syzbot

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WARNING: CPU: 0 PID: 6843 at fs/overlayfs/file.c:81 ovl_change_flags fs/overlayfs/file.c:81 [inline]
WARNING: CPU: 0 PID: 6843 at fs/overlayfs/file.c:81 ovl_real_fdget_meta+0x49c/0x530 fs/overlayfs/file.c:132
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 6843 Comm: syz-executor401 Not tainted 5.9.0-rc1-next-20200818-syzkaller #0
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+0x18f/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:231
 __warn.cold+0x20/0x4a kernel/panic.c:600
 report_bug+0x1bd/0x210 lib/bug.c:198
 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:ovl_change_flags fs/overlayfs/file.c:81 [inline]
RIP: 0010:ovl_real_fdget_meta+0x49c/0x530 fs/overlayfs/file.c:132
Code: ff 4c 89 ff e8 95 da 29 ff e9 ff fc ff ff e8 8b da 29 ff e9 c5 fc ff ff 4c 89 f7 e8 ee da 29 ff e9 5d fd ff ff e8 b4 be e9 fe <0f> 0b 41 bd fb ff ff ff e9 fd fc ff ff e8 72 da 29 ff e9 84 fb ff
RSP: 0018:ffffc900051ffa78 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000002000 RCX: ffffffff828a9579
RDX: ffff88809f2ac3c0 RSI: ffffffff828a97ac RDI: 0000000000000005
RBP: 0000000004048000 R08: 0000000000000000 R09: ffff88809f2acca8
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880989b4a80
R13: ffff8880854cd478 R14: 000000000000a000 R15: ffff8880989b4b00
 ovl_real_fdget fs/overlayfs/file.c:139 [inline]
 ovl_splice_read+0x83/0x1f0 fs/overlayfs/file.c:396
 do_splice_to+0x10b/0x170 fs/splice.c:870
 splice_direct_to_actor+0x307/0x980 fs/splice.c:950
 do_splice_direct+0x1b3/0x280 fs/splice.c:1059
 do_sendfile+0x55f/0xd40 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1601 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4403d9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe42b8c948 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004403d9
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 000000000000bd96 R11: 0000000000000246 R12: 0000000000401be0
R13: 0000000000401c70 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..