diff mbox series

[RFC,15/35] libsepol: reject invalid default targets

Message ID 20211011162533.53404-16-cgzones@googlemail.com (mailing list archive)
State Changes Requested
Headers show
Series libsepol: add fuzzer for reading binary policies | expand

Commit Message

Christian Göttsche Oct. 11, 2021, 4:25 p.m. UTC 
Reject loading a policy with invalid default targets so that all
following code, e.g. the different output modes, do not need to handle
unsupported ones.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
---
 libsepol/src/policydb.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

Comments

James Carter Oct. 18, 2021, 7:58 p.m. UTC | #1 
On Mon, Oct 11, 2021 at 12:41 PM Christian Göttsche
<cgzones@googlemail.com> wrote:
>
> Reject loading a policy with invalid default targets so that all
> following code, e.g. the different output modes, do not need to handle
> unsupported ones.
>
> Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
> ---
>  libsepol/src/policydb.c | 37 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
>
> diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c
> index 980af059..5e8b4a3f 100644
> --- a/libsepol/src/policydb.c
> +++ b/libsepol/src/policydb.c
> @@ -2313,8 +2313,37 @@ static int class_read(policydb_t * p, hashtab_t h, struct policy_file *fp)
>                 if (rc < 0)
>                         goto bad;
>                 cladatum->default_user = le32_to_cpu(buf[0]);
> +               switch (cladatum->default_user) {
> +               case 0:
> +               case DEFAULT_SOURCE:
> +               case DEFAULT_TARGET:
> +                       break;
> +               default:
> +                       goto bad;
> +               }
>                 cladatum->default_role = le32_to_cpu(buf[1]);
> +               switch (cladatum->default_role) {
> +               case 0:
> +               case DEFAULT_SOURCE:
> +               case DEFAULT_TARGET:
> +                       break;
> +               default:
> +                       goto bad;
> +               }
>                 cladatum->default_range = le32_to_cpu(buf[2]);
> +               switch (cladatum->default_range) {
> +               case 0:
> +               case DEFAULT_SOURCE_LOW:
> +               case DEFAULT_SOURCE_HIGH:
> +               case DEFAULT_SOURCE_LOW_HIGH:
> +               case DEFAULT_TARGET_LOW:
> +               case DEFAULT_TARGET_HIGH:
> +               case DEFAULT_TARGET_LOW_HIGH:
> +               case DEFAULT_GLBLUB:
> +                       break;
> +               default:
> +                       goto bad;
> +               }
>         }
>
>         if ((p->policy_type == POLICY_KERN &&
> @@ -2325,6 +2354,14 @@ static int class_read(policydb_t * p, hashtab_t h, struct policy_file *fp)
>                 if (rc < 0)
>                         goto bad;
>                 cladatum->default_type = le32_to_cpu(buf[0]);
> +               switch (cladatum->default_type) {
> +               case 0:
> +               case DEFAULT_SOURCE:
> +               case DEFAULT_TARGET:
> +                       break;
> +               default:
> +                       goto bad;
> +               }
>         }
>
>         if (hashtab_insert(h, key, cladatum))
> --
> 2.33.0
>

Same comment as for patch 14, I would like to see this in
policydb_validate.c and checked when validating the policydb.

Thanks,
Jim
diff mbox series

Patch

diff --git a/libsepol/src/policydb.c b/libsepol/src/policydb.c
index 980af059..5e8b4a3f 100644
--- a/libsepol/src/policydb.c
+++ b/libsepol/src/policydb.c
@@ -2313,8 +2313,37 @@  static int class_read(policydb_t * p, hashtab_t h, struct policy_file *fp)
 		if (rc < 0)
 			goto bad;
 		cladatum->default_user = le32_to_cpu(buf[0]);
+		switch (cladatum->default_user) {
+		case 0:
+		case DEFAULT_SOURCE:
+		case DEFAULT_TARGET:
+			break;
+		default:
+			goto bad;
+		}
 		cladatum->default_role = le32_to_cpu(buf[1]);
+		switch (cladatum->default_role) {
+		case 0:
+		case DEFAULT_SOURCE:
+		case DEFAULT_TARGET:
+			break;
+		default:
+			goto bad;
+		}
 		cladatum->default_range = le32_to_cpu(buf[2]);
+		switch (cladatum->default_range) {
+		case 0:
+		case DEFAULT_SOURCE_LOW:
+		case DEFAULT_SOURCE_HIGH:
+		case DEFAULT_SOURCE_LOW_HIGH:
+		case DEFAULT_TARGET_LOW:
+		case DEFAULT_TARGET_HIGH:
+		case DEFAULT_TARGET_LOW_HIGH:
+		case DEFAULT_GLBLUB:
+			break;
+		default:
+			goto bad;
+		}
 	}
 
 	if ((p->policy_type == POLICY_KERN &&
@@ -2325,6 +2354,14 @@  static int class_read(policydb_t * p, hashtab_t h, struct policy_file *fp)
 		if (rc < 0)
 			goto bad;
 		cladatum->default_type = le32_to_cpu(buf[0]);
+		switch (cladatum->default_type) {
+		case 0:
+		case DEFAULT_SOURCE:
+		case DEFAULT_TARGET:
+			break;
+		default:
+			goto bad;
+		}
 	}
 
 	if (hashtab_insert(h, key, cladatum))