From c5e142b3b9bc25ed508b8b7b62907ed99daba84d Mon Sep 17 00:00:00 2001

Message-Id: <c5e142b3b9bc25ed508b8b7b62907ed99daba84d@dist-git>

From: Michal Privoznik <mprivozn@redhat.com>

Date: Thu, 11 May 2017 15:38:40 +0200

Subject: [PATCH] qemuDomainAttachDeviceMknodRecursive: Don't try to create

 devices under preserved mount points

https://bugzilla.redhat.com/show_bug.cgi?id=1449510

Just like in previous commit, this fixes the same issue for

hotplug.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

Reviewed-by: Cedric Bosdonnat <cbosdonnat@suse.com>

(cherry picked from commit b3418f36be75eb4bdecd6aa37cda7a268519ee46)

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/qemu/qemu_domain.c | 114 ++++++++++++++++++++++++++++++++++++++++++-------

 1 file changed, 98 insertions(+), 16 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c

index 9217747d5..671569f6f 100644

--- a/src/qemu/qemu_domain.c

+++ b/src/qemu/qemu_domain.c

@@ -8314,6 +8314,8 @@ static int

 qemuDomainAttachDeviceMknodRecursive(virQEMUDriverPtr driver,

                                      virDomainObjPtr vm,

                                      const char *file,

+                                     char * const *devMountsPath,

+                                     size_t ndevMountsPath,

                                      unsigned int ttl)

 {

     struct qemuDomainAttachDeviceMknodData data;

@@ -8391,20 +8393,36 @@ qemuDomainAttachDeviceMknodRecursive(virQEMUDriverPtr driver,

 #endif

     if (STRPREFIX(file, DEVPREFIX)) {

-        if (qemuSecurityPreFork(driver->securityManager) < 0)

-            goto cleanup;

+        size_t i;

-        if (virProcessRunInMountNamespace(vm->pid,

-                                          qemuDomainAttachDeviceMknodHelper,

-                                          &data) < 0) {

-            qemuSecurityPostFork(driver->securityManager);

-            goto cleanup;

+        for (i = 0; i < ndevMountsPath; i++) {

+            if (STREQ(devMountsPath[i], "/dev"))

+                continue;

+            if (STRPREFIX(file, devMountsPath[i]))

+                break;

+        }

+

+        if (i == ndevMountsPath) {

+            if (qemuSecurityPreFork(driver->securityManager) < 0)

+                goto cleanup;

+

+            if (virProcessRunInMountNamespace(vm->pid,

+                                              qemuDomainAttachDeviceMknodHelper,

+                                              &data) < 0) {

+                qemuSecurityPostFork(driver->securityManager);

+                goto cleanup;

+            }

+            qemuSecurityPostFork(driver->securityManager);

+        } else {

+            VIR_DEBUG("Skipping dev %s because of %s mount point",

+                      file, devMountsPath[i]);

         }

-        qemuSecurityPostFork(driver->securityManager);

     }

     if (isLink &&

-        qemuDomainAttachDeviceMknodRecursive(driver, vm, target, ttl -1) < 0)

+        qemuDomainAttachDeviceMknodRecursive(driver, vm, target,

+                                             devMountsPath, ndevMountsPath,

+                                             ttl -1) < 0)

         goto cleanup;

     ret = 0;

@@ -8421,11 +8439,15 @@ qemuDomainAttachDeviceMknodRecursive(virQEMUDriverPtr driver,

 static int

 qemuDomainAttachDeviceMknod(virQEMUDriverPtr driver,

                             virDomainObjPtr vm,

-                            const char *file)

+                            const char *file,

+                            char * const *devMountsPath,

+                            size_t ndevMountsPath)

 {

     long symloop_max = sysconf(_SC_SYMLOOP_MAX);

-    return qemuDomainAttachDeviceMknodRecursive(driver, vm, file, symloop_max);

+    return qemuDomainAttachDeviceMknodRecursive(driver, vm, file,

+                                                devMountsPath, ndevMountsPath,

+                                                symloop_max);

 }

@@ -8465,6 +8487,9 @@ qemuDomainNamespaceSetupDisk(virQEMUDriverPtr driver,

                              virDomainObjPtr vm,

                              virStorageSourcePtr src)

 {

+    virQEMUDriverConfigPtr cfg = NULL;

+    char **devMountsPath = NULL;

+    size_t ndevMountsPath = 0;

     virStorageSourcePtr next;

     struct stat sb;

     int ret = -1;

@@ -8472,6 +8497,12 @@ qemuDomainNamespaceSetupDisk(virQEMUDriverPtr driver,

     if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))

         return 0;

+    cfg = virQEMUDriverGetConfig(driver);

+    if (qemuDomainGetPreservedMounts(cfg, vm,

+                                     &devMountsPath, NULL,

+                                     &ndevMountsPath) < 0)

+        goto cleanup;

+

     for (next = src; next; next = next->backingStore) {

         if (virStorageSourceIsEmpty(next) ||

             !virStorageSourceIsLocalStorage(next)) {

@@ -8490,12 +8521,15 @@ qemuDomainNamespaceSetupDisk(virQEMUDriverPtr driver,

         if (qemuDomainAttachDeviceMknod(driver,

                                         vm,

-                                        next->path) < 0)

+                                        next->path,

+                                        devMountsPath, ndevMountsPath) < 0)

             goto cleanup;

     }

     ret = 0;

  cleanup:

+    virStringListFreeCount(devMountsPath, ndevMountsPath);

+    virObjectUnref(cfg);

     return ret;

 }

@@ -8520,6 +8554,9 @@ qemuDomainNamespaceSetupHostdev(virQEMUDriverPtr driver,

                                 virDomainObjPtr vm,

                                 virDomainHostdevDefPtr hostdev)

 {

+    virQEMUDriverConfigPtr cfg = NULL;

+    char **devMountsPath = NULL;

+    size_t ndevMountsPath = 0;

     int ret = -1;

     char **path = NULL;

     size_t i, npaths = 0;

@@ -8530,10 +8567,17 @@ qemuDomainNamespaceSetupHostdev(virQEMUDriverPtr driver,

     if (qemuDomainGetHostdevPath(NULL, hostdev, false, &npaths, &path, NULL) < 0)

         goto cleanup;

+    cfg = virQEMUDriverGetConfig(driver);

+    if (qemuDomainGetPreservedMounts(cfg, vm,

+                                     &devMountsPath, NULL,

+                                     &ndevMountsPath) < 0)

+        goto cleanup;

+

     for (i = 0; i < npaths; i++) {

         if (qemuDomainAttachDeviceMknod(driver,

                                         vm,

-                                        path[i]) < 0)

+                                        path[i],

+                                        devMountsPath, ndevMountsPath) < 0)

         goto cleanup;

     }

@@ -8542,6 +8586,8 @@ qemuDomainNamespaceSetupHostdev(virQEMUDriverPtr driver,

     for (i = 0; i < npaths; i++)

         VIR_FREE(path[i]);

     VIR_FREE(path);

+    virStringListFreeCount(devMountsPath, ndevMountsPath);

+    virObjectUnref(cfg);

     return ret;

 }

@@ -8581,6 +8627,9 @@ qemuDomainNamespaceSetupMemory(virQEMUDriverPtr driver,

                                virDomainObjPtr vm,

                                virDomainMemoryDefPtr mem)

 {

+    virQEMUDriverConfigPtr cfg = NULL;

+    char **devMountsPath = NULL;

+    size_t ndevMountsPath = 0;

     int ret = -1;

     if (mem->model != VIR_DOMAIN_MEMORY_MODEL_NVDIMM)

@@ -8589,10 +8638,19 @@ qemuDomainNamespaceSetupMemory(virQEMUDriverPtr driver,

     if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))

         return 0;

-    if (qemuDomainAttachDeviceMknod(driver, vm, mem->nvdimmPath) < 0)

+    cfg = virQEMUDriverGetConfig(driver);

+    if (qemuDomainGetPreservedMounts(cfg, vm,

+                                     &devMountsPath, NULL,

+                                     &ndevMountsPath) < 0)

+        goto cleanup;

+

+    if (qemuDomainAttachDeviceMknod(driver, vm, mem->nvdimmPath,

+                                    devMountsPath, ndevMountsPath) < 0)

         goto cleanup;

     ret = 0;

  cleanup:

+    virStringListFreeCount(devMountsPath, ndevMountsPath);

+    virObjectUnref(cfg);

     return ret;

 }

@@ -8623,6 +8681,9 @@ qemuDomainNamespaceSetupChardev(virQEMUDriverPtr driver,

                                 virDomainObjPtr vm,

                                 virDomainChrDefPtr chr)

 {

+    virQEMUDriverConfigPtr cfg = NULL;

+    char **devMountsPath = NULL;

+    size_t ndevMountsPath = 0;

     const char *path;

     int ret = -1;

@@ -8634,12 +8695,21 @@ qemuDomainNamespaceSetupChardev(virQEMUDriverPtr driver,

     path = chr->source->data.file.path;

+    cfg = virQEMUDriverGetConfig(driver);

+    if (qemuDomainGetPreservedMounts(cfg, vm,

+                                     &devMountsPath, NULL,

+                                     &ndevMountsPath) < 0)

+        goto cleanup;

+

     if (qemuDomainAttachDeviceMknod(driver,

                                     vm,

-                                    path) < 0)

+                                    path,

+                                    devMountsPath, ndevMountsPath) < 0)

         goto cleanup;

     ret = 0;

  cleanup:

+    virStringListFreeCount(devMountsPath, ndevMountsPath);

+    virObjectUnref(cfg);

     return ret;

 }

@@ -8674,6 +8744,9 @@ qemuDomainNamespaceSetupRNG(virQEMUDriverPtr driver,

                             virDomainObjPtr vm,

                             virDomainRNGDefPtr rng)

 {

+    virQEMUDriverConfigPtr cfg = NULL;

+    char **devMountsPath = NULL;

+    size_t ndevMountsPath = 0;

     const char *path = NULL;

     int ret = -1;

@@ -8691,12 +8764,21 @@ qemuDomainNamespaceSetupRNG(virQEMUDriverPtr driver,

         goto cleanup;

     }

+    cfg = virQEMUDriverGetConfig(driver);

+    if (qemuDomainGetPreservedMounts(cfg, vm,

+                                     &devMountsPath, NULL,

+                                     &ndevMountsPath) < 0)

+        goto cleanup;

+

     if (qemuDomainAttachDeviceMknod(driver,

                                     vm,

-                                    path) < 0)

+                                    path,

+                                    devMountsPath, ndevMountsPath) < 0)

         goto cleanup;

     ret = 0;

  cleanup:

+    virStringListFreeCount(devMountsPath, ndevMountsPath);

+    virObjectUnref(cfg);

     return ret;

 }

-- 

2.13.0