[yocto] bash getcwd errors when running under OverlayFS

[Craig McQueen]

I am using an OverlayFS patch for kernel 3.14.x obtained from OpenWRT. Once I started using OverlayFS, I found that bash shell scripts would give a lot of errors, something like:

     shell-init: error retrieving current directory: getcwd: cannot access parent directories: Success
     job-working-directory: error retrieving current directory: getcwd: cannot access parent directories: No such file or directory
     chdir: error retrieving current directory: getcwd: cannot access parent directories: Bad file descriptor

It seems that this can be traced to an internal implementation of getcwd() in bash. When cross-compiled, it can't check for getcwd() use of malloc, so it is cautious and sets GETCWD_BROKEN and uses an internal implementation of getcwd(). This internal implementation doesn't seem to work well with OverlayFS.

A simple fix in Yocto is to put the following in a recipes-extended/bash/bash_4.3.bbappend in your own layer:

    EXTRA_OECONF += "bash_cv_getcwd_malloc=yes"

-- 
Craig McQueen