CIFS: No dialect specified on mount. Default has changed to a more secure dialect, SMB2.1 or later (e.g. SMB3.1.1), from CIFS (SMB1). To use the less secure SMB1 dialect to access old servers which do not support SMB3.1.1 (or even SMB3 or SMB2.1) specify vers=1.0 on mount.
CIFS: Attempting to mount //127.0.0.1/share
CIFS: VFS: \\127.0.0.1 Error -32 sending data on socket to server
------------[ cut here ]------------
server->in_flight == 0
WARNING: fs/smb/client/smb2ops.c:104 at smb2_add_credits+0x1249/0x2b70 fs/smb/client/smb2ops.c:104, CPU#1: syz.1.151/6444
Modules linked in:
CPU: 1 UID: 0 PID: 6444 Comm: syz.1.151 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:smb2_add_credits+0x1249/0x2b70 fs/smb/client/smb2ops.c:104
Code: de 83 e6 01 31 ff e8 36 c6 b8 fe f6 c3 01 75 0a e8 2c c1 b8 fe e9 22 13 00 00 0f 1f 44 00 00 e8 1d c1 b8 fe e9 13 13 00 00 90 <0f> 0b 90 80 3d 68 c9 54 0d 01 0f 85 9e 03 00 00 e8 02 c1 b8 fe 49
RSP: 0018:ffffc9000381f238 EFLAGS: 00010246
RAX: ffffffff830f0c98 RBX: 1ffff1100f106461 RCX: ffff888034abbe80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000200 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff830f39f0 R12: ffff888078832308
R13: ffffc9000381f450 R14: ffff888078832000 R15: 0000000000000000
FS:  00007fcb178656c0(0000) GS:ffff888124dca000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1c3235da08 CR3: 0000000031aa9000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 add_credits fs/smb/client/cifsglob.h:894 [inline]
 compound_send_recv+0x13b4/0x2b90 fs/smb/client/transport.c:978
 cifs_send_recv+0x42/0x60 fs/smb/client/transport.c:1105
 SMB2_negotiate+0x164d/0x4030 fs/smb/client/smb2pdu.c:1189
 cifs_negotiate_protocol+0x286/0x680 fs/smb/client/connect.c:4049
 cifs_get_smb_ses+0x1104/0x1ff0 fs/smb/client/connect.c:2501
 cifs_mount_get_session+0xf1/0x450 fs/smb/client/connect.c:3587
 get_session fs/smb/client/dfs.c:65 [inline]
 dfs_mount_share+0x22e/0x990 fs/smb/client/dfs.c:275
 cifs_mount+0xcc/0xbf0 fs/smb/client/connect.c:3869
 cifs_smb3_do_mount+0x2d0/0x8a0 fs/smb/client/cifsfs.c:1026
 smb3_get_tree_common fs/smb/client/fs_context.c:897 [inline]
 smb3_get_tree+0x2dd/0x400 fs/smb/client/fs_context.c:917
 vfs_get_tree+0x92/0x2a0 fs/super.c:1933
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3772 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3848
 do_mount fs/namespace.c:4181 [inline]
 __do_sys_mount fs/namespace.c:4397 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4374
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcb1699e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcb17865028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fcb16c26090 RCX: 00007fcb1699e159
RDX: 0000200000000400 RSI: 0000200000000300 RDI: 0000200000000200
RBP: 00007fcb16a3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcb16c26128 R14: 00007fcb16c26090 R15: 00007ffec6da6708
 </TASK>