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Subjectpossible deadlock in mon_bin_vma_fault
From
Hello,

syzbot found the following crash on:

HEAD commit: 58c3f14f86c9 Merge tag 'riscv-for-linus-4.19-rc2' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12fc6f0e400000
kernel config: https://syzkaller.appspot.com/x/.config?x=531a917630d2a492
dashboard link: https://syzkaller.appspot.com/bug?extid=56f9673bb4cdcbeb0e92
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13dca13e400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17cbe492400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+56f9673bb4cdcbeb0e92@syzkaller.appspotmail.com

vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0

======================================================
WARNING: possible circular locking dependency detected
4.19.0-rc1+ #215 Not tainted
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
------------------------------------------------------
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
syz-executor605/4648 is trying to acquire lock:
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
00000000a9171a30 (&rp->fetch_lock){+.+.}, at: mon_bin_vma_fault+0xdc/0x4a0
drivers/usb/mon/mon_bin.c:1237

but task is already holding lock:
0000000069e9aac4 (&mm->mmap_sem){++++}, at: __mm_populate+0x31a/0x4d0
mm/gup.c:1250
vhci_hcd: default hub control req: 0000 v0000 i0000 l0

which lock already depends on the new lock.

vhci_hcd: default hub control req: 0000 v0000 i0000 l0

the existing dependency chain (in reverse order) is:
vhci_hcd: default hub control req: 0000 v0000 i0000 l0

-> #1 (&mm->mmap_sem){++++}:
__might_fault+0x155/0x1e0 mm/memory.c:4578
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
_copy_to_user+0x30/0x110 lib/usercopy.c:25
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
copy_to_user include/linux/uaccess.h:155 [inline]
mon_bin_read+0x334/0x650 drivers/usb/mon/mon_bin.c:825
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__vfs_read+0x117/0x9b0 fs/read_write.c:416
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vfs_read+0x17f/0x3c0 fs/read_write.c:452
ksys_read+0x101/0x260 fs/read_write.c:578
__do_sys_read fs/read_write.c:588 [inline]
__se_sys_read fs/read_write.c:586 [inline]
__x64_sys_read+0x73/0xb0 fs/read_write.c:586
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
vhci_hcd: default hub control req: 0000 v0000 i0000 l0

-> #0 (&rp->fetch_lock){+.+.}:
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
lock_acquire+0x1e4/0x4f0 kernel/locking/lockdep.c:3901
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0x171/0x1700 kernel/locking/mutex.c:1073
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
mon_bin_vma_fault+0xdc/0x4a0 drivers/usb/mon/mon_bin.c:1237
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__do_fault+0xee/0x450 mm/memory.c:3240
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
do_read_fault mm/memory.c:3652 [inline]
do_fault mm/memory.c:3752 [inline]
handle_pte_fault mm/memory.c:3983 [inline]
__handle_mm_fault+0x2b4a/0x4350 mm/memory.c:4107
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
handle_mm_fault+0x53e/0xc80 mm/memory.c:4144
faultin_page mm/gup.c:518 [inline]
__get_user_pages+0x823/0x1b50 mm/gup.c:718
populate_vma_page_range+0x2db/0x3d0 mm/gup.c:1222
__mm_populate+0x286/0x4d0 mm/gup.c:1270
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
mm_populate include/linux/mm.h:2307 [inline]
vm_mmap_pgoff+0x27f/0x2c0 mm/util.c:362
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
ksys_mmap_pgoff+0x4da/0x660 mm/mmap.c:1585
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline]
__x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

vhci_hcd: default hub control req: 0000 v0000 i0000 l0
Possible unsafe locking scenario:

vhci_hcd: default hub control req: 0000 v0000 i0000 l0
CPU0 CPU1
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
---- ----
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
lock(&mm->mmap_sem);
lock(&rp->fetch_lock);
lock(&mm->mmap_sem);
lock(&rp->fetch_lock);
vhci_hcd: default hub control req: 0000 v0000 i0000 l0

*** DEADLOCK ***

vhci_hcd: default hub control req: 0000 v0000 i0000 l0
1 lock held by syz-executor605/4648:
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
#0: 0000000069e9aac4 (&mm->mmap_sem){++++}, at: __mm_populate+0x31a/0x4d0
mm/gup.c:1250
vhci_hcd: default hub control req: 0000 v0000 i0000 l0

stack backtrace:
CPU: 1 PID: 4648 Comm: syz-executor605 Not tainted 4.19.0-rc1+ #215
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
Call Trace:
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
print_circular_bug.isra.34.cold.55+0x1bd/0x27d
kernel/locking/lockdep.c:1222
check_prev_add kernel/locking/lockdep.c:1862 [inline]
check_prevs_add kernel/locking/lockdep.c:1975 [inline]
validate_chain kernel/locking/lockdep.c:2416 [inline]
__lock_acquire+0x3449/0x5020 kernel/locking/lockdep.c:3412
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
lock_acquire+0x1e4/0x4f0 kernel/locking/lockdep.c:3901
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0x171/0x1700 kernel/locking/mutex.c:1073
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
mon_bin_vma_fault+0xdc/0x4a0 drivers/usb/mon/mon_bin.c:1237
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__do_fault+0xee/0x450 mm/memory.c:3240
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
do_read_fault mm/memory.c:3652 [inline]
do_fault mm/memory.c:3752 [inline]
handle_pte_fault mm/memory.c:3983 [inline]
__handle_mm_fault+0x2b4a/0x4350 mm/memory.c:4107
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
handle_mm_fault+0x53e/0xc80 mm/memory.c:4144
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
faultin_page mm/gup.c:518 [inline]
__get_user_pages+0x823/0x1b50 mm/gup.c:718
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
populate_vma_page_range+0x2db/0x3d0 mm/gup.c:1222
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__mm_populate+0x286/0x4d0 mm/gup.c:1270
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
mm_populate include/linux/mm.h:2307 [inline]
vm_mmap_pgoff+0x27f/0x2c0 mm/util.c:362
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
ksys_mmap_pgoff+0x4da/0x660 mm/mmap.c:1585
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline]
__x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
RIP: 0033:0x444c09
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 2b ce fb ff c3 66 2e 0f 1f 84 00 00 00 00
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
RSP: 002b:00007ffc31ed6738 EFLAGS: 00000216 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444c09
RDX: 0000000001fffffd RSI: 0000000000400000 RDI: 0000000020a05000
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
R10: 0000000000008011 R11: 0000000000000216 R12: 0000000000401ec0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
R13: 0000000000401f50 R14: 0000000000000000 R15: 0000000000000000
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0
vhci_hcd: default hub control req: 0000 v0000 i0000 l0


---
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@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with
syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

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