Use a wrapper to guard `malloc(a * b)` type allocations, to detect
multiplication overflows, which result in too few memory being
allocated.
Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
---
libsepol/src/conditional.c | 2 +-
libsepol/src/expand.c | 4 ++--
libsepol/src/hashtab.c | 4 +++-
libsepol/src/link.c | 3 ++-
libsepol/src/module.c | 4 ++--
libsepol/src/module_to_cil.c | 4 ++--
libsepol/src/optimize.c | 6 ++++--
libsepol/src/policydb.c | 6 +++---
libsepol/src/private.h | 9 +++++++++
libsepol/src/services.c | 6 +++---
libsepol/src/sidtab.c | 3 ++-
libsepol/src/user_record.c | 3 ++-
libsepol/src/write.c | 2 +-
13 files changed, 36 insertions(+), 20 deletions(-)
diff --git a/libsepol/src/conditional.c b/libsepol/src/conditional.c
index 1edac65d..cc3f4d82 100644
--- a/libsepol/src/conditional.c
+++ b/libsepol/src/conditional.c
@@ -522,7 +522,7 @@ int cond_init_bool_indexes(policydb_t * p)
if (p->bool_val_to_struct)
free(p->bool_val_to_struct);
p->bool_val_to_struct = (cond_bool_datum_t **)
- malloc(p->p_bools.nprim * sizeof(cond_bool_datum_t *));
+ mallocarray(p->p_bools.nprim, sizeof(cond_bool_datum_t *));
if (!p->bool_val_to_struct)
return -1;
return 0;
diff --git a/libsepol/src/expand.c b/libsepol/src/expand.c
index a6a466f7..8a7259a0 100644
--- a/libsepol/src/expand.c
+++ b/libsepol/src/expand.c
@@ -3146,9 +3146,9 @@ int expand_module(sepol_handle_t * handle,
goto cleanup;
/* Build the type<->attribute maps and remove attributes. */
- state.out->attr_type_map = malloc(state.out->p_types.nprim *
+ state.out->attr_type_map = mallocarray(state.out->p_types.nprim,
sizeof(ebitmap_t));
- state.out->type_attr_map = malloc(state.out->p_types.nprim *
+ state.out->type_attr_map = mallocarray(state.out->p_types.nprim,
sizeof(ebitmap_t));
if (!state.out->attr_type_map || !state.out->type_attr_map) {
ERR(handle, "Out of memory!");
diff --git a/libsepol/src/hashtab.c b/libsepol/src/hashtab.c
index 21143b76..2eb35212 100644
--- a/libsepol/src/hashtab.c
+++ b/libsepol/src/hashtab.c
@@ -32,6 +32,8 @@
#include <string.h>
#include <sepol/policydb/hashtab.h>
+#include "private.h"
+
hashtab_t hashtab_create(unsigned int (*hash_value) (hashtab_t h,
const_hashtab_key_t key),
int (*keycmp) (hashtab_t h,
@@ -52,7 +54,7 @@ hashtab_t hashtab_create(unsigned int (*hash_value) (hashtab_t h,
p->nel = 0;
p->hash_value = hash_value;
p->keycmp = keycmp;
- p->htable = (hashtab_ptr_t *) malloc(sizeof(hashtab_ptr_t) * size);
+ p->htable = (hashtab_ptr_t *) mallocarray(size, sizeof(hashtab_ptr_t));
if (p->htable == NULL) {
free(p);
return NULL;
diff --git a/libsepol/src/link.c b/libsepol/src/link.c
index 7512a4d9..bd986b7b 100644
--- a/libsepol/src/link.c
+++ b/libsepol/src/link.c
@@ -34,6 +34,7 @@
#include <assert.h>
#include "debug.h"
+#include "private.h"
#undef min
#define min(a,b) (((a) < (b)) ? (a) : (b))
@@ -1679,7 +1680,7 @@ static int copy_scope_index(scope_index_t * src, scope_index_t * dest,
}
/* next copy the enabled permissions data */
- if ((dest->class_perms_map = malloc(largest_mapped_class_value *
+ if ((dest->class_perms_map = mallocarray(largest_mapped_class_value,
sizeof(*dest->class_perms_map))) ==
NULL) {
goto cleanup;
diff --git a/libsepol/src/module.c b/libsepol/src/module.c
index 02a5de2c..4a51f25c 100644
--- a/libsepol/src/module.c
+++ b/libsepol/src/module.c
@@ -406,14 +406,14 @@ static int module_package_read_offsets(sepol_module_package_t * mod,
goto err;
}
- off = (size_t *) malloc((nsec + 1) * sizeof(size_t));
+ off = (size_t *) mallocarray(nsec + 1, sizeof(size_t));
if (!off) {
ERR(file->handle, "out of memory");
goto err;
}
free(buf);
- buf = malloc(sizeof(uint32_t) * nsec);
+ buf = mallocarray(nsec, sizeof(uint32_t));
if (!buf) {
ERR(file->handle, "out of memory");
goto err;
diff --git a/libsepol/src/module_to_cil.c b/libsepol/src/module_to_cil.c
index 16e4004e..ad0880bd 100644
--- a/libsepol/src/module_to_cil.c
+++ b/libsepol/src/module_to_cil.c
@@ -430,7 +430,7 @@ static int stack_init(struct stack **stack)
goto exit;
}
- s->stack = malloc(sizeof(*s->stack) * STACK_SIZE);
+ s->stack = mallocarray(STACK_SIZE, sizeof(*s->stack));
if (s->stack == NULL) {
goto exit;
}
@@ -1008,7 +1008,7 @@ static int ebitmap_to_names(struct ebitmap *map, char **vals_to_names, char ***n
goto exit;
}
- name_arr = malloc(sizeof(*name_arr) * num);
+ name_arr = mallocarray(num, sizeof(*name_arr));
if (name_arr == NULL) {
log_err("Out of memory");
rc = -1;
diff --git a/libsepol/src/optimize.c b/libsepol/src/optimize.c
index 6826155c..f8298fb7 100644
--- a/libsepol/src/optimize.c
+++ b/libsepol/src/optimize.c
@@ -31,6 +31,8 @@
#include <sepol/policydb/policydb.h>
#include <sepol/policydb/conditional.h>
+#include "private.h"
+
#define TYPE_VEC_INIT_SIZE 16
struct type_vec {
@@ -42,7 +44,7 @@ static int type_vec_init(struct type_vec *v)
{
v->capacity = TYPE_VEC_INIT_SIZE;
v->count = 0;
- v->types = malloc(v->capacity * sizeof(*v->types));
+ v->types = mallocarray(v->capacity, sizeof(*v->types));
if (!v->types)
return -1;
return 0;
@@ -93,7 +95,7 @@ static struct type_vec *build_type_map(const policydb_t *p)
{
unsigned int i, k;
ebitmap_node_t *n;
- struct type_vec *map = malloc(p->p_types.nprim * sizeof(*map));
+ struct type_vec *map = mallocarray(p->p_types.nprim, sizeof(*map));
if (!map)
return NULL;
diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c
index 587ba64a..dcea1807 100644
--- a/libsepol/src/policydb.c
+++ b/libsepol/src/policydb.c
@@ -4111,7 +4111,7 @@ static int scope_read(policydb_t * p, int symnum, struct policy_file *fp)
goto cleanup;
}
if ((scope->decl_ids =
- malloc(scope->decl_ids_len * sizeof(uint32_t))) == NULL) {
+ mallocarray(scope->decl_ids_len, sizeof(uint32_t))) == NULL) {
goto cleanup;
}
rc = next_entry(scope->decl_ids, fp, sizeof(uint32_t) * scope->decl_ids_len);
@@ -4500,8 +4500,8 @@ int policydb_read(policydb_t * p, struct policy_file *fp, unsigned verbose)
}
if (policy_type == POLICY_KERN) {
- p->type_attr_map = malloc(p->p_types.nprim * sizeof(ebitmap_t));
- p->attr_type_map = malloc(p->p_types.nprim * sizeof(ebitmap_t));
+ p->type_attr_map = mallocarray(p->p_types.nprim, sizeof(ebitmap_t));
+ p->attr_type_map = mallocarray(p->p_types.nprim, sizeof(ebitmap_t));
if (!p->type_attr_map || !p->attr_type_map)
goto bad;
for (i = 0; i < p->p_types.nprim; i++) {
diff --git a/libsepol/src/private.h b/libsepol/src/private.h
index 6146f59f..d3d65a57 100644
--- a/libsepol/src/private.h
+++ b/libsepol/src/private.h
@@ -83,3 +83,12 @@ extern int next_entry(void *buf, struct policy_file *fp, size_t bytes);
extern size_t put_entry(const void *ptr, size_t size, size_t n,
struct policy_file *fp);
extern int str_read(char **strp, struct policy_file *fp, size_t len);
+
+static inline void* mallocarray(size_t nmemb, size_t size) {
+ if (size && nmemb > (size_t)-1 / size) {
+ errno = ENOMEM;
+ return NULL;
+ }
+
+ return malloc(nmemb * size);
+}
diff --git a/libsepol/src/services.c b/libsepol/src/services.c
index 3407058f..edcdde21 100644
--- a/libsepol/src/services.c
+++ b/libsepol/src/services.c
@@ -712,7 +712,7 @@ mls_ops:
* Generate the same number of answer buffer entries as expression
* buffers (as there will never be more).
*/
- answer_list = malloc(expr_count * sizeof(*answer_list));
+ answer_list = mallocarray(expr_count, sizeof(*answer_list));
if (!answer_list) {
ERR(NULL, "failed to allocate answer stack");
rc = -ENOMEM;
@@ -2163,7 +2163,7 @@ int sepol_get_user_sids(sepol_security_id_t fromsid,
}
usercon.user = user->s.value;
- mysids = malloc(maxnel * sizeof(sepol_security_id_t));
+ mysids = mallocarray(maxnel, sizeof(sepol_security_id_t));
if (!mysids) {
rc = -ENOMEM;
goto out;
@@ -2199,7 +2199,7 @@ int sepol_get_user_sids(sepol_security_id_t fromsid,
} else {
maxnel += SIDS_NEL;
mysids2 =
- malloc(maxnel *
+ mallocarray(maxnel,
sizeof(sepol_security_id_t));
if (!mysids2) {
diff --git a/libsepol/src/sidtab.c b/libsepol/src/sidtab.c
index 255e0725..adeae6eb 100644
--- a/libsepol/src/sidtab.c
+++ b/libsepol/src/sidtab.c
@@ -15,6 +15,7 @@
#include <sepol/policydb/sidtab.h>
#include "flask.h"
+#include "private.h"
#define SIDTAB_HASH(sid) \
(sid & SIDTAB_HASH_MASK)
@@ -27,7 +28,7 @@ int sepol_sidtab_init(sidtab_t * s)
{
int i;
- s->htable = malloc(sizeof(sidtab_ptr_t) * SIDTAB_SIZE);
+ s->htable = mallocarray(SIDTAB_SIZE, sizeof(sidtab_ptr_t));
if (!s->htable)
return -ENOMEM;
for (i = 0; i < SIDTAB_SIZE; i++)
diff --git a/libsepol/src/user_record.c b/libsepol/src/user_record.c
index ac520060..c1356a6b 100644
--- a/libsepol/src/user_record.c
+++ b/libsepol/src/user_record.c
@@ -4,6 +4,7 @@
#include "user_internal.h"
#include "debug.h"
+#include "private.h"
struct sepol_user {
/* This user's name */
@@ -265,7 +266,7 @@ int sepol_user_get_roles(sepol_handle_t * handle,
unsigned int i;
const char **tmp_roles =
- (const char **)malloc(sizeof(char *) * user->num_roles);
+ (const char **)mallocarray(user->num_roles, sizeof(char *));
if (!tmp_roles)
goto omem;
diff --git a/libsepol/src/write.c b/libsepol/src/write.c
index 3bd034d6..9df5b0bd 100644
--- a/libsepol/src/write.c
+++ b/libsepol/src/write.c
@@ -2117,7 +2117,7 @@ static int scope_write(hashtab_key_t key, hashtab_datum_t datum, void *ptr)
* buffer. this would have been easier with C99's
* dynamic arrays... */
rc = POLICYDB_ERROR;
- dyn_buf = malloc(items * sizeof(*dyn_buf));
+ dyn_buf = mallocarray(items, sizeof(*dyn_buf));
if (!dyn_buf)
goto err;
buf = dyn_buf;
--
2.33.1
