chiark / gitweb /
terminal/sysview: introduce SETTLE events
[elogind.git] / src / nspawn / nspawn.c
index 08bfdcf4ed3a62f383594e0619def26c6326730a..c851fdd136991dde71057fc851b4d0ca7c3bcb81 100644 (file)
@@ -181,6 +181,7 @@ static ExposePort *arg_expose_ports = NULL;
 static char **arg_property = NULL;
 static uid_t arg_uid_shift = UID_INVALID, arg_uid_range = 0x10000U;
 static bool arg_userns = false;
+static int arg_kill_signal = 0;
 
 static void help(void) {
         printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
@@ -229,6 +230,7 @@ static void help(void) {
                "     --capability=CAP       In addition to the default, retain specified\n"
                "                            capability\n"
                "     --drop-capability=CAP  Drop the specified capability from the default set\n"
+               "     --kill-signal=SIGNAL   Select signal to use for shutting down PID 1\n"
                "     --link-journal=MODE    Link up guest journal, one of no, auto, guest, host,\n"
                "                            try-guest, try-host\n"
                "  -j                        Equivalent to --link-journal=try-guest\n"
@@ -293,6 +295,7 @@ static int parse_argv(int argc, char *argv[]) {
                 ARG_TEMPLATE,
                 ARG_PROPERTY,
                 ARG_PRIVATE_USERS,
+                ARG_KILL_SIGNAL,
         };
 
         static const struct option options[] = {
@@ -332,6 +335,7 @@ static int parse_argv(int argc, char *argv[]) {
                 { "port",                  required_argument, NULL, 'p'                   },
                 { "property",              required_argument, NULL, ARG_PROPERTY          },
                 { "private-users",         optional_argument, NULL, ARG_PRIVATE_USERS     },
+                { "kill-signal",           required_argument, NULL, ARG_KILL_SIGNAL       },
                 {}
         };
 
@@ -767,6 +771,15 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_userns = true;
                         break;
 
+                case ARG_KILL_SIGNAL:
+                        arg_kill_signal = signal_from_string_try_harder(optarg);
+                        if (arg_kill_signal < 0) {
+                                log_error("Cannot parse signal: %s", optarg);
+                                return -EINVAL;
+                        }
+
+                        break;
+
                 case '?':
                         return -EINVAL;
 
@@ -829,6 +842,9 @@ static int parse_argv(int argc, char *argv[]) {
 
         arg_retain = (arg_retain | plus | (arg_private_network ? 1ULL << CAP_NET_ADMIN : 0)) & ~minus;
 
+        if (arg_boot && arg_kill_signal <= 0)
+                arg_kill_signal = SIGRTMIN+3;
+
         return 1;
 }
 
@@ -2551,19 +2567,19 @@ static int setup_ipvlan(pid_t pid) {
 static int setup_seccomp(void) {
 
 #ifdef HAVE_SECCOMP
-        static const int blacklist[] = {
-                SCMP_SYS(kexec_load),
-                SCMP_SYS(open_by_handle_at),
-                SCMP_SYS(iopl),
-                SCMP_SYS(ioperm),
-                SCMP_SYS(swapon),
-                SCMP_SYS(swapoff),
-        };
-
-        static const int kmod_blacklist[] = {
-                SCMP_SYS(init_module),
-                SCMP_SYS(finit_module),
-                SCMP_SYS(delete_module),
+        static const struct {
+                uint64_t capability;
+                int syscall_num;
+        } blacklist[] = {
+                { CAP_SYS_RAWIO,  SCMP_SYS(iopl)},
+                { CAP_SYS_RAWIO,  SCMP_SYS(ioperm)},
+                { CAP_SYS_BOOT,   SCMP_SYS(kexec_load)},
+                { CAP_SYS_ADMIN,  SCMP_SYS(swapon)},
+                { CAP_SYS_ADMIN,  SCMP_SYS(swapoff)},
+                { CAP_SYS_ADMIN,  SCMP_SYS(open_by_handle_at)},
+                { CAP_SYS_MODULE, SCMP_SYS(init_module)},
+                { CAP_SYS_MODULE, SCMP_SYS(finit_module)},
+                { CAP_SYS_MODULE, SCMP_SYS(delete_module)},
         };
 
         scmp_filter_ctx seccomp;
@@ -2581,7 +2597,10 @@ static int setup_seccomp(void) {
         }
 
         for (i = 0; i < ELEMENTSOF(blacklist); i++) {
-                r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i], 0);
+                if (arg_retain & (1ULL << blacklist[i].capability))
+                        continue;
+
+                r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i].syscall_num, 0);
                 if (r == -EFAULT)
                         continue; /* unknown syscall */
                 if (r < 0) {
@@ -2590,19 +2609,6 @@ static int setup_seccomp(void) {
                 }
         }
 
-        /* If the CAP_SYS_MODULE capability is not requested then
-         * we'll block the kmod syscalls too */
-        if (!(arg_retain & (1ULL << CAP_SYS_MODULE))) {
-                for (i = 0; i < ELEMENTSOF(kmod_blacklist); i++) {
-                        r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), kmod_blacklist[i], 0);
-                        if (r == -EFAULT)
-                                continue; /* unknown syscall */
-                        if (r < 0) {
-                                log_error_errno(r, "Failed to block syscall: %m");
-                                goto finish;
-                        }
-                }
-        }
 
         /*
            Audit is broken in containers, much of the userspace audit
@@ -3559,7 +3565,7 @@ static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo
 
         pid = PTR_TO_UINT32(userdata);
         if (pid > 0) {
-                if (kill(pid, SIGRTMIN+3) >= 0) {
+                if (kill(pid, arg_kill_signal) >= 0) {
                         log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
                         sd_event_source_set_userdata(s, NULL);
                         return 0;
@@ -3729,7 +3735,7 @@ int main(int argc, char *argv[]) {
                 }
 
                 if (arg_ephemeral) {
-                        char *np;
+                        _cleanup_free_ char *np = NULL;
 
                         /* If the specified path is a mount point we
                          * generate the new snapshot immediately
@@ -3759,13 +3765,13 @@ int main(int argc, char *argv[]) {
 
                         r = btrfs_subvol_snapshot(arg_directory, np, arg_read_only, true);
                         if (r < 0) {
-                                free(np);
                                 log_error_errno(r, "Failed to create snapshot %s from %s: %m", np, arg_directory);
                                 goto finish;
                         }
 
                         free(arg_directory);
                         arg_directory = np;
+                        np = NULL;
 
                         remove_subvol = true;
 
@@ -4356,7 +4362,7 @@ int main(int argc, char *argv[]) {
                                         goto finish;
                                 }
 
-                                if (arg_boot) {
+                                if (arg_kill_signal > 0) {
                                         /* Try to kill the init system on SIGINT or SIGTERM */
                                         sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, UINT32_TO_PTR(pid));
                                         sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, UINT32_TO_PTR(pid));