On Mon, Aug 12, 2019 at 2:18 PM syzbot <syzbot+a4b088ebfbadf5f82150@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: e96407b4 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=1327f2ee600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e > dashboard link: https://syzkaller.appspot.com/bug?extid=a4b088ebfbadf5f82150 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=128acc6a600000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1082c8e2600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+a4b088ebfbadf5f82150@xxxxxxxxxxxxxxxxxxxxxxxxx > > ================================================================== > BUG: KASAN: use-after-free in ld_usb_interrupt_in_callback+0x40c/0x4c0 > drivers/usb/misc/ldusb.c:276 > Write of size 4 at addr ffff8881cdf0b55c by task udevd/238 > > CPU: 1 PID: 238 Comm: udevd Not tainted 5.3.0-rc2+ #25 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > <IRQ> > __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:612 > ld_usb_interrupt_in_callback+0x40c/0x4c0 drivers/usb/misc/ldusb.c:276 #syz dup: KASAN: use-after-free Read in ld_usb_release > __usb_hcd_giveback_urb+0x1f2/0x470 drivers/usb/core/hcd.c:1757 > usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1822 > dummy_timer+0x120f/0x2fa2 drivers/usb/gadget/udc/dummy_hcd.c:1965 > call_timer_fn+0x179/0x650 kernel/time/timer.c:1322 > expire_timers kernel/time/timer.c:1366 [inline] > __run_timers kernel/time/timer.c:1685 [inline] > __run_timers kernel/time/timer.c:1653 [inline] > run_timer_softirq+0x5cc/0x14b0 kernel/time/timer.c:1698 > __do_softirq+0x221/0x912 kernel/softirq.c:292 > invoke_softirq kernel/softirq.c:373 [inline] > irq_exit+0x178/0x1a0 kernel/softirq.c:413 > exiting_irq arch/x86/include/asm/apic.h:537 [inline] > smp_apic_timer_interrupt+0x12f/0x500 arch/x86/kernel/apic/apic.c:1095 > apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828 > </IRQ> > RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] > RIP: 0010:check_kcov_mode kernel/kcov.c:140 [inline] > RIP: 0010:__sanitizer_cov_trace_pc+0x9/0x50 kernel/kcov.c:174 > Code: 25 8c c4 cf 07 41 bc f4 ff ff ff e8 8a a0 ea ff 48 c7 05 76 c4 cf 07 > 00 00 00 00 e9 ee eb ff ff 90 65 48 8b 04 25 00 ef 01 00 <65> 8b 15 e8 ff > c3 7e 81 e2 00 01 1f 00 48 8b 34 24 75 2b 8b 90 20 > RSP: 0018:ffff8881d391fd80 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 > RAX: ffff8881d38b9800 RBX: dffffc0000000000 RCX: ffffffff815ab382 > RDX: 00007fefa32f1000 RSI: 00007fefa32f1000 RDI: 0000000000000006 > RBP: ffff8881d3822b20 R08: ffff8881d38b9800 R09: ffffed103a7f68a7 > R10: ffffed103a7f68a6 R11: ffff8881d3fb4533 R12: 00007fefa32f1000 > R13: 00007fefa32f1000 R14: ffff8881d3822b00 R15: ffff8881d3822b20 > browse_rb mm/mmap.c:346 [inline] > validate_mm+0x2f0/0x610 mm/mmap.c:418 > remove_vma_list mm/mmap.c:2592 [inline] > __do_munmap+0x847/0xf90 mm/mmap.c:2833 > __vm_munmap+0xe6/0x170 mm/mmap.c:2853 > __do_sys_munmap mm/mmap.c:2878 [inline] > __se_sys_munmap mm/mmap.c:2875 [inline] > __x64_sys_munmap+0x62/0x80 mm/mmap.c:2875 > do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x7fefa33ccd37 > Code: f0 ff ff 73 01 c3 48 8b 0d fe c0 2a 00 31 d2 48 29 c2 64 89 11 48 83 > c8 ff eb ea 90 90 90 90 90 90 90 90 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff > ff 73 01 c3 48 8b 0d d1 c0 2a 00 31 d2 48 29 c2 64 > RSP: 002b:00007ffc17b3cfe8 EFLAGS: 00000206 ORIG_RAX: 000000000000000b > RAX: ffffffffffffffda RBX: 0000000000ffdd10 RCX: 00007fefa33ccd37 > RDX: 0000000000000000 RSI: 0000000000001000 RDI: 00007fefa3cc2000 > RBP: 0000000000000000 R08: 00007fefa3cbc7a0 R09: 0000000000000000 > R10: 5f4344555f425355 R11: 0000000000000206 R12: 0000000000000000 > R13: 0000000000ffdd10 R14: 0000000000000006 R15: 0000000000000000 > > Allocated by task 1757: > save_stack+0x1b/0x80 mm/kasan/common.c:69 > set_track mm/kasan/common.c:77 [inline] > __kasan_kmalloc mm/kasan/common.c:487 [inline] > __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:460 > kmalloc include/linux/slab.h:552 [inline] > kzalloc include/linux/slab.h:748 [inline] > ld_usb_probe+0x6e/0xa65 drivers/usb/misc/ldusb.c:661 > usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361 > really_probe+0x281/0x650 drivers/base/dd.c:548 > driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709 > __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816 > bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:882 > bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x16f0 drivers/base/core.c:2114 > 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+0x281/0x650 drivers/base/dd.c:548 > driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709 > __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816 > bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:882 > bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x16f0 drivers/base/core.c:2114 > 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 > worker_thread+0x96/0xe20 kernel/workqueue.c:2415 > kthread+0x318/0x420 kernel/kthread.c:255 > ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 > > Freed by task 1757: > 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:449 > slab_free_hook mm/slub.c:1423 [inline] > slab_free_freelist_hook mm/slub.c:1470 [inline] > slab_free mm/slub.c:3012 [inline] > kfree+0xe4/0x2f0 mm/slub.c:3953 > ld_usb_probe+0x728/0xa65 drivers/usb/misc/ldusb.c:744 > usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361 > really_probe+0x281/0x650 drivers/base/dd.c:548 > driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709 > __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816 > bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:882 > bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x16f0 drivers/base/core.c:2114 > 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+0x281/0x650 drivers/base/dd.c:548 > driver_probe_device+0x101/0x1b0 drivers/base/dd.c:709 > __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:816 > bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454 > __device_attach+0x217/0x360 drivers/base/dd.c:882 > bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514 > device_add+0xae6/0x16f0 drivers/base/core.c:2114 > 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 > worker_thread+0x96/0xe20 kernel/workqueue.c:2415 > kthread+0x318/0x420 kernel/kthread.c:255 > ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 > > The buggy address belongs to the object at ffff8881cdf0b400 > which belongs to the cache kmalloc-512 of size 512 > The buggy address is located 348 bytes inside of > 512-byte region [ffff8881cdf0b400, ffff8881cdf0b600) > The buggy address belongs to the page: > page:ffffea000737c280 refcount:1 mapcount:0 mapping:ffff8881da002500 > index:0x0 compound_mapcount: 0 > flags: 0x200000000010200(slab|head) > raw: 0200000000010200 ffffea00072c5400 0000000200000002 ffff8881da002500 > raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8881cdf0b400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8881cdf0b480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff8881cdf0b500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8881cdf0b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8881cdf0b600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ================================================================== > > > --- > 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