syzbot has found a reproducer for the following issue on: HEAD commit: 1d94330a Merge tag 'for-5.11/dm-fixes-1' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13210c3b500000 kernel config: https://syzkaller.appspot.com/x/.config?x=c60c9ff9cc916cbc dashboard link: https://syzkaller.appspot.com/bug?extid=a32b546d58dde07875a1 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17d14c58d00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15a2feb8d00000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a32b546d58dde07875a1@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ WARNING: CPU: 1 PID: 8613 at fs/io_uring.c:9096 io_uring_flush+0x326/0x3a0 fs/io_uring.c:9096 Modules linked in: CPU: 1 PID: 8613 Comm: syz-executor948 Not tainted 5.11.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:io_uring_flush+0x326/0x3a0 fs/io_uring.c:9096 Code: e9 58 fe ff ff e8 aa e3 9a ff 49 c7 84 24 a0 00 00 00 00 00 00 00 e9 aa fe ff ff e8 74 9e dd ff e9 91 fd ff ff e8 8a e3 9a ff <0f> 0b e9 51 ff ff ff e8 6e 9e dd ff e9 06 fd ff ff 4c 89 f7 e8 61 RSP: 0018:ffffc90001a4faa0 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88801113b780 RSI: ffffffff81d7e636 RDI: 0000000000000003 RBP: ffff88801c862280 R08: 0000000000000000 R09: 00000000196e5401 R10: ffffffff81d7e585 R11: 0000000000000000 R12: ffff888019724000 R13: ffff8880196e5401 R14: ffff888019724040 R15: ffff8880197240d0 FS: 0000000000000000(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000025f8e000 CR4: 0000000000350ef0 Call Trace: filp_close+0xb4/0x170 fs/open.c:1280 close_files fs/file.c:401 [inline] put_files_struct fs/file.c:416 [inline] put_files_struct+0x1cc/0x350 fs/file.c:413 exit_files+0x7e/0xa0 fs/file.c:433 do_exit+0xc22/0x2ae0 kernel/exit.c:820 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x3e9/0x20a0 kernel/signal.c:2770 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x446b69 Code: Unable to access opcode bytes at RIP 0x446b3f. RSP: 002b:00007fbb80bcecf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00000000006dbc28 RCX: 0000000000446b69 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28 RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c R13: 00007ffc1b88469f R14: 00007fbb80bcf9c0 R15: 00000000006dbc2c