[PATCH 0/2] smb: client: fix "df: Resource temporarily unavailable" on 5.10 stable kernel

[kovalev]

After mounting a remote cifs resource, it becomes unavailable:
df: /mnt/sambashare: Resource temporarily unavailable

It was tested on the following Linux kernels:
Linux altlinux 5.10.208-std-def-alt1
Linux fedora 5.10.208-200.el8.x86_64

The error appeared starting from kernel 5.10.206 after adding
the commit [1] "smb: client: fix OOB in SMB2_query_info_init()",
in which the buffer length increases by 1 as a result of changes:
..
-      iov[0].iov_len = total_len - 1 + input_len;
+      iov[0].iov_len = len;
..

[1] https://patchwork.kernel.org/project/cifs-client/patch/20231213152557.6634-2-pc@xxxxxxxxxxxxx/

Error fixed by backported commits in next two patches  adapted for the 5.10 kernel:

[PATCH 1/2] stddef: Introduce DECLARE_FLEX_ARRAY() helper
[PATCH 2/2] smb3: Replace smb2pdu 1-element arrays with flex-arrays