Hello, syzbot found the following crash on: HEAD commit: e2cf67f6 Merge tag 'zonefs-5.6-rc7' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1217e987e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=90791b5aec4dc636 dashboard link: https://syzkaller.appspot.com/bug?extid=b636fe4123f39f69c35b compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16773d8de00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1309b523e00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+b636fe4123f39f69c35b@xxxxxxxxxxxxxxxxxxxxxxxxx Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: mpol_to_str+0x3ec/0x3f0 mm/mempolicy.c:2962 CPU: 1 PID: 1 Comm: systemd Not tainted 5.6.0-rc7-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+0x1e9/0x30e lib/dump_stack.c:118 panic+0x264/0x7a0 kernel/panic.c:221 __stack_chk_fail+0x1c/0x20 kernel/panic.c:667 mpol_to_str+0x3ec/0x3f0 mm/mempolicy.c:2962 shmem_show_mpol mm/shmem.c:1406 [inline] shmem_show_options+0x3d9/0x4c0 mm/shmem.c:3609 show_mountinfo+0x68d/0x790 fs/proc_namespace.c:187 seq_read+0x9df/0xd20 fs/seq_file.c:268 __vfs_read+0xa7/0x6f0 fs/read_write.c:425 vfs_read+0x1c0/0x3f0 fs/read_write.c:461 ksys_read+0x115/0x220 fs/read_write.c:587 do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f83e3f3f92d Code: 2d 2c 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 de 9b 01 00 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 27 9c 01 00 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffe6d4b18c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055840db5f6d0 RCX: 00007f83e3f3f92d RDX: 0000000000000400 RSI: 000055840db5f900 RDI: 000000000000002b RBP: 0000000000000d68 R08: 00007f83e5975500 R09: 00000000000000e0 R10: 000055840db5fce2 R11: 0000000000000293 R12: 00007f83e41fa440 R13: 00007f83e41f9900 R14: 000000000000001e R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. --- 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches
