X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fcore%2Fnamespace.c;h=f76d3891c387678cb4bac5f4b75a2588341b9d39;hb=671174136525ddf208cdbe75d6d6bd159afa961f;hp=f11065ee4bdade83d78373d7f4bb09cfda15723a;hpb=d6797c920e9eb70f46a893c00fdd9ecb86d15f84;p=elogind.git diff --git a/src/core/namespace.c b/src/core/namespace.c index f11065ee4..f76d3891c 100644 --- a/src/core/namespace.c +++ b/src/core/namespace.c @@ -42,6 +42,7 @@ #include "mkdir.h" #include "dev-setup.h" #include "def.h" +#include "label.h" typedef enum MountMode { /* This is ordered by priority! */ @@ -50,6 +51,7 @@ typedef enum MountMode { PRIVATE_TMP, PRIVATE_VAR_TMP, PRIVATE_DEV, + PRIVATE_BUS_ENDPOINT, READWRITE } MountMode; @@ -68,6 +70,7 @@ static int append_mounts(BindMount **p, char **strv, MountMode mode) { STRV_FOREACH(i, strv) { (*p)->ignore = false; + (*p)->done = false; if ((mode == INACCESSIBLE || mode == READONLY || mode == READWRITE) && (*i)[0] == '-') { (*p)->ignore = true; @@ -122,8 +125,7 @@ static void drop_duplicates(BindMount *m, unsigned *n) { if (previous && path_equal(f->path, previous->path)) continue; - t->path = f->path; - t->mode = f->mode; + *t = *f; previous = t; @@ -223,7 +225,10 @@ static int mount_dev(BindMount *m) { goto fail; } + label_context_set(d, st.st_mode); r = mknod(dn, st.st_mode, st.st_rdev); + label_context_clear(); + if (r < 0) { r = -errno; goto fail; @@ -268,6 +273,84 @@ fail: return r; } +static int mount_kdbus(BindMount *m) { + + char temporary_mount[] = "/tmp/kdbus-dev-XXXXXX"; + _cleanup_free_ char *basepath = NULL; + _cleanup_umask_ mode_t u; + char *busnode = NULL, *root; + struct stat st; + int r; + + assert(m); + + u = umask(0000); + + if (!mkdtemp(temporary_mount)) { + log_error("Failed create temp dir: %m"); + return -errno; + } + + root = strappenda(temporary_mount, "/kdbus"); + mkdir(root, 0755); + if (mount("tmpfs", root, "tmpfs", MS_NOSUID|MS_STRICTATIME, "mode=777") < 0) { + r = -errno; + goto fail; + } + + /* create a new /dev/null dev node copy so we have some fodder to + * bind-mount the custom endpoint over. */ + if (stat("/dev/null", &st) < 0) { + log_error("Failed to stat /dev/null: %m"); + r = -errno; + goto fail; + } + + busnode = strappenda(root, "/bus"); + if (mknod(busnode, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0) { + log_error("mknod() for %s failed: %m", busnode); + r = -errno; + goto fail; + } + + r = mount(m->path, busnode, "bind", MS_BIND, NULL); + if (r < 0) { + log_error("bind mount of %s failed: %m", m->path); + r = -errno; + goto fail; + } + + basepath = dirname_malloc(m->path); + if (!basepath) { + r = -ENOMEM; + goto fail; + } + + if (mount(root, basepath, NULL, MS_MOVE, NULL) < 0) { + log_error("bind mount of %s failed: %m", basepath); + r = -errno; + goto fail; + } + + rmdir(temporary_mount); + return 0; + +fail: + if (busnode) { + umount(busnode); + unlink(busnode); + } + + if (root) { + umount(root); + rmdir(root); + } + + rmdir(temporary_mount); + + return r; +} + static int apply_mount( BindMount *m, const char *tmp_dir, @@ -307,6 +390,9 @@ static int apply_mount( case PRIVATE_DEV: return mount_dev(m); + case PRIVATE_BUS_ENDPOINT: + return mount_kdbus(m); + default: assert_not_reached("Unknown mode"); } @@ -329,7 +415,7 @@ static int make_read_only(BindMount *m) { if (IN_SET(m->mode, INACCESSIBLE, READONLY)) r = bind_remount_recursive(m->path, true); - else if (m->mode == READWRITE) + else if (IN_SET(m->mode, READWRITE, PRIVATE_TMP, PRIVATE_VAR_TMP, PRIVATE_DEV)) r = bind_remount_recursive(m->path, false); else r = 0; @@ -346,6 +432,7 @@ int setup_namespace( char** inaccessible_dirs, char* tmp_dir, char* var_tmp_dir, + char* bus_endpoint_path, bool private_dev, ProtectHome protect_home, ProtectSystem protect_system, @@ -361,17 +448,17 @@ int setup_namespace( if (unshare(CLONE_NEWNS) < 0) return -errno; - n = !!tmp_dir + !!var_tmp_dir + + n = !!tmp_dir + !!var_tmp_dir + !!bus_endpoint_path + strv_length(read_write_dirs) + strv_length(read_only_dirs) + strv_length(inaccessible_dirs) + private_dev + (protect_home != PROTECT_HOME_NO ? 3 : 0) + - (protect_system != PROTECT_SYSTEM_NO ? 1 : 0) + + (protect_system != PROTECT_SYSTEM_NO ? 2 : 0) + (protect_system == PROTECT_SYSTEM_FULL ? 1 : 0); if (n > 0) { - m = mounts = (BindMount *) alloca(n * sizeof(BindMount)); + m = mounts = (BindMount *) alloca0(n * sizeof(BindMount)); r = append_mounts(&m, read_write_dirs, READWRITE); if (r < 0) return r; @@ -402,6 +489,12 @@ int setup_namespace( m++; } + if (bus_endpoint_path) { + m->path = bus_endpoint_path; + m->mode = PRIVATE_BUS_ENDPOINT; + m++; + } + if (protect_home != PROTECT_HOME_NO) { r = append_mounts(&m, STRV_MAKE("-/home", "-/run/user", "-/root"), protect_home == PROTECT_HOME_READ_ONLY ? READONLY : INACCESSIBLE); if (r < 0) @@ -409,7 +502,7 @@ int setup_namespace( } if (protect_system != PROTECT_SYSTEM_NO) { - r = append_mounts(&m, protect_system == PROTECT_SYSTEM_FULL ? STRV_MAKE("/usr", "/etc") : STRV_MAKE("/usr"), READONLY); + r = append_mounts(&m, protect_system == PROTECT_SYSTEM_FULL ? STRV_MAKE("/usr", "-/boot", "/etc") : STRV_MAKE("/usr", "-/boot"), READONLY); if (r < 0) return r; }