execute: Create a random cgroup for each process

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/src/libpakfire/cgroup.c b/src/libpakfire/cgroup.c
index d68f58827201d4e64053f3eb611d692ad2c3b2bd..c57e68a58519978ece3d4623cff74c593f60c83c 100644 (file)
--- a/src/libpakfire/cgroup.c
+++ b/src/libpakfire/cgroup.c
@@ -25,6 +25,7 @@
 #include <signal.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/random.h>
 #include <sys/types.h>
 #include <sys/vfs.h>
 #include <time.h>
@@ -48,6 +49,33 @@ static const char* cgroup_controllers[] = {
        NULL,
 };
 
+static char random_character() {
+       static char characters[] =
+               "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+               "abcdefghijklmnopqrstuvwxyz"
+               "0123456789";
+
+       int random;
+
+       int r = getrandom(&random, sizeof(random), GRND_NONBLOCK);
+       if (r != sizeof(random))
+               return -1;
+
+       return characters[random % sizeof(characters)];
+}
+
+int pakfire_cgroup_random_name(char* template) {
+       for (int i = strlen(template) - 1; i > 0 && template[i] == 'X'; i--) {
+               char c = random_character();
+               if (c < 0)
+                       return 1;
+
+               template[i] = c;
+       }
+
+       return 0;
+}
+
 /*
        Returns the name of the parent group
 */

diff --git a/src/libpakfire/execute.c b/src/libpakfire/execute.c
index c2db04aeaf18e6022fa73afe5580e9949767ad46..75609143bfe3688d1d592bedd7acdf71e95f3023 100644 (file)
--- a/src/libpakfire/execute.c
+++ b/src/libpakfire/execute.c
@@ -265,6 +265,7 @@ static int pakfire_execute_fork(void* data) {
 
        DEBUG(pakfire, "Execution environment has been forked as PID %d\n", getpid());
        DEBUG(pakfire, "        root    : %s\n", root);
+       DEBUG(pakfire, "    cgroup  : %s\n", env->cgroup);
 
        for (unsigned int i = 0; env->argv[i]; i++)
                DEBUG(pakfire, "        argv[%u]        : %s\n", i, env->argv[i]);
@@ -340,11 +341,9 @@ PAKFIRE_EXPORT int pakfire_execute(Pakfire pakfire, const char* argv[], char* en
                .pakfire = pakfire,
                .argv = argv,
                .envp = envp,
+               .cgroup = "pakfire/execute-XXXXXX",
        };
 
-       // Make cgroup name
-       snprintf(env.cgroup, sizeof(env.cgroup) - 1, "%s", "pakfire/execute-XXXXXX");
-
        // argv is invalid
        if (!argv || !argv[0])
                return -EINVAL;
@@ -387,8 +386,13 @@ PAKFIRE_EXPORT int pakfire_execute(Pakfire pakfire, const char* argv[], char* en
                }
        }
 
+       // Make cgroup name
+       int r = pakfire_cgroup_random_name(env.cgroup);
+       if (r)
+               goto ERROR;
+
        // Create cgroup
-       int r = pakfire_cgroup_create(pakfire, env.cgroup);
+       r = pakfire_cgroup_create(pakfire, env.cgroup);
        if (r)
                goto ERROR;
 

diff --git a/src/libpakfire/include/pakfire/cgroup.h b/src/libpakfire/include/pakfire/cgroup.h
index b86150706e655f8d851bbaf116c74eba9dbbb18c..3ac6d441822b2ef6d7c995bcf27f173ab82dfce3 100644 (file)
--- a/src/libpakfire/include/pakfire/cgroup.h
+++ b/src/libpakfire/include/pakfire/cgroup.h
@@ -29,6 +29,8 @@
 
 #include <pakfire/types.h>
 
+int pakfire_cgroup_random_name(char* template);
+
 int pakfire_cgroup_create(Pakfire pakfire, const char* group);
 int pakfire_cgroup_destroy(Pakfire pakfire, const char* group);
 

diff --git a/tests/libpakfire/cgroup.c b/tests/libpakfire/cgroup.c
index 283cc0c6875308164791974b3e6f96bf17718a48..508614a3e4ec752bcf2a06f2f34169e496469477 100644 (file)
--- a/tests/libpakfire/cgroup.c
+++ b/tests/libpakfire/cgroup.c
@@ -163,11 +163,25 @@ static int test_cpustat(const struct test* t) {
        );
 }
 
+static int test_random_name(const struct test* t) {
+       char name1[] = "pakfire/execute-XXXXXX";
+       char name2[] = "pakfire/execute-XXXXXX";
+
+       ASSERT_SUCCESS(pakfire_cgroup_random_name(name1));
+       ASSERT_SUCCESS(pakfire_cgroup_random_name(name2));
+
+       // Make sure we got different results
+       ASSERT_STRING_NOT_EQUALS(name1, name2);
+
+       return EXIT_SUCCESS;
+}
+
 int main(int argc, char** argv) {
        testsuite_add_test(test_create_and_destroy);
        testsuite_add_test(test_attach);
        testsuite_add_test(test_killall);
        testsuite_add_test(test_cpustat);
+       testsuite_add_test(test_random_name);
 
        return testsuite_run();
 }

diff --git a/tests/testsuite.h b/tests/testsuite.h
index 2dcb842ae7825f121e0ffe5d214e3a5b9fb71bc2..d6a7b073d33f8bda33f46fdcce1070e5b960704a 100644 (file)
--- a/tests/testsuite.h
+++ b/tests/testsuite.h
@@ -85,6 +85,15 @@ int testsuite_run();
                } \
        } while (0)
 
+#define ASSERT_STRING_NOT_EQUALS(value1, value2) \
+       do { \
+               if (strcmp(value1, value2) == 0) { \
+                       LOG_ERROR("Failed assertion: " #value1 " (%s) != " #value2 " (%s) %s:%d %s\n", \
+                               value1, value2, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
+                       return EXIT_FAILURE; \
+               } \
+       } while (0)
+
 #define ASSERT_STRING_STARTSWITH(string, start) \
        do { \
                if (strncmp(string, start, strlen(start)) != 0) { \