selinux: convert to kvmalloc

The flex arrays were being used for constant sized arrays, so there's no
benefit to using flex_arrays over something simpler.

Link: http://lkml.kernel.org/r/20181217131929.11727-4-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index c1c31e3..6b576e5 100644
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -36,7 +36,6 @@
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/audit.h>
-#include <linux/flex_array.h>
 #include "security.h"
 
 #include "policydb.h"
@@ -341,17 +340,14 @@ static int common_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct common_datum *comdatum;
-	struct flex_array *fa;
 
 	comdatum = datum;
 	p = datap;
 	if (!comdatum->value || comdatum->value > p->p_commons.nprim)
 		return -EINVAL;
 
-	fa = p->sym_val_to_name[SYM_COMMONS];
-	if (flex_array_put_ptr(fa, comdatum->value - 1, key,
-			       GFP_KERNEL | __GFP_ZERO))
-		BUG();
+	p->sym_val_to_name[SYM_COMMONS][comdatum->value - 1] = key;
+
 	return 0;
 }
 
@@ -359,16 +355,13 @@ static int class_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct class_datum *cladatum;
-	struct flex_array *fa;
 
 	cladatum = datum;
 	p = datap;
 	if (!cladatum->value || cladatum->value > p->p_classes.nprim)
 		return -EINVAL;
-	fa = p->sym_val_to_name[SYM_CLASSES];
-	if (flex_array_put_ptr(fa, cladatum->value - 1, key,
-			       GFP_KERNEL | __GFP_ZERO))
-		BUG();
+
+	p->sym_val_to_name[SYM_CLASSES][cladatum->value - 1] = key;
 	p->class_val_to_struct[cladatum->value - 1] = cladatum;
 	return 0;
 }
@@ -377,7 +370,6 @@ static int role_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct role_datum *role;
-	struct flex_array *fa;
 
 	role = datum;
 	p = datap;
@@ -386,10 +378,7 @@ static int role_index(void *key, void *datum, void *datap)
 	    || role->bounds > p->p_roles.nprim)
 		return -EINVAL;
 
-	fa = p->sym_val_to_name[SYM_ROLES];
-	if (flex_array_put_ptr(fa, role->value - 1, key,
-			       GFP_KERNEL | __GFP_ZERO))
-		BUG();
+	p->sym_val_to_name[SYM_ROLES][role->value - 1] = key;
 	p->role_val_to_struct[role->value - 1] = role;
 	return 0;
 }
@@ -398,7 +387,6 @@ static int type_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct type_datum *typdatum;
-	struct flex_array *fa;
 
 	typdatum = datum;
 	p = datap;
@@ -408,15 +396,8 @@ static int type_index(void *key, void *datum, void *datap)
 		    || typdatum->value > p->p_types.nprim
 		    || typdatum->bounds > p->p_types.nprim)
 			return -EINVAL;
-		fa = p->sym_val_to_name[SYM_TYPES];
-		if (flex_array_put_ptr(fa, typdatum->value - 1, key,
-				       GFP_KERNEL | __GFP_ZERO))
-			BUG();
-
-		fa = p->type_val_to_struct_array;
-		if (flex_array_put_ptr(fa, typdatum->value - 1, typdatum,
-				       GFP_KERNEL | __GFP_ZERO))
-			BUG();
+		p->sym_val_to_name[SYM_TYPES][typdatum->value - 1] = key;
+		p->type_val_to_struct_array[typdatum->value - 1] = typdatum;
 	}
 
 	return 0;
@@ -426,7 +407,6 @@ static int user_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct user_datum *usrdatum;
-	struct flex_array *fa;
 
 	usrdatum = datum;
 	p = datap;
@@ -435,10 +415,7 @@ static int user_index(void *key, void *datum, void *datap)
 	    || usrdatum->bounds > p->p_users.nprim)
 		return -EINVAL;
 
-	fa = p->sym_val_to_name[SYM_USERS];
-	if (flex_array_put_ptr(fa, usrdatum->value - 1, key,
-			       GFP_KERNEL | __GFP_ZERO))
-		BUG();
+	p->sym_val_to_name[SYM_USERS][usrdatum->value - 1] = key;
 	p->user_val_to_struct[usrdatum->value - 1] = usrdatum;
 	return 0;
 }
@@ -447,7 +424,6 @@ static int sens_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct level_datum *levdatum;
-	struct flex_array *fa;
 
 	levdatum = datum;
 	p = datap;
@@ -456,10 +432,8 @@ static int sens_index(void *key, void *datum, void *datap)
 		if (!levdatum->level->sens ||
 		    levdatum->level->sens > p->p_levels.nprim)
 			return -EINVAL;
-		fa = p->sym_val_to_name[SYM_LEVELS];
-		if (flex_array_put_ptr(fa, levdatum->level->sens - 1, key,
-				       GFP_KERNEL | __GFP_ZERO))
-			BUG();
+
+		p->sym_val_to_name[SYM_LEVELS][levdatum->level->sens - 1] = key;
 	}
 
 	return 0;
@@ -469,7 +443,6 @@ static int cat_index(void *key, void *datum, void *datap)
 {
 	struct policydb *p;
 	struct cat_datum *catdatum;
-	struct flex_array *fa;
 
 	catdatum = datum;
 	p = datap;
@@ -477,10 +450,8 @@ static int cat_index(void *key, void *datum, void *datap)
 	if (!catdatum->isalias) {
 		if (!catdatum->value || catdatum->value > p->p_cats.nprim)
 			return -EINVAL;
-		fa = p->sym_val_to_name[SYM_CATS];
-		if (flex_array_put_ptr(fa, catdatum->value - 1, key,
-				       GFP_KERNEL | __GFP_ZERO))
-			BUG();
+
+		p->sym_val_to_name[SYM_CATS][catdatum->value - 1] = key;
 	}
 
 	return 0;
@@ -568,35 +539,23 @@ static int policydb_index(struct policydb *p)
 	if (!p->user_val_to_struct)
 		return -ENOMEM;
 
-	/* Yes, I want the sizeof the pointer, not the structure */
-	p->type_val_to_struct_array = flex_array_alloc(sizeof(struct type_datum *),
-						       p->p_types.nprim,
-						       GFP_KERNEL | __GFP_ZERO);
+	p->type_val_to_struct_array = kvcalloc(p->p_types.nprim,
+					       sizeof(*p->type_val_to_struct_array),
+					       GFP_KERNEL);
 	if (!p->type_val_to_struct_array)
 		return -ENOMEM;
 
-	rc = flex_array_prealloc(p->type_val_to_struct_array, 0,
-				 p->p_types.nprim, GFP_KERNEL | __GFP_ZERO);
-	if (rc)
-		goto out;
-
 	rc = cond_init_bool_indexes(p);
 	if (rc)
 		goto out;
 
 	for (i = 0; i < SYM_NUM; i++) {
-		p->sym_val_to_name[i] = flex_array_alloc(sizeof(char *),
-							 p->symtab[i].nprim,
-							 GFP_KERNEL | __GFP_ZERO);
+		p->sym_val_to_name[i] = kvcalloc(p->symtab[i].nprim,
+						 sizeof(char *),
+						 GFP_KERNEL);
 		if (!p->sym_val_to_name[i])
 			return -ENOMEM;
 
-		rc = flex_array_prealloc(p->sym_val_to_name[i],
-					 0, p->symtab[i].nprim,
-					 GFP_KERNEL | __GFP_ZERO);
-		if (rc)
-			goto out;
-
 		rc = hashtab_map(p->symtab[i].table, index_f[i], p);
 		if (rc)
 			goto out;
@@ -810,16 +769,13 @@ void policydb_destroy(struct policydb *p)
 		hashtab_destroy(p->symtab[i].table);
 	}
 
-	for (i = 0; i < SYM_NUM; i++) {
-		if (p->sym_val_to_name[i])
-			flex_array_free(p->sym_val_to_name[i]);
-	}
+	for (i = 0; i < SYM_NUM; i++)
+		kvfree(p->sym_val_to_name[i]);
 
 	kfree(p->class_val_to_struct);
 	kfree(p->role_val_to_struct);
 	kfree(p->user_val_to_struct);
-	if (p->type_val_to_struct_array)
-		flex_array_free(p->type_val_to_struct_array);
+	kvfree(p->type_val_to_struct_array);
 
 	avtab_destroy(&p->te_avtab);
 
@@ -872,17 +828,9 @@ void policydb_destroy(struct policydb *p)
 	hashtab_map(p->range_tr, range_tr_destroy, NULL);
 	hashtab_destroy(p->range_tr);
 
-	if (p->type_attr_map_array) {
-		for (i = 0; i < p->p_types.nprim; i++) {
-			struct ebitmap *e;
-
-			e = flex_array_get(p->type_attr_map_array, i);
-			if (!e)
-				continue;
-			ebitmap_destroy(e);
-		}
-		flex_array_free(p->type_attr_map_array);
-	}
+	for (i = 0; i < p->p_types.nprim; i++)
+		ebitmap_destroy(&p->type_attr_map_array[i]);
+	kvfree(p->type_attr_map_array);
 
 	ebitmap_destroy(&p->filename_trans_ttypes);
 	ebitmap_destroy(&p->policycaps);
@@ -1770,8 +1718,7 @@ static int type_bounds_sanity_check(void *key, void *datum, void *datap)
 			return -EINVAL;
 		}
 
-		upper = flex_array_get_ptr(p->type_val_to_struct_array,
-					   upper->bounds - 1);
+		upper = p->type_val_to_struct_array[upper->bounds - 1];
 		BUG_ON(!upper);
 
 		if (upper->attribute) {
@@ -2543,23 +2490,15 @@ int policydb_read(struct policydb *p, void *fp)
 	if (rc)
 		goto bad;
 
-	rc = -ENOMEM;
-	p->type_attr_map_array = flex_array_alloc(sizeof(struct ebitmap),
-						  p->p_types.nprim,
-						  GFP_KERNEL | __GFP_ZERO);
+	p->type_attr_map_array = kvcalloc(p->p_types.nprim,
+					  sizeof(*p->type_attr_map_array),
+					  GFP_KERNEL);
 	if (!p->type_attr_map_array)
 		goto bad;
 
-	/* preallocate so we don't have to worry about the put ever failing */
-	rc = flex_array_prealloc(p->type_attr_map_array, 0, p->p_types.nprim,
-				 GFP_KERNEL | __GFP_ZERO);
-	if (rc)
-		goto bad;
-
 	for (i = 0; i < p->p_types.nprim; i++) {
-		struct ebitmap *e = flex_array_get(p->type_attr_map_array, i);
+		struct ebitmap *e = &p->type_attr_map_array[i];
 
-		BUG_ON(!e);
 		ebitmap_init(e);
 		if (p->policyvers >= POLICYDB_VERSION_AVTAB) {
 			rc = ebitmap_read(e, fp);
@@ -3554,9 +3493,8 @@ int policydb_write(struct policydb *p, void *fp)
 		return rc;
 
 	for (i = 0; i < p->p_types.nprim; i++) {
-		struct ebitmap *e = flex_array_get(p->type_attr_map_array, i);
+		struct ebitmap *e = &p->type_attr_map_array[i];
 
-		BUG_ON(!e);
 		rc = ebitmap_write(e, fp);
 		if (rc)
 			return rc;