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 -512 sending data on socket to server
------------[ cut here ]------------
server->in_flight == 0
WARNING: fs/smb/client/smb2ops.c:104 at smb2_add_credits+0x1213/0x1790 fs/smb/client/smb2ops.c:104, CPU#0: syz.1.48/5976
Modules linked in:
CPU: 0 UID: 0 PID: 5976 Comm: syz.1.48 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:smb2_add_credits+0x1213/0x1790 fs/smb/client/smb2ops.c:104
Code: c6 e8 d1 69 b0 fe 84 db 0f 85 0a fb ff ff e8 b4 6f b0 fe 48 8d 3d ad ea f0 0d 67 48 0f b9 3a e9 f4 fa ff ff e8 9e 6f b0 fe 90 <0f> 0b 90 0f b6 05 58 63 d1 0d 31 ff 89 c6 88 44 24 28 e8 96 69 b0
RSP: 0018:ffffc900032a7208 EFLAGS: 00010287
RAX: 0000000000005fcc RBX: ffff88803142a300 RCX: ffffc9000473a000
RDX: 0000000000080000 RSI: ffffffff835bb012 RDI: ffff88802ff9a580
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc900032a7448
R13: 0000000000000200 R14: 0000000000000001 R15: ffff88803142a000
FS:  00007f3ee506b6c0(0000) GS:ffff888123b56000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32d01ff8 CR3: 0000000074bdd000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 add_credits fs/smb/client/cifsglob.h:894 [inline]
 compound_send_recv+0x1030/0x2a10 fs/smb/client/transport.c:978
 cifs_send_recv+0x43/0x60 fs/smb/client/transport.c:1105
 SMB2_negotiate+0x15c4/0x5380 fs/smb/client/smb2pdu.c:1189
 cifs_negotiate_protocol fs/smb/client/connect.c:4049 [inline]
 cifs_negotiate_protocol+0x268/0x4c0 fs/smb/client/connect.c:4020
 cifs_get_smb_ses+0xfc9/0x2170 fs/smb/client/connect.c:2501
 cifs_mount_get_session+0xf8/0x460 fs/smb/client/connect.c:3587
 get_session fs/smb/client/dfs.c:65 [inline]
 dfs_mount_share+0x200/0x1e20 fs/smb/client/dfs.c:275
 cifs_mount+0xc4/0xdb0 fs/smb/client/connect.c:3869
 cifs_smb3_do_mount+0x2c0/0x1b10 fs/smb/client/cifsfs.c:1026
 smb3_get_tree_common fs/smb/client/fs_context.c:897 [inline]
 smb3_get_tree fs/smb/client/fs_context.c:917 [inline]
 smb3_get_tree+0x1fd/0x440 fs/smb/client/fs_context.c:909
 vfs_get_tree+0x92/0x320 fs/super.c:1933
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3772 [inline]
 do_new_mount fs/namespace.c:3848 [inline]
 path_mount+0x7d0/0x24c0 fs/namespace.c:4168
 do_mount fs/namespace.c:4181 [inline]
 __do_sys_mount fs/namespace.c:4397 [inline]
 __se_sys_mount fs/namespace.c:4374 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4374
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3ee419e159
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:00007f3ee506b028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3ee4425fa0 RCX: 00007f3ee419e159
RDX: 0000200000000200 RSI: 0000200000000100 RDI: 0000200000000500
RBP: 00007f3ee423506b R08: 0000200000000300 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3ee4426038 R14: 00007f3ee4425fa0 R15: 00007fff68addc38
 </TASK>