Hello,
on my mail server running postfix + amavisd, amavisd was dying occasionally when
using File::LibMagic to analyze mail messages.
I can reproduce it on the server (OpenBSD the-server 5.9 GENERIC.MP#3 amd64)
with this Perl script:
> #!/usr/bin/perl
>
> use File::LibMagic;
>
> my $file = shift;
> $file || die "usage: $0 <file>\n";
>
> my $magic = File::LibMagic->new();
>
> for(my $i = 0; $i < 100000; $i++) {
> my $desc = $magic->describe_filename($file);
> if ($i % 100 == 0) { print "."; }
> }
using the following file (see bottom for b64 encoded version):
# cat -tv p005
> $OpenBSD$
>
> Use C codegen for mlton-20130715.
> See https://github.com/MLton/mlton/issues/148 for details.
>
> --- mlyacc/Makefile.orig^IThu May 26 13:14:56 2016
> +++ mlyacc/Makefile^IThu May 26 13:15:10 2016
> @@ -13,7 +13,7 @@ BIN := $(BUILD)/bin
> LIB := $(BUILD)/lib
> MLTON := mlton
> TARGET := self
> -FLAGS := -target $(TARGET)
> +FLAGS := -codegen c -target $(TARGET)
> NAME := mlyacc
> PATH := $(BIN):$(shell echo $$PATH)
>
Sometimes it core dumps on the very first iteration, sometimes it takes 100.
I've fixed the problem on my server by configuring amavisd to use /usr/bin/file
instead, which is not a problem because the server does not handle a high
volume.
Maybe someone who is more skilled debugging perl core dumps than I would like to
have a crack at fixing the problem?
cheers,
Rob Urban
-- snip --
base-64 encoded version of "p005":
> begin-base64 644 p005.gz
> H4sICEQHXVcCA3AwMDUAbZDLbsJADEXX9Vd4kQUonQzDs4pUiaRQGimBqoQPSIKTjDokiBkW/H3z
> aFUVdWPJ9rm+tq3dmSp/v7IADprwBbP6SAVVmNcXPClTV2w8EpPRQswc2BNhacxZu5wX0pTX1Mnq
> E4/CBuMdzKXWV9JcTJ+6CUcyiVTaAWCMNfNuSZbxKPmkXCpy6ossHuLyilFyw/EcxcQVU3c2x8Zy
> DrZt3yvu4ZkrRj28XCITk8cF2l1sUj/YovuM1sA/BOFqyFNZAYaB/6eoZAoYhfGuY7sTAGPvY7OO
> 24ImlQN7Db3Nvk2ZSS4FmUbeI0Owf3s/j8v+wXDrReveob0H8N2L374XCbZD1xrokpRCysoaLavt
> NiL4At4kOzWdAQAA
> ====
