Created attachment 1564994 [details]
patch file

Description of problem:
After upgrading to pam_ssh 2.x, private key files stored on filesystems which do not permit root access (e.g NFS with root squash) are no longer loaded. When the pam_ssh debug (log) option is enabled for the pam session module interface, the error "inexistent configuration directory" is logged.

Version-Release number of selected component (if applicable):
2.0 and newer


How reproducible:
Always.


Steps to Reproduce:
1. Configure filesystem with root squash or some mechanism which prevents root access
2. Create SSH key file(s) on filesystem
3. Configure pam stack to use pam_ssh module
4. Log into the system

Actual results:
ssh-agent is spawned, the key is decrypted but not loaded into ssh-agent.

Expected results:
ssh-agent is spawned, the key is both decrypted and loaded into ssh-agent.

Additional info:
The change to handle inexistent configuration directories was made in version 2.0 and is mentioned explicitly in the package changelog.
Because pam_ssh attempts to access the .ssh directory as root, filesystems which prevent root access (e.g. NFS with root squash enabled) prevent this behaviour and cause the error.

The attached patch resolves this issue by modifying the relevant error condition so that a directory is only "inexistent" if both the directory could not be accessed and the error returned is NOT EACCES (access denied). The patch also improves logging by reporting the absolute path of the .ssh directory that could not be accessed, and the error string.