summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorFelipe Sateler <fsateler@users.noreply.github.com>2016-08-22 16:40:58 -0300
committerEvgeny Vereshchagin <evvers@ya.ru>2016-08-22 22:40:58 +0300
commit83f12b27d14853e7c89a326f7cd31a6c739d378e (patch)
treea422aeadd910a844174690dea8e415069e799470
parent05b4d3b55c0a60aa17817d51129f2bc83914c1f4 (diff)
core: do not fail at step SECCOMP if there is no kernel support (#4004)
Fixes #3882
-rw-r--r--src/core/execute.c38
-rw-r--r--src/core/main.c6
-rw-r--r--src/shared/seccomp-util.c10
-rw-r--r--src/shared/seccomp-util.h2
-rw-r--r--src/test/test-execute.c11
5 files changed, 58 insertions, 9 deletions
diff --git a/src/core/execute.c b/src/core/execute.c
index 0af8eb5a02..55f15d7e49 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -1074,7 +1074,17 @@ static void rename_process_from_path(const char *path) {
#ifdef HAVE_SECCOMP
-static int apply_seccomp(const ExecContext *c) {
+static bool skip_seccomp_unavailable(const Unit* u, const char* msg) {
+ if (!is_seccomp_available()) {
+ log_open();
+ log_unit_debug(u, "SECCOMP not detected in the kernel, skipping %s", msg);
+ log_close();
+ return true;
+ }
+ return false;
+}
+
+static int apply_seccomp(const Unit* u, const ExecContext *c) {
uint32_t negative_action, action;
scmp_filter_ctx *seccomp;
Iterator i;
@@ -1083,6 +1093,9 @@ static int apply_seccomp(const ExecContext *c) {
assert(c);
+ if (skip_seccomp_unavailable(u, "syscall filtering"))
+ return 0;
+
negative_action = c->syscall_errno == 0 ? SCMP_ACT_KILL : SCMP_ACT_ERRNO(c->syscall_errno);
seccomp = seccomp_init(c->syscall_whitelist ? negative_action : SCMP_ACT_ALLOW);
@@ -1123,13 +1136,16 @@ finish:
return r;
}
-static int apply_address_families(const ExecContext *c) {
+static int apply_address_families(const Unit* u, const ExecContext *c) {
scmp_filter_ctx *seccomp;
Iterator i;
int r;
assert(c);
+ if (skip_seccomp_unavailable(u, "RestrictAddressFamilies="))
+ return 0;
+
seccomp = seccomp_init(SCMP_ACT_ALLOW);
if (!seccomp)
return -ENOMEM;
@@ -1244,12 +1260,15 @@ finish:
return r;
}
-static int apply_memory_deny_write_execute(const ExecContext *c) {
+static int apply_memory_deny_write_execute(const Unit* u, const ExecContext *c) {
scmp_filter_ctx *seccomp;
int r;
assert(c);
+ if (skip_seccomp_unavailable(u, "MemoryDenyWriteExecute="))
+ return 0;
+
seccomp = seccomp_init(SCMP_ACT_ALLOW);
if (!seccomp)
return -ENOMEM;
@@ -1283,7 +1302,7 @@ finish:
return r;
}
-static int apply_restrict_realtime(const ExecContext *c) {
+static int apply_restrict_realtime(const Unit* u, const ExecContext *c) {
static const int permitted_policies[] = {
SCHED_OTHER,
SCHED_BATCH,
@@ -1296,6 +1315,9 @@ static int apply_restrict_realtime(const ExecContext *c) {
assert(c);
+ if (skip_seccomp_unavailable(u, "RestrictRealtime="))
+ return 0;
+
seccomp = seccomp_init(SCMP_ACT_ALLOW);
if (!seccomp)
return -ENOMEM;
@@ -2403,7 +2425,7 @@ static int exec_child(
#ifdef HAVE_SECCOMP
if (use_address_families) {
- r = apply_address_families(context);
+ r = apply_address_families(unit, context);
if (r < 0) {
*exit_status = EXIT_ADDRESS_FAMILIES;
return r;
@@ -2411,7 +2433,7 @@ static int exec_child(
}
if (context->memory_deny_write_execute) {
- r = apply_memory_deny_write_execute(context);
+ r = apply_memory_deny_write_execute(unit, context);
if (r < 0) {
*exit_status = EXIT_SECCOMP;
return r;
@@ -2419,7 +2441,7 @@ static int exec_child(
}
if (context->restrict_realtime) {
- r = apply_restrict_realtime(context);
+ r = apply_restrict_realtime(unit, context);
if (r < 0) {
*exit_status = EXIT_SECCOMP;
return r;
@@ -2427,7 +2449,7 @@ static int exec_child(
}
if (use_syscall_filter) {
- r = apply_seccomp(context);
+ r = apply_seccomp(unit, context);
if (r < 0) {
*exit_status = EXIT_SECCOMP;
return r;
diff --git a/src/core/main.c b/src/core/main.c
index 125cfb28f0..7d8322ebd8 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -72,6 +72,9 @@
#include "process-util.h"
#include "raw-clone.h"
#include "rlimit-util.h"
+#ifdef HAVE_SECCOMP
+#include "seccomp-util.h"
+#endif
#include "selinux-setup.h"
#include "selinux-util.h"
#include "signal-util.h"
@@ -1186,6 +1189,9 @@ static int enforce_syscall_archs(Set *archs) {
void *id;
int r;
+ if (!is_seccomp_available())
+ return 0;
+
seccomp = seccomp_init(SCMP_ACT_ALLOW);
if (!seccomp)
return log_oom();
diff --git a/src/shared/seccomp-util.c b/src/shared/seccomp-util.c
index 8656d112b8..4667f508c7 100644
--- a/src/shared/seccomp-util.c
+++ b/src/shared/seccomp-util.c
@@ -21,6 +21,8 @@
#include <seccomp.h>
#include <stddef.h>
+#include "alloc-util.h"
+#include "fileio.h"
#include "macro.h"
#include "seccomp-util.h"
#include "string-util.h"
@@ -89,6 +91,14 @@ int seccomp_add_secondary_archs(scmp_filter_ctx *c) {
}
+bool is_seccomp_available(void) {
+ _cleanup_free_ char* field = NULL;
+ static int cached_enabled = -1;
+ if (cached_enabled < 0)
+ cached_enabled = get_proc_field("/proc/self/status", "Seccomp", "\n", &field) == 0;
+ return cached_enabled;
+}
+
const SystemCallFilterSet syscall_filter_sets[] = {
{
/* Clock */
diff --git a/src/shared/seccomp-util.h b/src/shared/seccomp-util.h
index be33eecb85..cca7c17912 100644
--- a/src/shared/seccomp-util.h
+++ b/src/shared/seccomp-util.h
@@ -27,6 +27,8 @@ int seccomp_arch_from_string(const char *n, uint32_t *ret);
int seccomp_add_secondary_archs(scmp_filter_ctx *c);
+bool is_seccomp_available(void);
+
typedef struct SystemCallFilterSet {
const char *set_name;
const char *value;
diff --git a/src/test/test-execute.c b/src/test/test-execute.c
index 1d24115b5c..05ec1d2eb1 100644
--- a/src/test/test-execute.c
+++ b/src/test/test-execute.c
@@ -30,6 +30,9 @@
#include "mkdir.h"
#include "path-util.h"
#include "rm-rf.h"
+#ifdef HAVE_SECCOMP
+#include "seccomp-util.h"
+#endif
#include "test-helper.h"
#include "unit.h"
#include "util.h"
@@ -132,21 +135,27 @@ static void test_exec_privatedevices(Manager *m) {
static void test_exec_systemcallfilter(Manager *m) {
#ifdef HAVE_SECCOMP
+ if (!is_seccomp_available())
+ return;
test(m, "exec-systemcallfilter-not-failing.service", 0, CLD_EXITED);
test(m, "exec-systemcallfilter-not-failing2.service", 0, CLD_EXITED);
test(m, "exec-systemcallfilter-failing.service", SIGSYS, CLD_KILLED);
test(m, "exec-systemcallfilter-failing2.service", SIGSYS, CLD_KILLED);
+
#endif
}
static void test_exec_systemcallerrornumber(Manager *m) {
#ifdef HAVE_SECCOMP
- test(m, "exec-systemcallerrornumber.service", 1, CLD_EXITED);
+ if (is_seccomp_available())
+ test(m, "exec-systemcallerrornumber.service", 1, CLD_EXITED);
#endif
}
static void test_exec_systemcall_system_mode_with_user(Manager *m) {
#ifdef HAVE_SECCOMP
+ if (!is_seccomp_available())
+ return;
if (getpwnam("nobody"))
test(m, "exec-systemcallfilter-system-user.service", 0, CLD_EXITED);
else if (getpwnam("nfsnobody"))