Erro "Não é possível gravar no diretório da fila" e outros problemas do sendmail após atualizar o linode do Debian 8 para o Stable

Question

eu seguieste tutorialpara atualizar minha instância linode do Debian 8 para Stable. Após essa atualização, tive vários erros/problemas com o sendmail.

1. $ which sendmailnão retorna nada. EUfazertenha o sendmail instalado. Está em /usr/sbin/sendmail.

2. As permissões do Sendmail são as seguintes:

   $ ls -la /usr/sbin/sendmail lrwxrwxrwx 1 root root 26 Jul 17 12:41 /usr/sbin/sendmail -> /etc/alternatives/sendmail

   O link ( /etc/alternatives/sendmail) está destacado em vermelho.

3. Quando tento enviar um e-mail de teste, recebo o seguinte erro:sudo echo "Subject: sendmail test" | /usr/sbin/sendmail -v [email protected]

   can not write to queue directory /var/spool/mqueue-client/ (RunAsGid=115, required=0): Permission denied

   Queas permissões do diretório são:

   $ ls -la /var/spool/mqueue-client drwxrwxr-x 2 root root 4096 Sep 15 2018 mqueue-client

Então, obviamente, tenho algum tipo de problema de permissão/propriedade, mas também acho que há algo mais acontecendo com os itens 1 e 2. Preciso poder receber e-mails do OSSEC e do Fail2ban do sistema, então não posso realmente ir sem um cliente/servidor de e-mail funcionando. Só não tenho certeza de como corrigir esses problemas.

Meu sendmail foi simplesmente instalado com $ sudo apt-get install sendmail sendmail-bin, então veio direto dos repositórios do Debian, e é por isso que estou um pouco confuso com esses problemas... Presumi que qualquer configuração necessária seria tratada pelo processo de instalação.

EDITAR: a saída dels -l /etc/alternatives/sendmail*

lrwxrwxrwx 1 root root 24 Jul 17 12:41 /etc/alternatives/sendmail -> /usr/lib/sm.bin/sendmail
lrwxrwxrwx 1 root root 42 Jul 17 12:41 /etc/alternatives/sendmail.8.gz -> /usr/share/man/man8/sendmail.sendmail.8.gz

lrwxrwxrwx 1 root root 24 Jul 17 12:41 /etc/alternatives/sendmail-msp -> /usr/lib/sm.bin/sendmail
lrwxrwxrwx 1 root root 42 Jul 17 12:41 /etc/alternatives/sendmail-msp.8.gz -> /usr/share/man/man8/sendmail.sendmail.8.gz

lrwxrwxrwx 1 root root 24 Jul 17 12:41 /etc/alternatives/sendmail-mta -> /usr/lib/sm.bin/sendmail
lrwxrwxrwx 1 root root 42 Jul 17 12:41 /etc/alternatives/sendmail-mta.8.gz -> /usr/share/man/man8/sendmail.sendmail.8.gz

Cada par termina em uma cor diferente, por exemplo, /usr/lib/sm.bin/sendmailé destacado em âmbar, enquanto /usr/share/man/man8/sendmail.sendmail.8.gzé destacado em vermelho. São as mesmas cores – âmbar e vermelho – para cada par.

EDIT2: A saída de (echo subject: test; echo ; echo test) | /usr/sbin/sendmail -d44.4 -i -v username(usei meu nome de usuário real, mas ajustei a saída resultante por segurança):

$ (echo subject: test; echo ; echo test) | /usr/sbin/sendmail -d44.4 -i -v username
safefile(/etc/mail/submit.cf, uid=1000, gid=0, flags=6000, mode=400):
safedirpath(/etc/mail, uid=1000, gid=0, flags=6000, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 4]   OK
safefile(/etc/mail/relay-domains, uid=1000, gid=0, flags=6580, mode=400):
safedirpath(/etc/mail, uid=1000, gid=0, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    No such file or directory
safefile(/etc/mail/service.switch, uid=1000, gid=115, flags=6480, mode=400):
safedirpath(/etc/mail, uid=1000, gid=115, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 4]   OK
safefile(/etc/mail/service.switch, uid=1000, gid=115, flags=6480, mode=400):
safedirpath(/etc/mail, uid=1000, gid=115, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 4]   OK
safefile( , uid=1000, gid=115, flags=40, mode=660):
safedirpath(., uid=1000, gid=115, flags=40, level=0, offset=0):
    [dir .] OK
    No such file or directory
    [final dir . uid 111 mode 42770] Success
safedirpath(/var/spool/mqueue-client, uid=1000, gid=115, flags=0, level=0, offset=0):
    [dir /var/spool/mqueue-client] OK
safefile(./dfx6MIGnM5005502, uid=1000, gid=115, flags=2040, mode=600):
safedirpath(., uid=1000, gid=115, flags=2040, level=0, offset=0):
    [dir .] OK
    No such file or directory
    [final dir . uid 111 mode 42770] Success
username... Connecting to [127.0.0.1] via relay...
220 major-productions.com ESMTP Sendmail 8.15.2/8.15.2/Debian-12; Mon, 22 Jul 2019 14:16:49 -0400; (No UCE/UBE) logging access from: localhost(OK)-localhost [127.0.0.1]
>>> EHLO major-productions.com
250-major-productions.com Hello localhost [127.0.0.1], pleased to meet you
250-ENHANCEDSTATUSCODES
250-PIPELINING
250-EXPN
250-VERB
250-8BITMIME
250-SIZE
250-DSN
250-ETRN
250-AUTH DIGEST-MD5 CRAM-MD5
250-DELIVERBY
250 HELP
>>> VERB
250 2.0.0 Verbose mode
>>> MAIL From:<[email protected]> SIZE=20 [email protected]
250 2.1.0 <[email protected]>... Sender ok
>>> RCPT To:<[email protected]>
>>> DATA
250 2.1.5 <[email protected]>... Recipient ok
354 Enter mail, end with "." on a line by itself
>>> .
421 4.3.0 collect: Cannot write ./dfx6MIGnHm005503 (bfcommit, uid=0, gid=115): No such file or directory
>>> QUIT
username... Deferred: 421 4.3.0 collect: Cannot write ./dfx6MIGnHm005503 (bfcommit, uid=0, gid=115): No such file or directory
safefile(/var/lib/sendmail/sm-client.st, uid=1000, gid=115, flags=2282, mode=600):
safedirpath(/var/lib/sendmail, uid=1000, gid=115, flags=2282, level=0, offset=0):
    [dir /var/lib/sendmail] OK
    No such file or directory
safefile(/var/lib/sendmail/sm-client.st, uid=1000, gid=115, flags=2282, mode=600):
safedirpath(/var/lib/sendmail, uid=1000, gid=115, flags=2282, level=0, offset=0):
    [dir /var/lib/sendmail] OK
    No such file or directory
Closing connection to [127.0.0.1]

EDIT 3: a saída de (echo subject: test; echo ; echo test) | /usr/sbin/sendmail -Am -d44.4 -i -v usernameenquanto estiver logado como root (com o nome de usuário ofuscado como antes):

# (echo subject: test; echo ; echo test) | /usr/sbin/sendmail -Am -d44.4 -i -v username
safefile(/etc/mail/sendmail.cf, uid=0, gid=0, flags=6000, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=6000, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 400]     OK
safefile(/etc/mail/local-host-names, uid=0, gid=0, flags=6580, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 400]     OK
safefile(/etc/mail/relay-domains, uid=0, gid=0, flags=6580, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    No such file or directory
safefile(/etc/mail/service.switch, uid=0, gid=0, flags=6480, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 400]     OK
safefile(/etc/mail/service.switch, uid=0, gid=0, flags=6480, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 400]     OK
safedirpath(/var/spool/mqueue, uid=0, gid=0, flags=4, level=0, offset=0):
    [dir /var/spool/mqueue] OK
safefile(/etc/mail/service.switch, uid=0, gid=0, flags=6480, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=6580, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 0, nlink 1, stat 100644, mode 400]     OK
safefile(/etc/mail/aliases.db, uid=0, gid=0, flags=584, mode=400):
safedirpath(/etc/mail, uid=0, gid=0, flags=584, level=0, offset=0):
    [dir /etc/mail] OK
    [uid 110, nlink 1, stat 100640, mode 400]   OK
safedirpath(/home/username, uid=1000, gid=1000, flags=1985, level=0, offset=0):
    [dir /home/username] OK
safefile(/home/username/.forward.major-productions, uid=1000, gid=1000, flags=1895, mode=400):
    No such file or directory
safedirpath(/home/username, uid=1000, gid=1000, flags=1985, level=0, offset=0):
    [dir /home/username] OK
safefile(/home/username/.forward, uid=1000, gid=1000, flags=1895, mode=400):
    No such file or directory
safefile(./dfx6MKLN6r006080, uid=0, gid=0, flags=2040, mode=600):
safedirpath(., uid=0, gid=0, flags=2040, level=0, offset=0):
    [dir .] OK
    No such file or directory
    [final dir . uid 0 mode 40700] Success
username... Connecting to local...
safefile(/usr/sbin/sensible-mda, uid=0, gid=0, flags=41904, mode=0):
safedirpath(/usr/sbin, uid=0, gid=0, flags=41904, level=0, offset=0):
    [dir /usr/sbin] OK
    [uid 0, nlink 1, stat 104755, mode 0]   OK
username... Sent
safefile(/var/lib/sendmail/sendmail.st, uid=0, gid=0, flags=2282, mode=600):
safedirpath(/var/lib/sendmail, uid=0, gid=0, flags=2282, level=0, offset=0):
    [dir /var/lib/sendmail] OK
    No such file or directory
safefile(/var/lib/sendmail/sendmail.st, uid=0, gid=0, flags=2282, mode=600):
safedirpath(/var/lib/sendmail, uid=0, gid=0, flags=2282, level=0, offset=0):
    [dir /var/lib/sendmail] OK
    No such file or directory

Answer 1

1. $ which sendmailnão retorna nada.

sendmail NÃO Éinstalado em usuários não privilegiados PATH=> você observa o resultado esperado/normal. sendmailespera-se que seja executado por outros programas mailque usam caminho completo/absoluto.

3. não é possível gravar no diretório da fila /var/spool/mqueue-client/ (RunAsGid=115, obrigatório=0): Permissão negada

corrigir /var/spool/mqueue-clientpermissões e propriedade

chown smmsp:smmsp /var/spool/mqueue-client`   
chmod 02770 /var/spool/mqueue-client`

O SENDMAIL MODERNO NÃO REQUER SER CONFIGURADO COMO INSTALADO COMOSET ROOT ID

veja os resultados ls -l --dereference /usr/sbin/sendmailnos comentários da pergunta:
-r-sr-sr-t 1 root smmsp 860672 Sep 15 2018 /usr/sbin/sendmail

Altere a permissão do destino final /usr/sbin/sendmaile /etc/alternativesdos links no Debian:

chmod u-s /usr/lib/sm.bin/sendmail

Answer 2

Funciona se você executar isto:

echo "Subject: sendmail test" | sudo sendmail /usr/sbin/sendmail -v [email protected]

A diferença é que você está executando o echo como root, mas não o sendmail.

Assim a mensagem: "(RunAsGid=115, required=0): Permissão negada"

O "115" é o ID do grupo do seu usuário e espera "0" (que é root)