SELinux: Socket retains creator role and MLS attribute

The socket SID would be computed on creation and no longer inherit
its creator's SID by default. Socket may have a different type but
needs to retain the creator's role and MLS attribute in order not
to break labeled networking and network access control.

The kernel value for a class would be used to determine if the class
if one of socket classes. If security_compute_sid is called from
userspace the policy value for a class would be mapped to the relevant
kernel value first.

Signed-off-by: Harry Ciao <qingtao.cao@windriver.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>

1 files changed, 3 insertions, 2 deletions

diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c
index 1ef8e4e89880..e96174216bc9 100644
--- a/security/selinux/ss/mls.c
+++ b/security/selinux/ss/mls.c
@@ -512,7 +512,8 @@ int mls_compute_sid(struct context *scontext,
                     struct context *tcontext,
                     u16 tclass,
                     u32 specified,
-                    struct context *newcontext)
+                    struct context *newcontext,
+                    bool sock)
 {
         struct range_trans rtr;
         struct mls_range *r;
@@ -531,7 +532,7 @@ int mls_compute_sid(struct context *scontext,
                         return mls_range_set(newcontext, r);
                 /* Fallthrough */
         case AVTAB_CHANGE:
-                if (tclass == policydb.process_class)
+                if ((tclass == policydb.process_class) || (sock == true))
                         /* Use the process MLS attributes. */
                         return mls_context_cpy(newcontext, scontext);
                 else