The mount_entry_create_*_dirs() functions currently assume that the rootfs of the container is actually named "rootfs". This has the consequence that
del = strstr(lxcpath, "/rootfs"); if (!del) { free(lxcpath); lxc_free_array((void **)opts, free); return -1; } *del = '\0'; will return NULL when the rootfs of a container is not actually named "rootfs". This means the we return -1 and do not create the necessary upperdir/workdir directories required for the overlay/aufs mount to work. Hence, let's not make that assumption. We now pass lxc_path and lxc_name to mount_entry_create_*_dirs() and create the path directly. To prevent failure we also have mount_entry_create_*_dirs() check that lxc_name and lxc_path are not empty when they are passed in. Signed-off-by: Christian Brauner <christianvanbrau...@gmail.com> --- src/lxc/conf.c | 91 ++++++++++++++++++++++++++-------------------------------- 1 file changed, 41 insertions(+), 50 deletions(-) diff --git a/src/lxc/conf.c b/src/lxc/conf.c index 0e3421b..16a62f8 100644 --- a/src/lxc/conf.c +++ b/src/lxc/conf.c @@ -1816,20 +1816,22 @@ static void cull_mntent_opt(struct mntent *mntent) } static int mount_entry_create_overlay_dirs(const struct mntent *mntent, - const struct lxc_rootfs *rootfs) + const struct lxc_rootfs *rootfs, + const char *lxc_name, + const char *lxc_path) { - char *del = NULL; - char *lxcpath = NULL; + char lxcpath[MAXPATHLEN]; char *upperdir = NULL; char *workdir = NULL; char **opts = NULL; + int ret = 0; size_t arrlen = 0; size_t dirlen = 0; size_t i; size_t len = 0; size_t rootfslen = 0; - if (!rootfs->path) + if (!rootfs->path || !lxc_name || !lxc_path) return -1; opts = lxc_string_split(mntent->mnt_opts, ','); @@ -1845,19 +1847,11 @@ static int mount_entry_create_overlay_dirs(const struct mntent *mntent, workdir = opts[i] + len; } - lxcpath = strdup(rootfs->path); - if (!lxcpath) { - lxc_free_array((void **)opts, free); - return -1; - } - - del = strstr(lxcpath, "/rootfs"); - if (!del) { - free(lxcpath); + ret = snprintf(lxcpath, MAXPATHLEN, "%s/%s", lxc_path, lxc_name); + if (ret < 0 || ret >= MAXPATHLEN) { lxc_free_array((void **)opts, free); return -1; } - *del = '\0'; dirlen = strlen(lxcpath); rootfslen = strlen(rootfs->path); @@ -1877,25 +1871,26 @@ static int mount_entry_create_overlay_dirs(const struct mntent *mntent, WARN("Failed to create workdir"); } - free(lxcpath); lxc_free_array((void **)opts, free); return 0; } static int mount_entry_create_aufs_dirs(const struct mntent *mntent, - const struct lxc_rootfs *rootfs) + const struct lxc_rootfs *rootfs, + const char *lxc_name, + const char *lxc_path) { - char *del = NULL; - char *lxcpath = NULL; + char lxcpath[MAXPATHLEN]; char *scratch = NULL; char *tmp = NULL; char *upperdir = NULL; char **opts = NULL; + int ret = 0; size_t arrlen = 0; size_t i; size_t len = 0; - if (!rootfs->path) + if (!rootfs->path || !lxc_name || !lxc_path) return -1; opts = lxc_string_split(mntent->mnt_opts, ','); @@ -1919,19 +1914,11 @@ static int mount_entry_create_aufs_dirs(const struct mntent *mntent, return -1; } - lxcpath = strdup(rootfs->path); - if (!lxcpath) { - lxc_free_array((void **)opts, free); - return -1; - } - - del = strstr(lxcpath, "/rootfs"); - if (!del) { - free(lxcpath); + ret = snprintf(lxcpath, MAXPATHLEN, "%s/%s", lxc_path, lxc_name); + if (ret < 0 || ret >= MAXPATHLEN) { lxc_free_array((void **)opts, free); return -1; } - *del = '\0'; /* We neither allow users to create upperdirs outside the containerdir * nor inside the rootfs. The latter might be debatable. */ @@ -1940,23 +1927,24 @@ static int mount_entry_create_aufs_dirs(const struct mntent *mntent, WARN("Failed to create upperdir"); } - free(lxcpath); lxc_free_array((void **)opts, free); return 0; } + static int mount_entry_create_dir_file(const struct mntent *mntent, - const char* path, const struct lxc_rootfs *rootfs) + const char* path, const struct lxc_rootfs *rootfs, + const char *lxc_name, const char *lxc_path) { char *pathdirname = NULL; int ret = 0; FILE *pathfile = NULL; if (strncmp(mntent->mnt_type, "overlay", 7) == 0) { - if (mount_entry_create_overlay_dirs(mntent, rootfs) < 0) + if (mount_entry_create_overlay_dirs(mntent, rootfs, lxc_name, lxc_path) < 0) return -1; } else if (strncmp(mntent->mnt_type, "aufs", 4) == 0) { - if (mount_entry_create_aufs_dirs(mntent, rootfs) < 0) + if (mount_entry_create_aufs_dirs(mntent, rootfs, lxc_name, lxc_path) < 0) return -1; } @@ -1986,14 +1974,15 @@ static int mount_entry_create_dir_file(const struct mntent *mntent, } static inline int mount_entry_on_generic(struct mntent *mntent, - const char* path, const struct lxc_rootfs *rootfs) + const char* path, const struct lxc_rootfs *rootfs, + const char *lxc_name, const char *lxc_path) { unsigned long mntflags; char *mntdata; int ret; bool optional = hasmntopt(mntent, "optional") != NULL; - ret = mount_entry_create_dir_file(mntent, path, rootfs); + ret = mount_entry_create_dir_file(mntent, path, rootfs, lxc_name, lxc_path); if (ret < 0) return optional ? 0 : -1; @@ -2015,12 +2004,13 @@ static inline int mount_entry_on_generic(struct mntent *mntent, static inline int mount_entry_on_systemfs(struct mntent *mntent) { - return mount_entry_on_generic(mntent, mntent->mnt_dir, NULL); + return mount_entry_on_generic(mntent, mntent->mnt_dir, NULL, NULL, NULL); } static int mount_entry_on_absolute_rootfs(struct mntent *mntent, const struct lxc_rootfs *rootfs, - const char *lxc_name) + const char *lxc_name, + const char *lxc_path) { char *aux; char path[MAXPATHLEN]; @@ -2062,11 +2052,13 @@ skipabs: return -1; } - return mount_entry_on_generic(mntent, path, rootfs); + return mount_entry_on_generic(mntent, path, rootfs, lxc_name, lxc_path); } static int mount_entry_on_relative_rootfs(struct mntent *mntent, - const struct lxc_rootfs *rootfs) + const struct lxc_rootfs *rootfs, + const char *lxc_name, + const char *lxc_path) { char path[MAXPATHLEN]; int ret; @@ -2078,11 +2070,11 @@ static int mount_entry_on_relative_rootfs(struct mntent *mntent, return -1; } - return mount_entry_on_generic(mntent, path, rootfs); + return mount_entry_on_generic(mntent, path, rootfs, lxc_name, lxc_path); } static int mount_file_entries(const struct lxc_rootfs *rootfs, FILE *file, - const char *lxc_name) + const char *lxc_name, const char *lxc_path) { struct mntent mntent; char buf[4096]; @@ -2098,13 +2090,12 @@ static int mount_file_entries(const struct lxc_rootfs *rootfs, FILE *file, /* We have a separate root, mounts are relative to it */ if (mntent.mnt_dir[0] != '/') { - if (mount_entry_on_relative_rootfs(&mntent, - rootfs)) + if (mount_entry_on_relative_rootfs(&mntent, rootfs, lxc_name, lxc_path)) goto out; continue; } - if (mount_entry_on_absolute_rootfs(&mntent, rootfs, lxc_name)) + if (mount_entry_on_absolute_rootfs(&mntent, rootfs, lxc_name, lxc_path)) goto out; } @@ -2116,7 +2107,7 @@ out: } static int setup_mount(const struct lxc_rootfs *rootfs, const char *fstab, - const char *lxc_name) + const char *lxc_name, const char *lxc_path) { FILE *file; int ret; @@ -2130,7 +2121,7 @@ static int setup_mount(const struct lxc_rootfs *rootfs, const char *fstab, return -1; } - ret = mount_file_entries(rootfs, file, lxc_name); + ret = mount_file_entries(rootfs, file, lxc_name, lxc_path); endmntent(file); return ret; @@ -2158,7 +2149,7 @@ FILE *write_mount_file(struct lxc_list *mount) } static int setup_mount_entries(const struct lxc_rootfs *rootfs, struct lxc_list *mount, - const char *lxc_name) + const char *lxc_name, const char *lxc_path) { FILE *file; int ret; @@ -2167,7 +2158,7 @@ static int setup_mount_entries(const struct lxc_rootfs *rootfs, struct lxc_list if (!file) return -1; - ret = mount_file_entries(rootfs, file, lxc_name); + ret = mount_file_entries(rootfs, file, lxc_name, lxc_path); fclose(file); return ret; @@ -3891,12 +3882,12 @@ int lxc_setup(struct lxc_handler *handler) return -1; } - if (setup_mount(&lxc_conf->rootfs, lxc_conf->fstab, name)) { + if (setup_mount(&lxc_conf->rootfs, lxc_conf->fstab, name, lxcpath)) { ERROR("failed to setup the mounts for '%s'", name); return -1; } - if (!lxc_list_empty(&lxc_conf->mount_list) && setup_mount_entries(&lxc_conf->rootfs, &lxc_conf->mount_list, name)) { + if (!lxc_list_empty(&lxc_conf->mount_list) && setup_mount_entries(&lxc_conf->rootfs, &lxc_conf->mount_list, name, lxcpath)) { ERROR("failed to setup the mount entries for '%s'", name); return -1; } -- 2.6.1 _______________________________________________ lxc-devel mailing list lxc-devel@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-devel