Package: exim4-base Version: 4.93-15 Severity: normal In /usr/share/doc/exim4-base/spec.txt.gz :
-------- In order to append to an NFS file safely from more than one host, it is necessary to take out a lock before opening the file, and the lock file achieves this. Otherwise, even with fcntl() locking, there is a risk of file corruption. -------- I don't see why. If used correctly, fcntl() locking should be sufficient under NFS. And if fcntl() locking is broken, lock files won't prevent corruption anyway: even if you have the lock, there is no guarantee that the client will synchronize the changes with the server before another process gets the lock and do changes (this is the problem I had with shared zsh history, which often got corrupted even though zsh used some form of locking... until I patched it in 2008 to use fcntl() locking). -- Package-specific info: Exim version 4.93 #5 built 25-Apr-2020 12:10:47 Copyright (c) University of Cambridge, 1995 - 2018 (c) The Exim Maintainers and contributors in ACKNOWLEDGMENTS file, 2007 - 2018 Berkeley DB: Berkeley DB 5.3.28: (September 9, 2013) Support for: crypteq iconv() IPv6 GnuTLS move_frozen_messages DANE DKIM DNSSEC Event I18N OCSP PRDR SOCKS TCP_Fast_Open Lookups (built-in): lsearch wildlsearch nwildlsearch iplsearch cdb dbm dbmjz dbmnz dnsdb dsearch nis nis0 passwd Authenticators: cram_md5 plaintext Routers: accept dnslookup ipliteral manualroute queryprogram redirect Transports: appendfile/maildir/mailstore autoreply lmtp pipe smtp Fixed never_users: 0 Configure owner: 0:0 Size of off_t: 8 Configuration file search path is /etc/exim4/exim4.conf:/var/lib/exim4/config.autogenerated Configuration file is /var/lib/exim4/config.autogenerated -- System Information: Debian Release: bullseye/sid APT prefers unstable-debug APT policy: (500, 'unstable-debug'), (500, 'stable-updates'), (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 5.4.0-4-amd64 (SMP w/12 CPU cores) Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE Locale: LANG=POSIX, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE=POSIX (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled Versions of packages exim4-base depends on: ii adduser 3.118 ii anacron 2.3-29 ii cron [cron-daemon] 3.0pl1-136 ii debconf [debconf-2.0] 1.5.74 ii exim4-config [exim4-config-2] 4.93-15 ii libc6 2.30-4 ii libdb5.3 5.3.28+dfsg1-0.6 ii lsb-base 11.1.0 ii netbase 6.1 ii systemd-sysv 245-2 Versions of packages exim4-base recommends: ii mailutils [mailx] 1:3.7-2.1 ii psmisc 23.3-1 Versions of packages exim4-base suggests: ii emacs-gtk [mail-reader] 1:26.3+1-1 pn exim4-doc-html | exim4-doc-info <none> pn eximon4 <none> ii file 1:5.38-4 ii gnutls-bin 3.6.13-2 ii mailutils [mail-reader] 1:3.7-2.1 ii mutt [mail-reader] 1.13.2-1 ii openssl 1.1.1g-1 pn spf-tools-perl <none> pn swaks <none> -- debconf information excluded -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
