[PATCH 0/2] qemu_cgroup: Two almost trivial cleanups
I'm trying to fix SGX patches I reviewed earlier [1] and these would simplify my attempts. 1: https://listman.redhat.com/archives/libvir-list/2022-July/232679.html Michal Prívozník (2): qemu_cgroup: Avoid ternary operator when setting @deviceACL qemu_cgroup: Introduce qemuCgroupAllowDevicesPaths() src/qemu/qemu_cgroup.c | 54 +++++++++++++++++++++++++++++------------- 1 file changed, 37 insertions(+), 17 deletions(-) -- 2.35.1
Inside of the qemuSetupDevicesCgroup() there's @deviceACL variable, which points to a string list of devices that are allowed in devices controller by default. This list can either come from qemu.conf (cfg->cgroupDeviceACL) or from a builtin @defaultDeviceACL. However, a multiline ternary operator is used when setting the variable which is against our coding style. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_cgroup.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index 2cc16a69d3..e012ba92c0 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -652,7 +652,7 @@ qemuSetupDevicesCgroup(virDomainObj *vm) { qemuDomainObjPrivate *priv = vm->privateData; g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(priv->driver); - const char *const *deviceACL = NULL; + const char *const *deviceACL = (const char *const *) cfg->cgroupDeviceACL; int rv = -1; size_t i; @@ -686,9 +686,8 @@ qemuSetupDevicesCgroup(virDomainObj *vm) if (rv < 0) return -1; - deviceACL = cfg->cgroupDeviceACL ? - (const char *const *)cfg->cgroupDeviceACL : - defaultDeviceACL; + if (!deviceACL) + deviceACL = defaultDeviceACL; if (vm->def->nsounds && ((!vm->def->ngraphics && cfg->nogfxAllowHostAudio) || -- 2.35.1
On Thu, Jul 21, 2022 at 12:31:41PM +0200, Michal Privoznik wrote:
Inside of the qemuSetupDevicesCgroup() there's @deviceACL variable, which points to a string list of devices that are allowed in devices controller by default. This list can either come from qemu.conf (cfg->cgroupDeviceACL) or from a builtin @defaultDeviceACL. However, a multiline ternary operator is used when setting the variable which is against our coding style.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
We have qemuCgroupAllowDevicePath() which sets up devices controller for just one path. And if we have more paths we have to call it in a loop. So far, we have just one such place, but soon we'll have another one (for SGX memory). Separate the loop into its own function so that it can be reused. And while at it, move setting the default set of devices as the first thing, right after all devices are disallowed. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_cgroup.c | 51 +++++++++++++++++++++++++++++------------- 1 file changed, 36 insertions(+), 15 deletions(-) diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index e012ba92c0..8339caeb53 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -67,6 +67,32 @@ qemuCgroupAllowDevicePath(virDomainObj *vm, } +static int +qemuCgroupAllowDevicesPaths(virDomainObj *vm, + const char *const *deviceACL, + int perms, + bool ignoreEacces) +{ + size_t i; + + for (i = 0; deviceACL[i] != NULL; i++) { + int rv; + + if (!virFileExists(deviceACL[i])) { + VIR_DEBUG("Ignoring non-existent device %s", deviceACL[i]); + continue; + } + + rv = qemuCgroupAllowDevicePath(vm, deviceACL[i], perms, ignoreEacces); + if (rv < 0 && + !virLastErrorIsSystemErrno(ENOENT)) + return -1; + } + + return 0; +} + + static int qemuCgroupDenyDevicePath(virDomainObj *vm, const char *path, @@ -659,6 +685,10 @@ qemuSetupDevicesCgroup(virDomainObj *vm) if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_DEVICES)) return 0; + deviceACL = cfg->cgroupDeviceACL ? + (const char *const *)cfg->cgroupDeviceACL : + defaultDeviceACL; + rv = virCgroupDenyAllDevices(priv->cgroup); virDomainAuditCgroup(vm, priv->cgroup, "deny", "all", rv == 0); if (rv < 0) { @@ -671,6 +701,12 @@ qemuSetupDevicesCgroup(virDomainObj *vm) return -1; } + if (!deviceACL) + deviceACL = defaultDeviceACL; + + if (qemuCgroupAllowDevicesPaths(vm, deviceACL, VIR_CGROUP_DEVICE_RW, false) < 0) + return -1; + if (qemuSetupFirmwareCgroup(vm) < 0) return -1; @@ -686,9 +722,6 @@ qemuSetupDevicesCgroup(virDomainObj *vm) if (rv < 0) return -1; - if (!deviceACL) - deviceACL = defaultDeviceACL; - if (vm->def->nsounds && ((!vm->def->ngraphics && cfg->nogfxAllowHostAudio) || (vm->def->graphics && @@ -703,18 +736,6 @@ qemuSetupDevicesCgroup(virDomainObj *vm) return -1; } - for (i = 0; deviceACL[i] != NULL; i++) { - if (!virFileExists(deviceACL[i])) { - VIR_DEBUG("Ignoring non-existent device %s", deviceACL[i]); - continue; - } - - rv = qemuCgroupAllowDevicePath(vm, deviceACL[i], VIR_CGROUP_DEVICE_RW, false); - if (rv < 0 && - !virLastErrorIsSystemErrno(ENOENT)) - return -1; - } - if (virDomainChrDefForeach(vm->def, true, qemuSetupChardevCgroupCB, -- 2.35.1
On 7/21/22 12:31, Michal Privoznik wrote:
We have qemuCgroupAllowDevicePath() which sets up devices controller for just one path. And if we have more paths we have to call it in a loop. So far, we have just one such place, but soon we'll have another one (for SGX memory). Separate the loop into its own function so that it can be reused.
And while at it, move setting the default set of devices as the first thing, right after all devices are disallowed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_cgroup.c | 51 +++++++++++++++++++++++++++++------------- 1 file changed, 36 insertions(+), 15 deletions(-)
diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index e012ba92c0..8339caeb53 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -67,6 +67,32 @@ qemuCgroupAllowDevicePath(virDomainObj *vm, }
+static int +qemuCgroupAllowDevicesPaths(virDomainObj *vm, + const char *const *deviceACL, + int perms, + bool ignoreEacces) +{ + size_t i; + + for (i = 0; deviceACL[i] != NULL; i++) { + int rv; + + if (!virFileExists(deviceACL[i])) { + VIR_DEBUG("Ignoring non-existent device %s", deviceACL[i]); + continue; + } + + rv = qemuCgroupAllowDevicePath(vm, deviceACL[i], perms, ignoreEacces); + if (rv < 0 && + !virLastErrorIsSystemErrno(ENOENT)) + return -1; + } + + return 0; +} + + static int qemuCgroupDenyDevicePath(virDomainObj *vm, const char *path, @@ -659,6 +685,10 @@ qemuSetupDevicesCgroup(virDomainObj *vm) if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_DEVICES)) return 0;
+ deviceACL = cfg->cgroupDeviceACL ? + (const char *const *)cfg->cgroupDeviceACL : + defaultDeviceACL; +
OOOps, this hunk does not belong here. I've screwed up conflict resolution. Consider fixed locally. Michal
On Thu, Jul 21, 2022 at 12:45:29PM +0200, Michal Prívozník wrote:
On 7/21/22 12:31, Michal Privoznik wrote:
We have qemuCgroupAllowDevicePath() which sets up devices controller for just one path. And if we have more paths we have to call it in a loop. So far, we have just one such place, but soon we'll have another one (for SGX memory). Separate the loop into its own function so that it can be reused.
And while at it, move setting the default set of devices as the first thing, right after all devices are disallowed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_cgroup.c | 51 +++++++++++++++++++++++++++++------------- 1 file changed, 36 insertions(+), 15 deletions(-)
diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index e012ba92c0..8339caeb53 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -67,6 +67,32 @@ qemuCgroupAllowDevicePath(virDomainObj *vm, }
+static int +qemuCgroupAllowDevicesPaths(virDomainObj *vm, + const char *const *deviceACL, + int perms, + bool ignoreEacces) +{ + size_t i; + + for (i = 0; deviceACL[i] != NULL; i++) { + int rv; + + if (!virFileExists(deviceACL[i])) { + VIR_DEBUG("Ignoring non-existent device %s", deviceACL[i]); + continue; + } + + rv = qemuCgroupAllowDevicePath(vm, deviceACL[i], perms, ignoreEacces); + if (rv < 0 && + !virLastErrorIsSystemErrno(ENOENT)) + return -1; + } + + return 0; +} + + static int qemuCgroupDenyDevicePath(virDomainObj *vm, const char *path, @@ -659,6 +685,10 @@ qemuSetupDevicesCgroup(virDomainObj *vm) if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_DEVICES)) return 0;
+ deviceACL = cfg->cgroupDeviceACL ? + (const char *const *)cfg->cgroupDeviceACL : + defaultDeviceACL; +
OOOps, this hunk does not belong here. I've screwed up conflict resolution. Consider fixed locally.
With this hunk removed Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
participants (3)
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Martin Kletzander -
Michal Privoznik -
Michal Prívozník