kernel BUG at drivers/dma-buf/dma-buf.c:LINE!

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 63623fd4 Merge tag 'for-linus' of git://git.kernel.org/pub..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=177bf331e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9833e26bab355358
dashboard link: https://syzkaller.appspot.com/bug?extid=d6734079f30f7fc39021
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=109d3ac3e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+d67340...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at drivers/dma-buf/dma-buf.c:99!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 18500 Comm: syz-executor.0 Not tainted 5.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:dma_buf_release+0x35b/0x420 drivers/dma-buf/dma-buf.c:99
Code: 00 00 e8 f8 d3 ec fc 4c 89 e7 45 31 e4 e8 ed 7a 35 fd e8 38 25 f7 fc 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 25 25 f7 fc <0f> 0b e8 1e 25 f7 fc 4c 89 ef e8 46 eb 00 00 eb 97 e8 0f 25 f7 fc
RSP: 0018:ffffc9000296fdc8 EFLAGS: 00010293
RAX: ffff888094086300 RBX: 0000000000000004 RCX: ffffffff847e6fc5
RDX: 0000000000000000 RSI: ffffffff847e722b RDI: 0000000000000005
RBP: ffffc9000296fdf0 R08: ffff888094086300 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808c6ec800
R13: ffff88808e6ecd7c R14: ffff88808e6ecd28 R15: ffff888097011940
FS: 0000000002b7b940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000008a9e80 CR3: 00000000916f0000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164
prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x416011
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:00007fff23e39030 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 0000000000416011
RDX: 0000000000000000 RSI: 0000000000000081 RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000000 R09: 01ffffffffffffff
R10: 0000000000770938 R11: 0000000000000293 R12: 000000000076bf20
R13: 0000000000770948 R14: 0000000000000000 R15: 000000000076bf2c
Modules linked in:
---[ end trace 432bc1955550b75d ]---
RIP: 0010:dma_buf_release+0x35b/0x420 drivers/dma-buf/dma-buf.c:99
Code: 00 00 e8 f8 d3 ec fc 4c 89 e7 45 31 e4 e8 ed 7a 35 fd e8 38 25 f7 fc 44 89 e0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 25 25 f7 fc <0f> 0b e8 1e 25 f7 fc 4c 89 ef e8 46 eb 00 00 eb 97 e8 0f 25 f7 fc
RSP: 0018:ffffc9000296fdc8 EFLAGS: 00010293
RAX: ffff888094086300 RBX: 0000000000000004 RCX: ffffffff847e6fc5
RDX: 0000000000000000 RSI: ffffffff847e722b RDI: 0000000000000005
RBP: ffffc9000296fdf0 R08: ffff888094086300 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808c6ec800
R13: ffff88808e6ecd7c R14: ffff88808e6ecd28 R15: ffff888097011940
FS: 0000000002b7b940(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000008a9e80 CR3: 00000000916f0000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
This bug is generated by a bot. It may contain errors.
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[syzbot]

syzbot suspects this issue was fixed by commit:

commit e722a295cf493388dae474745d30e91e1a2ec549
Author: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Date: Thu Aug 27 12:36:27 2020 +0000

staging: ion: remove from the tree

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17d4f137500000
start commit: abb3438d Merge tag 'm68knommu-for-v5.9-rc3' of git://git.k..
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=978db74cb30aa994
dashboard link: https://syzkaller.appspot.com/bug?extid=d6734079f30f7fc39021
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17428596900000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: staging: ion: remove from the tree

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Dmitry Vyukov]

The reproducer opens /dev/ion