Commit Graph

7 Commits

Author SHA1 Message Date
Peng Liang
bc16c1bcf6 qemu: Remove unused includes
Signed-off-by: Peng Liang <tcx4c70@gmail.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2022-06-16 06:43:57 +02:00
Kristina Hanicova
c39757f700 qemu: Do not erase duplicate devices from namespace if error occurs
If the attempt to attach a device failed, we erased the
unattached device from the namespace. This resulted in erasing an
already attached device in case of a duplicate. We need to check
for existing file in the namespace in order to determine erasing
it in case of a failure.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1780508

Signed-off-by: Kristina Hanicova <khanicov@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-07-15 12:00:24 +02:00
Michal Privoznik
c8238579fb lib: Drop internal virXXXPtr typedefs
Historically, we declared pointer type to our types:

  typedef struct _virXXX virXXX;
  typedef virXXX *virXXXPtr;

But usefulness of such declaration is questionable, at best.
Unfortunately, we can't drop every such declaration - we have to
carry some over, because they are part of public API (e.g.
virDomainPtr). But for internal types - we can do drop them and
use what every other C project uses 'virXXX *'.

This change was generated by a very ugly shell script that
generated sed script which was then called over each file in the
repository. For the shell script refer to the cover letter:

https://listman.redhat.com/archives/libvir-list/2021-March/msg00537.html

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2021-04-13 17:00:38 +02:00
Michal Privoznik
9048dc4e62 qemuDomainBuildNamespace: Populate basic /dev from daemon's namespace
As mentioned in previous commit, populating domain's namespace
from pre-exec() hook is dangerous. This commit moves population
of the namespace with basic /dev nodes (e.g. /dev/null, /dev/kvm,
etc.) into daemon's namespace.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:36 +02:00
Michal Privoznik
8da362fe62 qemu_domain_namespace: Repurpose qemuDomainBuildNamespace()
Okay, here is the deal. Currently, the way we build namespace is
very fragile. It is done from pre-exec hook when starting a
domain, after we mass closed all FDs and before we drop
privileges and exec() QEMU. This fact poses some limitations onto
the namespace build code, e.g. it has to make sure not to keep
any FD opened (not even through a library call), because it would
be leaked to QEMU. Also, it has to call only async signal safe
functions. These requirements are hard to meet - in fact as of my
commit v6.2.0-rc1~235 we are leaking a FD into QEMU by calling
libdevmapper functions.

To solve this issue and avoid similar problems in the future, we
should change our paradigm. We already have functions which can
populate domain's namespace with nodes from the daemon context.
If we use them to populate the namespace and keep only the bare
minimum in the pre-exec hook, we've mitigated the risk.

Therefore, the old qemuDomainBuildNamespace() is renamed to
qemuDomainUnshareNamespace() and new qemuDomainBuildNamespace()
function is introduced. So far, the new function is basically a
NOP and domain's namespace is still populated from the pre-exec
hook - next patches will fix it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:36 +02:00
Michal Privoznik
764eaf1aa4 qemu_domain_namespace: Rename qemuDomainCreateNamespace()
The name of this function is not very helpful, because it doesn't
create anything, it just flips a bit in a bitmask when domain is
starting up. Move the function internals into qemu_process.c and
forget the function ever existed.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:40:33 +02:00
Michal Privoznik
90eee87569 qemu: Separate out namespace handling code
The qemu_domain.c file is big as is and we should split it into
separate semantic blocks. Start with code that handles domain
namespaces.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-08-03 19:32:27 +02:00