PAMCONVERR

PAMCONVERR is the informal name used to denote the PAM_CONV_ERR error code in the Pluggable Authentication Module (PAM) API. This error code signals a failure in the conversation function used to exchange prompts and responses between a PAM module and the application. The PAM API defines a pam_conv structure and a set of return values for the conversation callback; PAM_CONV_ERR is raised when the conversation function cannot process a request or supply a response.

In practice, PAM_CONV_ERR can arise from problems in the pam_conv implementation, such as invalid message arrays, null pointers, memory allocation failures, or an application that terminates the dialog unexpectedly. It can also result from misconfiguration of the PAM stack or from a module that returns an error during message handling.

When PAM_CONV_ERR is observed, authentication may fail or the user may be blocked from proceeding, depending on the configured control flags and the stack order. Debugging usually involves enabling PAM debugging, reviewing system logs, and inspecting the pam_conv function code and any involved pam_message and pam_response structures. Ensuring proper memory management, input validation, and compatibility between the module and application helps prevent this error.

See also PAM, pam_conv, PAM_CONV_ERR.