DBI versions before 1.654 for Perl incorrectly treat numeric values as strings in FetchHashKeyName.

fetchrow hashref uses the string pointer of the FetchHashKeyName attribute as the key name without stringifying it first. When FetchHashKeyName has been set to an integer (IV) or floating-point (NV) value, that pointer is invalid, so reading the key name triggers a segmentation fault.

This can be triggered with the following code:

my $dbh = DBI->connect( "dbi:ExampleP:", "", "", { RaiseError => 0, PrintError => 0 } ); $dbh->{FetchHashKeyName} = 42;

my $sth = $dbh->prepare("select mode, size, name from ."); $sth->execute; $sth->fetchrow hashref;