot+e8fe6fd37e640743df98@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: e0bd8d79 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=114d95ad600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=8847e5384a16f66a > dashboard link: https://syzkaller.appspot.com/bug?extid=e8fe6fd37e640743df98 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1692f991600000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=145d05b1600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+e8fe6fd37e640743df98@xxxxxxxxxxxxxxxxxxxxxxxxx > > em28xx 1-1:0.240: Audio interface 240 found (Vendor Class) > em28xx 1-1:0.240: unknown em28xx chip ID (0) > em28xx 1-1:0.240: Config register raw data: 0xfffffffb > em28xx 1-1:0.240: AC97 chip type couldn't be determined > em28xx 1-1:0.240: No AC97 audio processor > ================================================================== > BUG: KASAN: use-after-free in __list_add_valid+0xd8/0xf0 lib/list_debug.c:26 > Read of size 8 at addr ffff8881d31d0240 by task kworker/1:1/21 > > CPU: 1 PID: 21 Comm: kworker/1:1 Not tainted 5.3.0+ #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 > __list_add_valid+0xd8/0xf0 lib/list_debug.c:26 > __list_add include/linux/list.h:60 [inline] > list_add_tail include/linux/list.h:93 [inline] > em28xx_init_extension+0x44/0x1f0 > drivers/media/usb/em28xx/em28xx-core.c:1125 > em28xx_init_dev.isra.0+0xa7b/0x15d8 > drivers/media/usb/em28xx/em28xx-cards.c:3520 > em28xx_usb_probe.cold+0xcac/0x2516 > drivers/media/usb/em28xx/em28xx-cards.c:3869 > usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361 > really_probe+0x281/0x6d0 drivers/base/dd.c:548 > driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721 > __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828 > bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430 > __device_attach+0x217/0x360 drivers/base/dd.c:894 > bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490 > device_add+0xae6/0x16f0 drivers/base/core.c:2201 > usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023 > generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210 > usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266 > really_probe+0x281/0x6d0 drivers/base/dd.c:548 > driver_probe_device+0x101/0x1b0 drivers/base/dd.c:721 > __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828 > bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430 > __device_attach+0x217/0x360 drivers/base/dd.c:894 > bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490 > device_add+0xae6/0x16f0 drivers/base/core.c:2201 > usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536 > hub_port_connect drivers/usb/core/hub.c:5098 [inline] > hub_port_connect_change drivers/usb/core/hub.c:5213 [inline] > port_event drivers/usb/core/hub.c:5359 [inline] > hub_event+0x1b5c/0x3640 drivers/usb/core/hub.c:5441 > process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 > process_scheduled_works kernel/workqueue.c:2331 [inline] > worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417 > kthread+0x318/0x420 kernel/kthread.c:255 > ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 > > Allocated by task 238: > save_stack+0x1b/0x80 mm/kasan/common.c:69 > set_track mm/kasan/common.c:77 [inline] > __kasan_kmalloc mm/kasan/common.c:493 [inline] > __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:466 > slab_post_alloc_hook mm/slab.h:520 [inline] > slab_alloc_node mm/slub.c:2770 [inline] > slab_alloc mm/slub.c:2778 [inline] > kmem_cache_alloc+0xd6/0x2d0 mm/slub.c:2783 > shmem_alloc_inode+0x18/0x40 mm/shmem.c:3630 > alloc_inode+0x61/0x1e0 fs/inode.c:227 > new_inode_pseudo+0x14/0xe0 fs/inode.c:916 > new_inode+0x1b/0x40 fs/inode.c:945 > shmem_get_inode+0x84/0x7e0 mm/shmem.c:2228 > shmem_mknod+0x5a/0x1f0 mm/shmem.c:2864 > lookup_open+0x119a/0x18d0 fs/namei.c:3224 > do_last fs/namei.c:3314 [inline] > path_openat+0x1045/0x3f50 fs/namei.c:3525 > do_filp_open+0x1a1/0x280 fs/namei.c:3555 > do_sys_open+0x3c0/0x580 fs/open.c:1089 > do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Freed by task 0: > save_stack+0x1b/0x80 mm/kasan/common.c:69 > set_track mm/kasan/common.c:77 [inline] > __kasan_slab_free+0x130/0x180 mm/kasan/common.c:455 > slab_free_hook mm/slub.c:1423 [inline] > slab_free_freelist_hook mm/slub.c:1474 [inline] > slab_free mm/slub.c:3016 [inline] > kmem_cache_free+0xb9/0x380 mm/slub.c:3032 > i_callback+0x3f/0x70 fs/inode.c:216 > __rcu_reclaim kernel/rcu/rcu.h:222 [inline] > rcu_do_batch kernel/rcu/tree.c:2157 [inline] > rcu_core+0x630/0x1ca0 kernel/rcu/tree.c:2377 > __do_softirq+0x221/0x912 kernel/softirq.c:292 > > The buggy address belongs to the object at ffff8881d31d0000 > which belongs to the cache shmem_inode_cache of size 1184 > The buggy address is located 576 bytes inside of > 1184-byte region [ffff8881d31d0000, ffff8881d31d04a0) > The buggy address belongs to the page: > page:ffffea00074c7400 refcount:1 mapcount:0 mapping:ffff8881da115180 > index:0x0 compound_mapcount: 0 > flags: 0x200000000010200(slab|head) > raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da115180 > raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8881d31d0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8881d31d0180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff8881d31d0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8881d31d0280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8881d31d0300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > > --- > 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 syzkaller@xxxxxxxxxxxxxxxx. > > 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 #syz dup: BUG: corrupted list in em28xx_init_extension
