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;

Affected: Ubuntu:Pro:14.04:LTS: libdbi-perl, Ubuntu:Pro:16.04:LTS: libdbi-perl, Ubuntu:Pro:18.04:LTS: libdbi-perl, Ubuntu:Pro:20.04:LTS: libdbi-perl, Ubuntu:22.04:LTS: libdbi-perl, Ubuntu:24.04:LTS: libdbi-perl, Ubuntu:26.04:LTS: libdbi-perl

[Fix FetchHashKeyName on IV/NV]