Normally when a child process is started by libvirt, the SELinux label
of that process is set to virtd_t (plus an MCS range). In at least one
case (passt) we need for the SELinux label of a child process label to
match the label that the binary would have transitioned to
automatically if it had been run standalone (in the case of passt,
that label is passt_t).
This patch modifies virSecuritySELinuxSetChildProcessLabel() (and all
the functions above it in the call chain) so that the toplevel
function can set a new argument "useBinarySpecificLabel" to true. If
it is true, then virSecuritySELinuxSetChildProcessLabel() will call
the new function virSecuritySELinuxContextSetFromFile(), which uses
the selinux library function security_compute_create() to determine
what would be the label of the new process if it had been run
standalone (rather than being run by libvirt) - the MCS range from the
normally-used label is added to this newly derived label, and that is
what is used for the new process rather than whatever is in the
domain's security label (which will usually be virtd_t).
In order to easily verify that nothing was broken by these changes to
the call chain, all callers currently set useBinarySpecificPath =
false, so all behavior should be completely unchanged. (The next
patch will set it to true only for the case of running passt.)
https://bugzilla.redhat.com/2172267
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When starting (some) external helpers, callers of
qemuSecurityCommandRun() pass &exitstatus variable, to learn the
exit code of helper process (with qemuTPMEmulatorStart() being
the only exception). Then, if the status wasn't zero they produce
a generic error message, like:
"Starting of helper process failed. exitstatus=%d"
or, in case of qemuPasstStart():
"Could not start 'passt': %s"
This is needless as virCommandRun() (that's called under the
hood), can do both for us, if NULL was passed instead of
@exitstatus. Not only it appends exit status, it also reads
stderr of failed command producing comprehensive error message:
Child process (${args}) unexpected exit status ${exitstatus}: ${stderr}
Therefore, pass NULL everywhere. But in contrast with one of
previous commits which removed @cmdret argument, there could be a
sensible caller which might want to process exit code. So keep
the argument for now and just pass NULL.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Every single caller of qemuSecurityCommandRun() calls the
function as:
if (qemuSecurityCommandRun(..., &cmdret) < 0)
goto cleanup;
if (cmdret < 0)
goto cleanup;
(modulo @exitstatus shenanigans)
Well, there's no need for such complication. There isn't a single
caller (and probably will never be (TM)), that would need to
distinguish the reason for the failure. Therefore,
qemuSecurityCommandRun() can be made to pass the retval of
virCommandRun() called under the hood.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The usual pattern when starting a helper daemon is:
if (qemuSecurityCommandRun(..., &exitstatus, &cmdret) < 0)
goto cleanup;
if (cmdret < 0 || exitstatus != 0) {
virReportError();
goto cleanup;
}
The only problem with this pattern is that if virCommandRun()
fails (i.e. cmdret < 0), then proper error was already reported.
But in this pattern we overwrite it (usually with less specific)
error.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The virCommand module is specifically designed so that no caller
has to check for retval of individual virCommand*() APIs except
for virCommandRun() where the actual error is reported. Moreover,
virCommandNew*() use g_new0() to allocate memory and thus it's
not really possible for those APIs to return NULL. Which is why
they are even marked as ATTRIBUTE_NONNULL. But there are few
places where we do check the retval which is a dead code
effectively. Drop those checks.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laine Stump <laine@redhat.com>
There's no real difference between
qemuSecurityStartVhostUserGPU() and qemuSecurityCommandRun(). The
latter is used more frequently while the former has just one
user. Therefore, drop the less frequently used one.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The binary validation in virPidFileReadPathIfAlive may fail with EACCES
if the calling process does not have CAP_SYS_PTRACE capability.
Therefore instead do only the check that the pidfile is locked by the
correct process.
Fixes the same issue as with swtpm.
Signed-off-by: Vasiliy Ulyanov <vulyanov@suse.de>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
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>
Historically, this file was a dump for most of our helper
functions and needed almost everywhere.
With the introduction of virfile.h and virstring.h,
and more importantly, virenum.h and the introduction
of GLib, that is no longer true.
Remove its include from C files that don't even use it.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
In two places where virPidFileForceCleanupPath() is called, we
try to unlink() the pidfile again. This is needless because
virPidFileForceCleanupPath() has done just that.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The caller doesn't care about the actual return value, so return -1
rather than errno.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Now that all the types using VIR_AUTOUNREF have a cleanup func defined
to virObjectUnref, use g_autoptr instead of VIR_AUTOUNREF.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Since commit 44e7f02915
util: rewrite auto cleanup macros to use glib's equivalent
VIR_AUTOPTR aliases to g_autoptr. Replace all of its use by the GLib
macro version.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Since commit 44e7f02915
util: rewrite auto cleanup macros to use glib's equivalent
VIR_AUTOFREE is just an alias for g_autofree. Use the GLib macros
directly instead of our custom aliases.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Similar to the qemu_tpm.c, add a unit with a few functions to
start/stop and setup the cgroup of the external vhost-user-gpu
process. See function documentation.
The vhost-user connection fd is set on qemuDomainVideoPrivate struct.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
