rsync: Update to 3.4.4

rsync: Update to 3.4.4

For details see:
https://download.samba.org/pub/rsync/NEWS#3.4.4

"NEWS for rsync 3.4.4 (8 Jun 2026)
Changes in this version:

This is a conservative point release that backports regression fixes on top
of 3.4.3. No new features are included.

BUG FIXES:

    Honour a relative alt-basis directory (e.g. --link-dest=../sibling,
    --copy-dest, --compare-dest) on a daemon receiver running with use
    chroot = no. Such a path is re-anchored at the module root but was then
    rejected by the receiver's secure open; it now works where
    kernel-enforced confinement is available. See the PORTABILITY note
    below for the platform limitation. Fixes #915.

    sender: open a module-root-absolute path for a path = / module so a
    daemon serving the filesystem root can satisfy absolute request paths
    again. Fixes #897.

    flist: accept the missing-args mode-0 entry in recv_file_entry. Fixes
    #910.

    receiver: fix a false "failed verification -⁠-⁠ update discarded" when
    resuming a delta transfer with an absolute --partial-dir.

    receiver: fix a NULL dereference on the delta discard path.

    generator: cap the block s2length at the negotiated checksum length.

    main: fix --mkpath with --dry-run for a file-to-file copy. Fixes #880.

    daemon: un-backslash escaped option args. Fixes #829.

    token: drain the matched-block insert deflate. Fixes #951.

    Fix the "update skips a file of a different type" case and the daemon
    upload delete stats.

    alloc: revert "zero all new memory from allocations". Fixes #959.

    Always clear the stat buffer and validate nanoseconds before use.

PORTABILITY / BUILD:

    The relative alt-basis fix for daemon receivers (#915) relies on kernel
    "stay below dirfd" path resolution -⁠-⁠ openat2(RESOLVE_BENEATH) on
    Linux 5.6+, or openat() with O_RESOLVE_BENEATH on FreeBSD 13+ and macOS
    15+. On platforms that lack it (Solaris, OpenBSD, NetBSD, Cygwin and
    older Linux) secure_relative_open() deliberately rejects any path with
    a .. component, so relative alt-basis directories remain unavailable
    there -⁠-⁠ function traded for safety, matching the trade-off already
    documented for the #715 fix. Absolute alt-basis paths are unaffected on
    every platform.

    openat2 is now autodetected at configure time (HAVE_OPENAT2): the
    openat2(RESOLVE_BENEATH) resolver is compiled in only when both
    <linux/openat2.h> and the SYS_openat2 syscall number are present,
    fixing the build on older kernels/headers. Fixes #924, #905, #900,
    #904.

    Fall back to do_mknod() when mknodat() / mkfifoat() are unavailable.
    Fixes #896.

    Install generated manpages correctly in an out-of-tree build.

DEVELOPER RELATED:

    Added a CI workflow that builds this stable branch and runs the
    v34-stable-testsuite regression suite against the built binary, giving
    regression coverage without importing the full master test suite into
    the stable branch.

    Added a check-progs target for fleettest and extended the build
    workflows to run on *-stable release branches."

Signed-off-by: Matthias Fischer <matthias.fischer@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>