Re: [Bug Report] 2.4.3 on macOS: anvil panics at anvil-connection.c:727 on every IMAP client handshake

> On 18/04/2026 05:15 EEST I-K-D-T--- via dovecot <[email protected]> wrote:
> 
>  
> Hi Dovecot developers,
>    I'm hitting a reproducible anvil panic on macOS when any IMAP client tries
>    to connect. Every client handshake triggers an `i_unreached()` assertion
>    in
>    `anvil-connection.c:727`, causing the anvil child to be killed with
>    SIGABRT.
>    Dovecot keeps restarting anvil, but every subsequent connection attempt
>    triggers the same panic, so the service effectively cannot accept logins.
>    ## Environment
>    - Dovecot: 2.4.3 (e278b1e09b), Pigeonhole 2.4.3 (0bf9ee48) -- from
>    Homebrew
>    - OS: macOS 15.6 (Sequoia, Darwin 24.6.0, arm64/Apple Silicon, APFS)
>    - Mail client: Mozilla Thunderbird 149.0.2
>    - Dovecot started via `sudo brew services start dovecot` (launchd)
>    ## Reproducing
>    1. Fresh macOS install of Dovecot 2.4.3 via Homebrew.
>    2. Configure a minimal single-user IMAP setup with `passdb static` /
>       `userdb static`, SSL on port 993 with a self-signed cert, Maildir
>       storage (config at end of this mail).
>    3. Start Dovecot as root via launchd (`sudo brew services start dovecot`).
>    4. Connect any IMAP client to localhost:993 (I used Thunderbird 149 with a
>       permanent cert exception for the self-signed certificate).
>    5. The client hangs / reports "server closed the connection" / sees no
>       folders.
>    6. `dovecot.log` fills with repeated entries like the following:
>    ```
>    anvil: Warning: conn unix:anvil (uid=0): Handshake with duplicate
>    service=imap-login pid=-1 - replacing the old connection

As workaround, you probably want to disable anvil usage. Your problem seems to be that pids are -1. That sounds like there is some problem with pids, maybe sandbox or some other filter? Did this work with 2.4.2?

Aki

_______________________________________________
dovecot mailing list -- [email protected]
To unsubscribe send an email to [email protected]