| Message ID | 20200116120439.303034-5-omosnace@redhat.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | selinux: Assorted simplifications and cleanups | expand |
On 1/16/20 7:04 AM, Ondrej Mosnacek wrote: > Since it is fixed-size after allocation and we know the size beforehand, > using a plain old array is simpler and more efficient. > > Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> > --- > security/selinux/ss/conditional.c | 125 ++++++++++++------------------ > security/selinux/ss/conditional.h | 8 +- > 2 files changed, 53 insertions(+), 80 deletions(-) > > diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c > index c8a02c9b23ee..b847fd2a6a51 100644 > --- a/security/selinux/ss/conditional.c > +++ b/security/selinux/ss/conditional.c > @@ -87,8 +87,9 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr) > */ > void evaluate_cond_node(struct policydb *p, struct cond_node *node) > { > + struct avtab_node *avnode; > int new_state; > - struct cond_av_list *cur; > + u32 i; > > new_state = cond_evaluate_expr(p, node->expr); > if (new_state != node->cur_state) { > @@ -96,19 +97,21 @@ void evaluate_cond_node(struct policydb *p, struct cond_node *node) > if (new_state == -1) > pr_err("SELinux: expression result was undefined - disabling all rules.\n"); > /* turn the rules on or off */ > - for (cur = node->true_list; cur; cur = cur->next) { > + for (i = 0; i < node->true_list.len; i++) { > + avnode = node->true_list.nodes[i]; > if (new_state <= 0) > - cur->node->key.specified &= ~AVTAB_ENABLED; > + avnode->key.specified &= ~AVTAB_ENABLED; > else > - cur->node->key.specified |= AVTAB_ENABLED; > + avnode->key.specified |= AVTAB_ENABLED; > } > > - for (cur = node->false_list; cur; cur = cur->next) { > + for (i = 0; i < node->false_list.len; i++) { > + avnode = node->false_list.nodes[i]; > /* -1 or 1 */ > if (new_state) > - cur->node->key.specified &= ~AVTAB_ENABLED; > + avnode->key.specified &= ~AVTAB_ENABLED; > else > - cur->node->key.specified |= AVTAB_ENABLED; > + avnode->key.specified |= AVTAB_ENABLED; > } > } > } > @@ -128,16 +131,6 @@ int cond_policydb_init(struct policydb *p) > return 0; > } > > -static void cond_av_list_destroy(struct cond_av_list *list) > -{ > - struct cond_av_list *cur, *next; > - for (cur = list; cur; cur = next) { > - next = cur->next; > - /* the avtab_ptr_t node is destroy by the avtab */ > - kfree(cur); > - } > -} > - > static void cond_node_destroy(struct cond_node *node) > { > struct cond_expr *cur_expr, *next_expr; > @@ -146,8 +139,9 @@ static void cond_node_destroy(struct cond_node *node) > next_expr = cur_expr->next; > kfree(cur_expr); > } > - cond_av_list_destroy(node->true_list); > - cond_av_list_destroy(node->false_list); > + /* the avtab_ptr_t nodes are destroyed by the avtab */ > + kfree(node->true_list.nodes); > + kfree(node->false_list.nodes); > } > > static void cond_list_destroy(struct policydb *p) > @@ -255,19 +249,17 @@ err: > > struct cond_insertf_data { > struct policydb *p; > + struct avtab_node **dst; > struct cond_av_list *other; > - struct cond_av_list *head; > - struct cond_av_list *tail; > }; > > static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr) > { > struct cond_insertf_data *data = ptr; > struct policydb *p = data->p; > - struct cond_av_list *other = data->other, *list, *cur; > struct avtab_node *node_ptr; > - u8 found; > - int rc = -EINVAL; > + u32 i; > + bool found; > > /* > * For type rules we have to make certain there aren't any > @@ -277,7 +269,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum > if (k->specified & AVTAB_TYPE) { > if (avtab_search(&p->te_avtab, k)) { > pr_err("SELinux: type rule already exists outside of a conditional.\n"); > - goto err; > + return -EINVAL; > } > /* > * If we are reading the false list other will be a pointer to > @@ -287,29 +279,29 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum > * If we are reading the true list (other == NULL) there shouldn't > * be any other entries. > */ > - if (other) { > + if (data->other) { > node_ptr = avtab_search_node(&p->te_cond_avtab, k); > if (node_ptr) { > if (avtab_search_node_next(node_ptr, k->specified)) { > pr_err("SELinux: too many conflicting type rules.\n"); > - goto err; > + return -EINVAL; > } > - found = 0; > - for (cur = other; cur; cur = cur->next) { > - if (cur->node == node_ptr) { > - found = 1; > + found = false; > + for (i = 0; i < data->other->len; i++) { > + if (data->other->nodes[i] == node_ptr) { > + found = true; > break; > } > } > if (!found) { > pr_err("SELinux: conflicting type rules.\n"); > - goto err; > + return -EINVAL; > } > } > } else { > if (avtab_search(&p->te_cond_avtab, k)) { > pr_err("SELinux: conflicting type rules when adding type rule for true.\n"); > - goto err; > + return -EINVAL; > } > } > } > @@ -317,39 +309,22 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum > node_ptr = avtab_insert_nonunique(&p->te_cond_avtab, k, d); > if (!node_ptr) { > pr_err("SELinux: could not insert rule.\n"); > - rc = -ENOMEM; > - goto err; > - } > - > - list = kzalloc(sizeof(*list), GFP_KERNEL); > - if (!list) { > - rc = -ENOMEM; > - goto err; > + return -ENOMEM; > } > > - list->node = node_ptr; > - if (!data->head) > - data->head = list; > - else > - data->tail->next = list; > - data->tail = list; > + *data->dst = node_ptr; > return 0; > - > -err: > - cond_av_list_destroy(data->head); > - data->head = NULL; > - return rc; > } > > -static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list **ret_list, struct cond_av_list *other) > +static int cond_read_av_list(struct policydb *p, void *fp, > + struct cond_av_list *list, > + struct cond_av_list *other) > { > - int i, rc; > + int rc; > __le32 buf[1]; > - u32 len; > + u32 i, len; > struct cond_insertf_data data; > > - *ret_list = NULL; > - > rc = next_entry(buf, fp, sizeof(u32)); > if (rc) > return rc; > @@ -358,18 +333,24 @@ static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list * > if (len == 0) > return 0; > > + list->nodes = kcalloc(len, sizeof(*list->nodes), GFP_KERNEL); > + if (!list->nodes) > + return -ENOMEM; > + > data.p = p; > data.other = other; > - data.head = NULL; > - data.tail = NULL; > for (i = 0; i < len; i++) { > + data.dst = &list->nodes[i]; > rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf, > &data); > - if (rc) > + if (rc) { > + kfree(list->nodes); > + list->nodes = NULL; > return rc; > + } > } > > - *ret_list = data.head; > + list->len = len; > return 0; > } > > @@ -432,7 +413,7 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) > rc = cond_read_av_list(p, fp, &node->true_list, NULL); > if (rc) > goto err; > - rc = cond_read_av_list(p, fp, &node->false_list, node->true_list); > + rc = cond_read_av_list(p, fp, &node->false_list, &node->true_list); > if (rc) > goto err; > return 0; > @@ -511,24 +492,16 @@ static int cond_write_av_list(struct policydb *p, > struct cond_av_list *list, struct policy_file *fp) > { > __le32 buf[1]; > - struct cond_av_list *cur_list; > - u32 len; > + u32 i; > int rc; > > - len = 0; > - for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) > - len++; > - > - buf[0] = cpu_to_le32(len); > + buf[0] = cpu_to_le32(list->len); > rc = put_entry(buf, sizeof(u32), 1, fp); > if (rc) > return rc; > > - if (len == 0) > - return 0; > - > - for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) { > - rc = avtab_write_item(p, cur_list->node, fp); > + for (i = 0; i < list->len; i++) { > + rc = avtab_write_item(p, list->nodes[i], fp); > if (rc) > return rc; > } > @@ -565,10 +538,10 @@ static int cond_write_node(struct policydb *p, struct cond_node *node, > return rc; > } > > - rc = cond_write_av_list(p, node->true_list, fp); > + rc = cond_write_av_list(p, &node->true_list, fp); > if (rc) > return rc; > - rc = cond_write_av_list(p, node->false_list, fp); > + rc = cond_write_av_list(p, &node->false_list, fp); > if (rc) > return rc; > > diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h > index e474bdd3a0ed..5f97f678440e 100644 > --- a/security/selinux/ss/conditional.h > +++ b/security/selinux/ss/conditional.h > @@ -39,8 +39,8 @@ struct cond_expr { > * struct is for that list. > */ > struct cond_av_list { > - struct avtab_node *node; > - struct cond_av_list *next; > + struct avtab_node **nodes; > + u32 len; > }; > > /* > @@ -53,8 +53,8 @@ struct cond_av_list { > struct cond_node { > int cur_state; > struct cond_expr *expr; > - struct cond_av_list *true_list; > - struct cond_av_list *false_list; > + struct cond_av_list true_list; > + struct cond_av_list false_list; > }; > > int cond_policydb_init(struct policydb *p); >
diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index c8a02c9b23ee..b847fd2a6a51 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -87,8 +87,9 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr) */ void evaluate_cond_node(struct policydb *p, struct cond_node *node) { + struct avtab_node *avnode; int new_state; - struct cond_av_list *cur; + u32 i; new_state = cond_evaluate_expr(p, node->expr); if (new_state != node->cur_state) { @@ -96,19 +97,21 @@ void evaluate_cond_node(struct policydb *p, struct cond_node *node) if (new_state == -1) pr_err("SELinux: expression result was undefined - disabling all rules.\n"); /* turn the rules on or off */ - for (cur = node->true_list; cur; cur = cur->next) { + for (i = 0; i < node->true_list.len; i++) { + avnode = node->true_list.nodes[i]; if (new_state <= 0) - cur->node->key.specified &= ~AVTAB_ENABLED; + avnode->key.specified &= ~AVTAB_ENABLED; else - cur->node->key.specified |= AVTAB_ENABLED; + avnode->key.specified |= AVTAB_ENABLED; } - for (cur = node->false_list; cur; cur = cur->next) { + for (i = 0; i < node->false_list.len; i++) { + avnode = node->false_list.nodes[i]; /* -1 or 1 */ if (new_state) - cur->node->key.specified &= ~AVTAB_ENABLED; + avnode->key.specified &= ~AVTAB_ENABLED; else - cur->node->key.specified |= AVTAB_ENABLED; + avnode->key.specified |= AVTAB_ENABLED; } } } @@ -128,16 +131,6 @@ int cond_policydb_init(struct policydb *p) return 0; } -static void cond_av_list_destroy(struct cond_av_list *list) -{ - struct cond_av_list *cur, *next; - for (cur = list; cur; cur = next) { - next = cur->next; - /* the avtab_ptr_t node is destroy by the avtab */ - kfree(cur); - } -} - static void cond_node_destroy(struct cond_node *node) { struct cond_expr *cur_expr, *next_expr; @@ -146,8 +139,9 @@ static void cond_node_destroy(struct cond_node *node) next_expr = cur_expr->next; kfree(cur_expr); } - cond_av_list_destroy(node->true_list); - cond_av_list_destroy(node->false_list); + /* the avtab_ptr_t nodes are destroyed by the avtab */ + kfree(node->true_list.nodes); + kfree(node->false_list.nodes); } static void cond_list_destroy(struct policydb *p) @@ -255,19 +249,17 @@ err: struct cond_insertf_data { struct policydb *p; + struct avtab_node **dst; struct cond_av_list *other; - struct cond_av_list *head; - struct cond_av_list *tail; }; static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr) { struct cond_insertf_data *data = ptr; struct policydb *p = data->p; - struct cond_av_list *other = data->other, *list, *cur; struct avtab_node *node_ptr; - u8 found; - int rc = -EINVAL; + u32 i; + bool found; /* * For type rules we have to make certain there aren't any @@ -277,7 +269,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum if (k->specified & AVTAB_TYPE) { if (avtab_search(&p->te_avtab, k)) { pr_err("SELinux: type rule already exists outside of a conditional.\n"); - goto err; + return -EINVAL; } /* * If we are reading the false list other will be a pointer to @@ -287,29 +279,29 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum * If we are reading the true list (other == NULL) there shouldn't * be any other entries. */ - if (other) { + if (data->other) { node_ptr = avtab_search_node(&p->te_cond_avtab, k); if (node_ptr) { if (avtab_search_node_next(node_ptr, k->specified)) { pr_err("SELinux: too many conflicting type rules.\n"); - goto err; + return -EINVAL; } - found = 0; - for (cur = other; cur; cur = cur->next) { - if (cur->node == node_ptr) { - found = 1; + found = false; + for (i = 0; i < data->other->len; i++) { + if (data->other->nodes[i] == node_ptr) { + found = true; break; } } if (!found) { pr_err("SELinux: conflicting type rules.\n"); - goto err; + return -EINVAL; } } } else { if (avtab_search(&p->te_cond_avtab, k)) { pr_err("SELinux: conflicting type rules when adding type rule for true.\n"); - goto err; + return -EINVAL; } } } @@ -317,39 +309,22 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum node_ptr = avtab_insert_nonunique(&p->te_cond_avtab, k, d); if (!node_ptr) { pr_err("SELinux: could not insert rule.\n"); - rc = -ENOMEM; - goto err; - } - - list = kzalloc(sizeof(*list), GFP_KERNEL); - if (!list) { - rc = -ENOMEM; - goto err; + return -ENOMEM; } - list->node = node_ptr; - if (!data->head) - data->head = list; - else - data->tail->next = list; - data->tail = list; + *data->dst = node_ptr; return 0; - -err: - cond_av_list_destroy(data->head); - data->head = NULL; - return rc; } -static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list **ret_list, struct cond_av_list *other) +static int cond_read_av_list(struct policydb *p, void *fp, + struct cond_av_list *list, + struct cond_av_list *other) { - int i, rc; + int rc; __le32 buf[1]; - u32 len; + u32 i, len; struct cond_insertf_data data; - *ret_list = NULL; - rc = next_entry(buf, fp, sizeof(u32)); if (rc) return rc; @@ -358,18 +333,24 @@ static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list * if (len == 0) return 0; + list->nodes = kcalloc(len, sizeof(*list->nodes), GFP_KERNEL); + if (!list->nodes) + return -ENOMEM; + data.p = p; data.other = other; - data.head = NULL; - data.tail = NULL; for (i = 0; i < len; i++) { + data.dst = &list->nodes[i]; rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf, &data); - if (rc) + if (rc) { + kfree(list->nodes); + list->nodes = NULL; return rc; + } } - *ret_list = data.head; + list->len = len; return 0; } @@ -432,7 +413,7 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp) rc = cond_read_av_list(p, fp, &node->true_list, NULL); if (rc) goto err; - rc = cond_read_av_list(p, fp, &node->false_list, node->true_list); + rc = cond_read_av_list(p, fp, &node->false_list, &node->true_list); if (rc) goto err; return 0; @@ -511,24 +492,16 @@ static int cond_write_av_list(struct policydb *p, struct cond_av_list *list, struct policy_file *fp) { __le32 buf[1]; - struct cond_av_list *cur_list; - u32 len; + u32 i; int rc; - len = 0; - for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) - len++; - - buf[0] = cpu_to_le32(len); + buf[0] = cpu_to_le32(list->len); rc = put_entry(buf, sizeof(u32), 1, fp); if (rc) return rc; - if (len == 0) - return 0; - - for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) { - rc = avtab_write_item(p, cur_list->node, fp); + for (i = 0; i < list->len; i++) { + rc = avtab_write_item(p, list->nodes[i], fp); if (rc) return rc; } @@ -565,10 +538,10 @@ static int cond_write_node(struct policydb *p, struct cond_node *node, return rc; } - rc = cond_write_av_list(p, node->true_list, fp); + rc = cond_write_av_list(p, &node->true_list, fp); if (rc) return rc; - rc = cond_write_av_list(p, node->false_list, fp); + rc = cond_write_av_list(p, &node->false_list, fp); if (rc) return rc; diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h index e474bdd3a0ed..5f97f678440e 100644 --- a/security/selinux/ss/conditional.h +++ b/security/selinux/ss/conditional.h @@ -39,8 +39,8 @@ struct cond_expr { * struct is for that list. */ struct cond_av_list { - struct avtab_node *node; - struct cond_av_list *next; + struct avtab_node **nodes; + u32 len; }; /* @@ -53,8 +53,8 @@ struct cond_av_list { struct cond_node { int cur_state; struct cond_expr *expr; - struct cond_av_list *true_list; - struct cond_av_list *false_list; + struct cond_av_list true_list; + struct cond_av_list false_list; }; int cond_policydb_init(struct policydb *p);
Since it is fixed-size after allocation and we know the size beforehand, using a plain old array is simpler and more efficient. Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> --- security/selinux/ss/conditional.c | 125 ++++++++++++------------------ security/selinux/ss/conditional.h | 8 +- 2 files changed, 53 insertions(+), 80 deletions(-)