UBSAN: undefined-behaviour in erofs_fill_super

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 015e94d0 Linux 4.19.146
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=158dc8d3900000
kernel config: https://syzkaller.appspot.com/x/.config?x=243dd74ad58a8a57
dashboard link: https://syzkaller.appspot.com/bug?extid=fb7f8baf6114ca56065e
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fb7f8b...@syzkaller.appspotmail.com

erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: read_super, device -> /dev/loop2
erofs: options ->
================================================================================
UBSAN: Undefined behaviour in drivers/staging/erofs/super.c:122:3
shift exponent 55 is too large for 32-bit type 'int'
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
CPU: 1 PID: 20271 Comm: syz-executor.4 Not tainted 4.19.146-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+0x22c/0x33e lib/dump_stack.c:118
ubsan_epilogue+0xe/0x3a lib/ubsan.c:161
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
__ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 lib/ubsan.c:422
superblock_read drivers/staging/erofs/super.c:122 [inline]
erofs_read_super drivers/staging/erofs/super.c:356 [inline]
erofs_fill_super+0x397/0x12fc drivers/staging/erofs/super.c:499
mount_bdev+0x2fc/0x3b0 fs/super.c:1158
erofs_mount+0x8c/0xc0 drivers/staging/erofs/super.c:512
mount_fs+0xa3/0x318 fs/super.c:1261
vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
vfs_kern_mount fs/namespace.c:951 [inline]
do_new_mount fs/namespace.c:2469 [inline]
do_mount+0x51c/0x2f10 fs/namespace.c:2799
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
ksys_mount+0xcf/0x130 fs/namespace.c:3015
__do_sys_mount fs/namespace.c:3029 [inline]
__se_sys_mount fs/namespace.c:3026 [inline]
__x64_sys_mount+0xba/0x150 fs/namespace.c:3026
do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x46004a
Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da 89 fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007f2524af7a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
erofs: blksize 1 isn't supported on this platform
RAX: ffffffffffffffda RBX: 00007f2524af7b20 RCX: 000000000046004a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f2524af7ae0
RBP: 00007f2524af7ae0 R08: 00007f2524af7b20 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020000040
================================================================================
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: blksize 8388608 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: blksize 1073741824 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop4
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: blksize 1073741824 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: read_super, device -> /dev/loop2
erofs: root inode @ nid 0
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop4
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop3
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop3
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop3
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
netlink: 28 bytes leftover after parsing attributes in process `syz-executor.5'.
netlink: 'syz-executor.5': attribute type 51 has an invalid length.
erofs: read_super, device -> /dev/loop3
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: options ->
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: read_super, device -> /dev/loop2
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop2
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: options ->
erofs: read_super, device -> /dev/loop4
erofs: blksize 1 isn't supported on this platform
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop3
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop2
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop4
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop3
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: read_super, device -> /dev/loop3
erofs: blksize 1 isn't supported on this platform
erofs: options ->
erofs: root inode @ nid 0
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: read_super, device -> /dev/loop2
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: options ->
erofs: blksize 1 isn't supported on this platform
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'.
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop3
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
erofs: options ->
erofs: root inode @ nid 0
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop2
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: blksize 1 isn't supported on this platform
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop4
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: options ->
erofs: read_super, device -> /dev/loop2
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: options ->
erofs: root inode @ nid 0
erofs: blksize 1 isn't supported on this platform
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: read_super, device -> /dev/loop4
erofs: read_super, device -> /dev/loop3
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
erofs: read_super, device -> /dev/loop4
erofs: options ->
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
(unnamed net_device) (uninitialized): option lp_interval: invalid value (0)
(unnamed net_device) (uninitialized): option lp_interval: allowed values 1 - 2147483647
netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop3
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: options ->
erofs: root inode @ nid 0
erofs: root inode @ nid 0
erofs: read_super, device -> /dev/loop2
erofs: options ->
erofs: blksize 1 isn't supported on this platform
netlink: 8 bytes leftover after parsing attributes in process `syz-executor.5'.
erofs: read_super, device -> /dev/loop4
erofs: options ->
erofs: root inode @ nid 0


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 015e94d0 Linux 4.19.146
git tree: linux-4.19.y

console output: https://syzkaller.appspot.com/x/log.txt?x=13eab84b900000

kernel config: https://syzkaller.appspot.com/x/.config?x=243dd74ad58a8a57
dashboard link: https://syzkaller.appspot.com/bug?extid=fb7f8baf6114ca56065e
compiler: gcc (GCC) 10.1.0-syz 20200507

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15661fb5900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12988ec5900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fb7f8b...@syzkaller.appspotmail.com

audit: type=1400 audit(1600622589.906:8): avc: denied { execmem } for pid=6493 comm="syz-executor855" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
erofs: read_super, device -> /dev/loop0

erofs: options ->
================================================================================
UBSAN: Undefined behaviour in drivers/staging/erofs/super.c:122:3
shift exponent 55 is too large for 32-bit type 'int'

CPU: 0 PID: 6493 Comm: syz-executor855 Not tainted 4.19.146-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+0x22c/0x33e lib/dump_stack.c:118
ubsan_epilogue+0xe/0x3a lib/ubsan.c:161

__ubsan_handle_shift_out_of_bounds.cold+0x1c4/0x250 lib/ubsan.c:422
superblock_read drivers/staging/erofs/super.c:122 [inline]
erofs_read_super drivers/staging/erofs/super.c:356 [inline]
erofs_fill_super+0x397/0x12fc drivers/staging/erofs/super.c:499
mount_bdev+0x2fc/0x3b0 fs/super.c:1158
erofs_mount+0x8c/0xc0 drivers/staging/erofs/super.c:512
mount_fs+0xa3/0x318 fs/super.c:1261
vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
vfs_kern_mount fs/namespace.c:951 [inline]
do_new_mount fs/namespace.c:2469 [inline]
do_mount+0x51c/0x2f10 fs/namespace.c:2799

ksys_mount+0xcf/0x130 fs/namespace.c:3015
__do_sys_mount fs/namespace.c:3029 [inline]
__se_sys_mount fs/namespace.c:3026 [inline]
__x64_sys_mount+0xba/0x150 fs/namespace.c:3026
do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293

entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446d4a
Code: b8 08 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 fd ad fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 da ad fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007ffe5db93678 EFLAGS: 00000297 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffe5db936d0 RCX: 0000000000446d4a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007ffe5db93690
RBP: 00007ffe5db93690 R08: 00007ffe5db936d0 R09: 00007ffe00000015
R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000002
R13: 0000000000000004 R14: 0000000000000003 R15: 00000000