I don't quite understand the problem but I can recommend this solution (especially if I allow for some cut'n'paste errors): 

my $user = $query->param('user');
my $password = $query->param('password');
my @buffer;    # !!! Added this line.
{
  no strict;
  $filename = $query->param('foofile');
  undef $/;
  my $buffer = <$filename>;   # !!! Added "my" here.
  $buffer =~ tr/\r\n/\n/;
  @buffer= split /\n/, $buffer;
}
print $buffer[0];

[download]
Without a change like that, the print $buffer[0]; line should have generated a fatal error.

Update: amelinda was kind enough to /msg me that this has already been tried. That seems very odd so I'll resort to voodoo programming (if I were working on this myself I'd instead be debugging to check what 0+\@buffer and 0+\@main::buffer evaluate to both inside and outside that block to try to figure out what bizarre thing was going on): 

my $user = $query->param('user');
my $password = $query->param('password');
my @buffer= do {
  local( $/ ); #= undef
  no strict;
  my $filename = $query->param('foofile');
  split /\r?\n/, <$filename>;
}
print $buffer[0];

[download]

        - tye (but my friends call me "Tye")

In reply to (tye)Re2: CGI Upload with OLD CGI.pm by tye
in thread CGI Upload with OLD CGI.pm by amelinda

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