Created attachment 298630 [details] [review]
Make sure not to block

The following commit introduced a regression:

https://github.com/GNOME/gnome-keyring/commit/2ca51a0aef5b1bc41f2e71d2b65edc8478dab69d#diff-d53c4eabb39a8d87b804f97577ee83cdR395

In the case where (res != GKD_CONTROL_RESULT_OK), calls to sigaction (SIGPIPE, &ignpipe, &oldpipe); and sigaction (SIGCHLD, &defchld, &oldchld); are not followed by sigaction (SIGCHLD, &oldchld, NULL); and sigaction (SIGPIPE, &oldpipe, NULL);

https://github.com/GNOME/gnome-keyring/blob/master/pam/gkr-pam-client.c#L421

Blocking SIGCHLD is problematic in particular for the MDM display manager which slave relies on that signal to acknowledge the death of its greeter.. thus resulting in an inability to log in.

I attached a patch which fixes this issue by adding the missing calls to the if() statement. Otherwise, on IRC Stef mentioned it might be nice to use a goto in order to factorize code for common return paths, that might be better even.