--- zzzz-none-000/linux-3.10.107/security/selinux/ss/ebitmap.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/security/selinux/ss/ebitmap.c	2021-02-04 17:41:59.000000000 +0000
@@ -86,51 +86,36 @@
  *
  */
 int ebitmap_netlbl_export(struct ebitmap *ebmap,
-			  struct netlbl_lsm_secattr_catmap **catmap)
+			  struct netlbl_lsm_catmap **catmap)
 {
 	struct ebitmap_node *e_iter = ebmap->node;
-	struct netlbl_lsm_secattr_catmap *c_iter;
-	u32 cmap_idx, cmap_sft;
-	int i;
-
-	/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
-	 * however, it is not always compatible with an array of unsigned long
-	 * in ebitmap_node.
-	 * In addition, you should pay attention the following implementation
-	 * assumes unsigned long has a width equal with or less than 64-bit.
-	 */
+	unsigned long e_map;
+	u32 offset;
+	unsigned int iter;
+	int rc;
 
 	if (e_iter == NULL) {
 		*catmap = NULL;
 		return 0;
 	}
 
-	c_iter = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
-	if (c_iter == NULL)
-		return -ENOMEM;
-	*catmap = c_iter;
-	c_iter->startbit = e_iter->startbit & ~(NETLBL_CATMAP_SIZE - 1);
+	if (*catmap != NULL)
+		netlbl_catmap_free(*catmap);
+	*catmap = NULL;
 
 	while (e_iter) {
-		for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
-			unsigned int delta, e_startbit, c_endbit;
-
-			e_startbit = e_iter->startbit + i * EBITMAP_UNIT_SIZE;
-			c_endbit = c_iter->startbit + NETLBL_CATMAP_SIZE;
-			if (e_startbit >= c_endbit) {
-				c_iter->next
-				  = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
-				if (c_iter->next == NULL)
+		offset = e_iter->startbit;
+		for (iter = 0; iter < EBITMAP_UNIT_NUMS; iter++) {
+			e_map = e_iter->maps[iter];
+			if (e_map != 0) {
+				rc = netlbl_catmap_setlong(catmap,
+							   offset,
+							   e_map,
+							   GFP_ATOMIC);
+				if (rc != 0)
 					goto netlbl_export_failure;
-				c_iter = c_iter->next;
-				c_iter->startbit
-				  = e_startbit & ~(NETLBL_CATMAP_SIZE - 1);
 			}
-			delta = e_startbit - c_iter->startbit;
-			cmap_idx = delta / NETLBL_CATMAP_MAPSIZE;
-			cmap_sft = delta % NETLBL_CATMAP_MAPSIZE;
-			c_iter->bitmap[cmap_idx]
-				|= e_iter->maps[i] << cmap_sft;
+			offset += EBITMAP_UNIT_SIZE;
 		}
 		e_iter = e_iter->next;
 	}
@@ -138,7 +123,7 @@
 	return 0;
 
 netlbl_export_failure:
-	netlbl_secattr_catmap_free(*catmap);
+	netlbl_catmap_free(*catmap);
 	return -ENOMEM;
 }
 
@@ -153,58 +138,50 @@
  *
  */
 int ebitmap_netlbl_import(struct ebitmap *ebmap,
-			  struct netlbl_lsm_secattr_catmap *catmap)
+			  struct netlbl_lsm_catmap *catmap)
 {
+	int rc;
 	struct ebitmap_node *e_iter = NULL;
-	struct ebitmap_node *emap_prev = NULL;
-	struct netlbl_lsm_secattr_catmap *c_iter = catmap;
-	u32 c_idx, c_pos, e_idx, e_sft;
-
-	/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
-	 * however, it is not always compatible with an array of unsigned long
-	 * in ebitmap_node.
-	 * In addition, you should pay attention the following implementation
-	 * assumes unsigned long has a width equal with or less than 64-bit.
-	 */
-
-	do {
-		for (c_idx = 0; c_idx < NETLBL_CATMAP_MAPCNT; c_idx++) {
-			unsigned int delta;
-			u64 map = c_iter->bitmap[c_idx];
-
-			if (!map)
-				continue;
-
-			c_pos = c_iter->startbit
-				+ c_idx * NETLBL_CATMAP_MAPSIZE;
-			if (!e_iter
-			    || c_pos >= e_iter->startbit + EBITMAP_SIZE) {
-				e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
-				if (!e_iter)
-					goto netlbl_import_failure;
-				e_iter->startbit
-					= c_pos - (c_pos % EBITMAP_SIZE);
-				if (emap_prev == NULL)
-					ebmap->node = e_iter;
-				else
-					emap_prev->next = e_iter;
-				emap_prev = e_iter;
-			}
-			delta = c_pos - e_iter->startbit;
-			e_idx = delta / EBITMAP_UNIT_SIZE;
-			e_sft = delta % EBITMAP_UNIT_SIZE;
-			while (map) {
-				e_iter->maps[e_idx++] |= map & (-1UL);
-				map = EBITMAP_SHIFT_UNIT_SIZE(map);
-			}
+	struct ebitmap_node *e_prev = NULL;
+	u32 offset = 0, idx;
+	unsigned long bitmap;
+
+	for (;;) {
+		rc = netlbl_catmap_getlong(catmap, &offset, &bitmap);
+		if (rc < 0)
+			goto netlbl_import_failure;
+		if (offset == (u32)-1)
+			return 0;
+
+		/* don't waste ebitmap space if the netlabel bitmap is empty */
+		if (bitmap == 0) {
+			offset += EBITMAP_UNIT_SIZE;
+			continue;
+		}
+
+		if (e_iter == NULL ||
+		    offset >= e_iter->startbit + EBITMAP_SIZE) {
+			e_prev = e_iter;
+			e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
+			if (e_iter == NULL)
+				goto netlbl_import_failure;
+			e_iter->startbit = offset & ~(EBITMAP_SIZE - 1);
+			if (e_prev == NULL)
+				ebmap->node = e_iter;
+			else
+				e_prev->next = e_iter;
+			ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
 		}
-		c_iter = c_iter->next;
-	} while (c_iter);
-	if (e_iter != NULL)
-		ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
-	else
-		ebitmap_destroy(ebmap);
 
+		/* offset will always be aligned to an unsigned long */
+		idx = EBITMAP_NODE_INDEX(e_iter, offset);
+		e_iter->maps[idx] = bitmap;
+
+		/* next */
+		offset += EBITMAP_UNIT_SIZE;
+	}
+
+	/* NOTE: we should never reach this return */
 	return 0;
 
 netlbl_import_failure:
@@ -213,7 +190,12 @@
 }
 #endif /* CONFIG_NETLABEL */
 
-int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2)
+/*
+ * Check to see if all the bits set in e2 are also set in e1. Optionally,
+ * if last_e2bit is non-zero, the highest set bit in e2 cannot exceed
+ * last_e2bit.
+ */
+int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2, u32 last_e2bit)
 {
 	struct ebitmap_node *n1, *n2;
 	int i;
@@ -223,14 +205,25 @@
 
 	n1 = e1->node;
 	n2 = e2->node;
+
 	while (n1 && n2 && (n1->startbit <= n2->startbit)) {
 		if (n1->startbit < n2->startbit) {
 			n1 = n1->next;
 			continue;
 		}
-		for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
+		for (i = EBITMAP_UNIT_NUMS - 1; (i >= 0) && !n2->maps[i]; )
+			i--;	/* Skip trailing NULL map entries */
+		if (last_e2bit && (i >= 0)) {
+			u32 lastsetbit = n2->startbit + i * EBITMAP_UNIT_SIZE +
+					 __fls(n2->maps[i]);
+			if (lastsetbit > last_e2bit)
+				return 0;
+		}
+
+		while (i >= 0) {
 			if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
 				return 0;
+			i--;
 		}
 
 		n1 = n1->next;