KASAN: use-after-free Read in usb_free_coherent

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    7f7867ff 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=13efa030600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=792eb47789f57810
dashboard link: https://syzkaller.appspot.com/bug?extid=d1fedb1c1fdb07fca507
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+d1fedb1c1fdb07fca507@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: use-after-free in usb_free_coherent+0x79/0x80  
drivers/usb/core/usb.c:928
Read of size 8 at addr ffff8881b18599c8 by task syz-executor.4/16007

CPU: 0 PID: 16007 Comm: syz-executor.4 Not tainted 5.3.0-rc2+ #23
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
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:612
 usb_free_coherent+0x79/0x80 drivers/usb/core/usb.c:928
 yurex_delete+0x138/0x330 drivers/usb/misc/yurex.c:100
 kref_put include/linux/kref.h:65 [inline]
 yurex_release+0x66/0x90 drivers/usb/misc/yurex.c:392
 __fput+0x2d7/0x840 fs/file_table.c:280
 task_work_run+0x13f/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x1d2/0x200 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x45f/0x580 arch/x86/entry/common.c:299
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x413511
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48  
83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48  
89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007ffc424ea2e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000413511
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 0000000000000001 R08: 0000000029a2fc22 R09: 0000000029a2fc26
R10: 00007ffc424ea3c0 R11: 0000000000000293 R12: 000000000075c9a0
R13: 000000000075c9a0 R14: 0000000000761938 R15: ffffffffffffffff

Allocated by task 2776:
 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]
 usb_alloc_dev+0x51/0xf95 drivers/usb/core/usb.c:583
 hub_port_connect drivers/usb/core/hub.c:5004 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
 port_event drivers/usb/core/hub.c:5359 [inline]
 hub_event+0x15c0/0x3640 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 16007:
 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
 device_release+0x71/0x200 drivers/base/core.c:1064
 kobject_cleanup lib/kobject.c:693 [inline]
 kobject_release lib/kobject.c:722 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x171/0x280 lib/kobject.c:739
 put_device+0x1b/0x30 drivers/base/core.c:2213
 usb_put_dev+0x1f/0x30 drivers/usb/core/usb.c:725
 yurex_delete+0x40/0x330 drivers/usb/misc/yurex.c:95
 kref_put include/linux/kref.h:65 [inline]
 yurex_release+0x66/0x90 drivers/usb/misc/yurex.c:392
 __fput+0x2d7/0x840 fs/file_table.c:280
 task_work_run+0x13f/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x1d2/0x200 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x45f/0x580 arch/x86/entry/common.c:299
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881b1859980
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 72 bytes inside of
 2048-byte region [ffff8881b1859980, ffff8881b185a180)
The buggy address belongs to the page:
page:ffffea0006c61600 refcount:1 mapcount:0 mapping:ffff8881da00c000  
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 0000000000000000 0000000100000001 ffff8881da00c000
raw: 0000000000000000 00000000000f000f 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881b1859880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881b1859900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881b1859980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff8881b1859a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881b1859a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


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