We previously didn't bother to check the return values from any librpm
calls. In some cases where possibly the RPM database is faulty, this
caused us to return a zero-length list of installed applications (but
no error indication).
One way to reproduce this is given below. Note this reproducer will
only work when run on a RHEL 8 host (or more specifically, with
rpm <= 4.16):
$ virt-builder fedora-28
$ guestfish -a fedora-28.img -i rm /var/lib/rpm/Packages
$ guestfish --ro -a fedora-28.img -i inspect-list-applications /dev/sda4 -vx
...
chroot: /sysroot: running 'librpm'
error: cannot open Packages index using db5 - Read-only file system (30)
error: cannot open Packages database in
error: cannot open Packages index using db5 - Read-only file system (30)
error: cannot open Packages database in
librpm returned 0 installed packages
...
With this commit we get an error instead:
...
chroot: /sysroot: running 'librpm'
error: cannot open Packages index using db5 - Read-only file system (30)
error: cannot open Packages database in
ocaml_exn: 'internal_list_rpm_applications' raised 'Failure' exception
guestfsd: error: rpmtsInitIterator
guestfsd: => internal_list_rpm_applications (0x1fe) took 0.01 secs
libguestfs: trace: internal_list_rpm_applications = NULL (error)
libguestfs: error: internal_list_rpm_applications: rpmtsInitIterator
libguestfs: trace: inspect_list_applications2 = NULL (error)
libguestfs: trace: inspect_list_applications = NULL (error)
...
Not in this case, but in some cases of corrupt RPM databases it is
possible to recover them by running "rpmdb --rebuilddb" as a guest
command (ie. with guestfs_sh).
See-also: https://bugzilla.redhat.com/show_bug.cgi?id=2089623#c12
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2089623
Fixes: commit c9ee831aff
Reported-by: Xiaodai Wang
Reported-by: Ming Xie
Acked-by: Laszlo Ersek <lersek@redhat.com>
488245ed6c