diff mbox

libsepol: Only apply bounds checking to source types in rules

Message ID 1461959620-26532-1-git-send-email-jwcart2@tycho.nsa.gov (mailing list archive)
State Not Applicable
Headers show

Commit Message

James Carter April 29, 2016, 7:53 p.m. UTC
The current bounds checking of both source and target types
requires allowing any domain that has access to the child domain
to also have the same permissions to the parent, which is undesirable.
Drop the target bounds expansion and checking.

Making this change fully functional requires a corresponding kernel
change; this change only allows one to build policies that would
otherwise violate the bounds checking on target type.  The kernel
change is required to allow the permissions at runtime.

Based on patch by Stephen Smalley.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
---
 libsepol/src/hierarchy.c | 37 -------------------------------------
 1 file changed, 37 deletions(-)

Comments

Stephen Smalley April 29, 2016, 8:06 p.m. UTC | #1
On 04/29/2016 03:53 PM, James Carter wrote:
> The current bounds checking of both source and target types
> requires allowing any domain that has access to the child domain
> to also have the same permissions to the parent, which is undesirable.
> Drop the target bounds expansion and checking.
> 
> Making this change fully functional requires a corresponding kernel
> change; this change only allows one to build policies that would
> otherwise violate the bounds checking on target type.  The kernel
> change is required to allow the permissions at runtime.
> 
> Based on patch by Stephen Smalley.
> 
> Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>

Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>

> ---
>  libsepol/src/hierarchy.c | 37 -------------------------------------
>  1 file changed, 37 deletions(-)
> 
> diff --git a/libsepol/src/hierarchy.c b/libsepol/src/hierarchy.c
> index 6f73195..b24b39e 100644
> --- a/libsepol/src/hierarchy.c
> +++ b/libsepol/src/hierarchy.c
> @@ -121,18 +121,6 @@ static int bounds_expand_rule(sepol_handle_t *handle, policydb_t *p,
>  		}
>  	}
>  
> -	if (ebitmap_get_bit(&p->attr_type_map[tgt - 1], parent - 1)) {
> -		avtab_key.target_type = parent;
> -		ebitmap_for_each_bit(&p->attr_type_map[src - 1], tnode, i) {
> -			if (!ebitmap_node_get_bit(tnode, i))
> -				continue;
> -			avtab_key.source_type = i + 1;
> -			rc = bounds_insert_rule(handle, avtab, global, other,
> -						&avtab_key, &datum);
> -			if (rc) goto exit;
> -		}
> -	}
> -
>  exit:
>  	return rc;
>  }
> @@ -329,31 +317,6 @@ static int bounds_check_rule(sepol_handle_t *handle, policydb_t *p,
>  			if (rc) goto exit;
>  		}
>  	}
> -	if (ebitmap_get_bit(&p->attr_type_map[tgt - 1], child - 1)) {
> -		avtab_key.target_type = parent;
> -		ebitmap_for_each_bit(&p->attr_type_map[src - 1], tnode, i) {
> -			if (!ebitmap_node_get_bit(tnode, i))
> -				continue;
> -			avtab_key.source_type = i + 1;
> -			if (avtab_key.source_type == child) {
> -				/* Checked above */
> -				continue;
> -			}
> -			d = bounds_not_covered(global_avtab, cur_avtab,
> -					       &avtab_key, data);
> -			if (!d) continue;
> -			td = p->type_val_to_struct[i];
> -			if (td && td->bounds) {
> -				avtab_key.source_type = td->bounds;
> -				d = bounds_not_covered(global_avtab, cur_avtab,
> -						       &avtab_key, data);
> -				if (!d) continue;
> -			}
> -			(*numbad)++;
> -			rc = bounds_add_bad(handle, i+1, child, class, d, bad);
> -			if (rc) goto exit;
> -		}
> -	}
>  
>  exit:
>  	return rc;
>
James Carter April 29, 2016, 8:08 p.m. UTC | #2
On 04/29/2016 04:06 PM, Stephen Smalley wrote:
> On 04/29/2016 03:53 PM, James Carter wrote:
>> The current bounds checking of both source and target types
>> requires allowing any domain that has access to the child domain
>> to also have the same permissions to the parent, which is undesirable.
>> Drop the target bounds expansion and checking.
>>
>> Making this change fully functional requires a corresponding kernel
>> change; this change only allows one to build policies that would
>> otherwise violate the bounds checking on target type.  The kernel
>> change is required to allow the permissions at runtime.
>>
>> Based on patch by Stephen Smalley.
>>
>> Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
>
> Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
>

Applied.

Jim

>> ---
>>   libsepol/src/hierarchy.c | 37 -------------------------------------
>>   1 file changed, 37 deletions(-)
>>
>> diff --git a/libsepol/src/hierarchy.c b/libsepol/src/hierarchy.c
>> index 6f73195..b24b39e 100644
>> --- a/libsepol/src/hierarchy.c
>> +++ b/libsepol/src/hierarchy.c
>> @@ -121,18 +121,6 @@ static int bounds_expand_rule(sepol_handle_t *handle, policydb_t *p,
>>   		}
>>   	}
>>
>> -	if (ebitmap_get_bit(&p->attr_type_map[tgt - 1], parent - 1)) {
>> -		avtab_key.target_type = parent;
>> -		ebitmap_for_each_bit(&p->attr_type_map[src - 1], tnode, i) {
>> -			if (!ebitmap_node_get_bit(tnode, i))
>> -				continue;
>> -			avtab_key.source_type = i + 1;
>> -			rc = bounds_insert_rule(handle, avtab, global, other,
>> -						&avtab_key, &datum);
>> -			if (rc) goto exit;
>> -		}
>> -	}
>> -
>>   exit:
>>   	return rc;
>>   }
>> @@ -329,31 +317,6 @@ static int bounds_check_rule(sepol_handle_t *handle, policydb_t *p,
>>   			if (rc) goto exit;
>>   		}
>>   	}
>> -	if (ebitmap_get_bit(&p->attr_type_map[tgt - 1], child - 1)) {
>> -		avtab_key.target_type = parent;
>> -		ebitmap_for_each_bit(&p->attr_type_map[src - 1], tnode, i) {
>> -			if (!ebitmap_node_get_bit(tnode, i))
>> -				continue;
>> -			avtab_key.source_type = i + 1;
>> -			if (avtab_key.source_type == child) {
>> -				/* Checked above */
>> -				continue;
>> -			}
>> -			d = bounds_not_covered(global_avtab, cur_avtab,
>> -					       &avtab_key, data);
>> -			if (!d) continue;
>> -			td = p->type_val_to_struct[i];
>> -			if (td && td->bounds) {
>> -				avtab_key.source_type = td->bounds;
>> -				d = bounds_not_covered(global_avtab, cur_avtab,
>> -						       &avtab_key, data);
>> -				if (!d) continue;
>> -			}
>> -			(*numbad)++;
>> -			rc = bounds_add_bad(handle, i+1, child, class, d, bad);
>> -			if (rc) goto exit;
>> -		}
>> -	}
>>
>>   exit:
>>   	return rc;
>>
>
diff mbox

Patch

diff --git a/libsepol/src/hierarchy.c b/libsepol/src/hierarchy.c
index 6f73195..b24b39e 100644
--- a/libsepol/src/hierarchy.c
+++ b/libsepol/src/hierarchy.c
@@ -121,18 +121,6 @@  static int bounds_expand_rule(sepol_handle_t *handle, policydb_t *p,
 		}
 	}
 
-	if (ebitmap_get_bit(&p->attr_type_map[tgt - 1], parent - 1)) {
-		avtab_key.target_type = parent;
-		ebitmap_for_each_bit(&p->attr_type_map[src - 1], tnode, i) {
-			if (!ebitmap_node_get_bit(tnode, i))
-				continue;
-			avtab_key.source_type = i + 1;
-			rc = bounds_insert_rule(handle, avtab, global, other,
-						&avtab_key, &datum);
-			if (rc) goto exit;
-		}
-	}
-
 exit:
 	return rc;
 }
@@ -329,31 +317,6 @@  static int bounds_check_rule(sepol_handle_t *handle, policydb_t *p,
 			if (rc) goto exit;
 		}
 	}
-	if (ebitmap_get_bit(&p->attr_type_map[tgt - 1], child - 1)) {
-		avtab_key.target_type = parent;
-		ebitmap_for_each_bit(&p->attr_type_map[src - 1], tnode, i) {
-			if (!ebitmap_node_get_bit(tnode, i))
-				continue;
-			avtab_key.source_type = i + 1;
-			if (avtab_key.source_type == child) {
-				/* Checked above */
-				continue;
-			}
-			d = bounds_not_covered(global_avtab, cur_avtab,
-					       &avtab_key, data);
-			if (!d) continue;
-			td = p->type_val_to_struct[i];
-			if (td && td->bounds) {
-				avtab_key.source_type = td->bounds;
-				d = bounds_not_covered(global_avtab, cur_avtab,
-						       &avtab_key, data);
-				if (!d) continue;
-			}
-			(*numbad)++;
-			rc = bounds_add_bad(handle, i+1, child, class, d, bad);
-			if (rc) goto exit;
-		}
-	}
 
 exit:
 	return rc;