std::fs::copy failed with OS error 1 on Linux when copying over CIFS from local FS

[vadixidav]

I am using the following versions:

• mount.cifs version: 6.9
• uname -r: 5.3.0-23-generic
• Ubuntu 19.10
• Rust nightly-2019-11-17-x86_64-unknown-linux-gnu

I was unable to perform a file copy with std::fs::copy when copying to a Windows shared folder mounted on Linux with the following options:

rw,nounix,iocharset=utf8,file_mode=0777,dir_mode=0777

I got OS error 1, which shouldn't happen since everyone has full permissions to the mounted NAS.

Interestingly, I was able to copy the files using cp -r without issue. I worked around this by writing something close to the following (all same except for error handling that I stripped out):

        for file in WalkDir::new(&source)
            .into_iter()
            .map(|file| file.unwrap())
            .filter(|file| file.file_type().is_file())
        {
            let outpath = dest_dir_name.join(file.file_name());
            std::io::copy(&mut File::open(&file.path()), &mut File::create(&outpath).unwrap()).unwrap();
        }

It seemed strange to me that I get a permission denied despite that if I manually write the code to create and write the files using walkdir then it works completely file. I believe this is a bug in the code of std::fs::copy since the expected behavior is that it should work like cp (which just copies it as expected).

I still have access to this setup, so I can test things if need be. Let me know if I can give more information to track down the bug.

[the8472]

can you strace the failure?