From e34a98d5b226b84a3ed6da93e7a92e65cc1c81ba Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 17 Jan 2019 00:22:58 -0500 Subject: [PATCH] cgroup2: switch to option-by-option parsing [again, carved out of patch by dhowells] [NB: we probably want to handle "source" in parse_param here] Signed-off-by: Al Viro --- kernel/cgroup/cgroup.c | 62 ++++++++++++++++++++++-------------------- 1 file changed, 33 insertions(+), 29 deletions(-) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index faba00caa197..d0cddfbdf5cf 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -54,6 +54,7 @@ #include #include #include +#include #include #include #include @@ -1772,26 +1773,37 @@ int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node, return len; } -static int parse_cgroup_root_flags(char *data, unsigned int *root_flags) +enum cgroup2_param { + Opt_nsdelegate, + nr__cgroup2_params +}; + +static const struct fs_parameter_spec cgroup2_param_specs[] = { + fsparam_flag ("nsdelegate", Opt_nsdelegate), + {} +}; + +static const struct fs_parameter_description cgroup2_fs_parameters = { + .name = "cgroup2", + .specs = cgroup2_param_specs, +}; + +static int cgroup2_parse_param(struct fs_context *fc, struct fs_parameter *param) { - char *token; + struct cgroup_fs_context *ctx = cgroup_fc2context(fc); + struct fs_parse_result result; + int opt; - *root_flags = 0; + opt = fs_parse(fc, &cgroup2_fs_parameters, param, &result); + if (opt < 0) + return opt; - if (!data || *data == '\0') + switch (opt) { + case Opt_nsdelegate: + ctx->flags |= CGRP_ROOT_NS_DELEGATE; return 0; - - while ((token = strsep(&data, ",")) != NULL) { - if (!strcmp(token, "nsdelegate")) { - *root_flags |= CGRP_ROOT_NS_DELEGATE; - continue; - } - - pr_err("cgroup2: unknown option \"%s\"\n", token); - return -EINVAL; } - - return 0; + return -EINVAL; } static void apply_cgroup_root_flags(unsigned int root_flags) @@ -2074,15 +2086,6 @@ static void cgroup_fs_context_free(struct fs_context *fc) kfree(ctx); } -static int cgroup_parse_monolithic(struct fs_context *fc, void *data) -{ - struct cgroup_fs_context *ctx = cgroup_fc2context(fc); - - if (data) - security_sb_eat_lsm_opts(data, &fc->security); - return parse_cgroup_root_flags(data, &ctx->flags); -} - static int cgroup_get_tree(struct fs_context *fc) { struct cgroup_namespace *ns = current->nsproxy->cgroup_ns; @@ -2108,7 +2111,7 @@ static int cgroup_get_tree(struct fs_context *fc) static const struct fs_context_operations cgroup_fs_context_ops = { .free = cgroup_fs_context_free, - .parse_monolithic = cgroup_parse_monolithic, + .parse_param = cgroup2_parse_param, .get_tree = cgroup_get_tree, .reconfigure = cgroup_reconfigure, }; @@ -2174,10 +2177,11 @@ struct file_system_type cgroup_fs_type = { }; static struct file_system_type cgroup2_fs_type = { - .name = "cgroup2", - .init_fs_context = cgroup_init_fs_context, - .kill_sb = cgroup_kill_sb, - .fs_flags = FS_USERNS_MOUNT, + .name = "cgroup2", + .init_fs_context = cgroup_init_fs_context, + .parameters = &cgroup2_fs_parameters, + .kill_sb = cgroup_kill_sb, + .fs_flags = FS_USERNS_MOUNT, }; int cgroup_path_ns_locked(struct cgroup *cgrp, char *buf, size_t buflen,