[libvirt] [PATCH 1/2] apparmor: Allow access to filesystem mounts

[Felix Geyer]

Make virt-aa-helper create rules to allow VMs access to filesystem
mounts from the host.
---
 src/security/virt-aa-helper.c | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/src/security/virt-aa-helper.c b/src/security/virt-aa-helper.c
index b9282b4..e1f7848 100644
--- a/src/security/virt-aa-helper.c
+++ b/src/security/virt-aa-helper.c
@@ -578,9 +578,6 @@ valid_path(const char *path, const bool readonly)
             return -1;
 
         switch (sb.st_mode & S_IFMT) {
-            case S_IFDIR:
-                return 1;
-                break;
             case S_IFSOCK:
                 return 1;
                 break;
@@ -747,7 +744,7 @@ get_definition(vahControl * ctl, const char *xmlStr)
 }
 
 static int
-vah_add_file(virBufferPtr buf, const char *path, const char *perms)
+vah_add_path(virBufferPtr buf, const char *path, const char *perms, bool recursive)
 {
     char *tmp = NULL;
     int rc = -1;
@@ -788,10 +785,14 @@ vah_add_file(virBufferPtr buf, const char *path, const char *perms)
         goto cleanup;
     }
 
-    virBufferAsprintf(buf, "  \"%s\" %s,\n", tmp, perms);
+    virBufferAsprintf(buf, "  \"%s%s\" %s,\n", tmp, recursive ? "/**" : "", perms);
     if (readonly) {
         virBufferAddLit(buf, "  # don't audit writes to readonly files\n");
-        virBufferAsprintf(buf, "  deny \"%s\" w,\n", tmp);
+        virBufferAsprintf(buf, "  deny \"%s%s\" w,\n", tmp, recursive ? "/**" : "");
+    }
+    if (recursive) {
+        // allow reading (but not creating) the dir
+        virBufferAsprintf(buf, "  \"%s/\" r,\n", tmp);
     }
 
   cleanup:
@@ -801,6 +802,12 @@ vah_add_file(virBufferPtr buf, const char *path, const char *perms)
 }
 
 static int
+vah_add_file(virBufferPtr buf, const char *path, const char *perms)
+{
+    return vah_add_path(buf, path, perms, false);
+}
+
+static int
 vah_add_file_chardev(virBufferPtr buf,
                      const char *path,
                      const char *perms,
@@ -1049,6 +1056,13 @@ get_files(vahControl * ctl)
             } /* switch */
         }
 
+    for (i = 0; i < ctl->def->nfss; i++) {
+        virDomainFSDefPtr fs = ctl->def->fss[i];
+
+        if (vah_add_path(&buf, fs->src, fs->readonly ? "r" : "rw", true) != 0)
+            goto cleanup;
+    }
+
     if (ctl->newfile)
         if (vah_add_file(&buf, ctl->newfile, "rw") != 0)
             goto cleanup;
-- 
1.8.5.3