selinux: add type_transition with name extension support for selinuxfs
The attached patch allows /selinux/create takes optional 4th argument
to support TYPE_TRANSITION with name extension for userspace object
managers.
If 4th argument is not supplied, it shall perform as existing kernel.
In fact, the regression test of SE-PostgreSQL works well on the patched
kernel.
Thanks,
Signed-off-by: KaiGai Kohei <kohei.kaigai@eu.nec.com>
[manually verify fuzz was not an issue, and it wasn't: eparis]
Signed-off-by: Eric Paris <eparis@redhat.com>
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index ea39cb7..973f5a4 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -753,11 +753,13 @@
static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
+ char *namebuf = NULL, *objname = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
+ int nargs;
length = task_has_security(current, SECURITY__COMPUTE_CREATE);
if (length)
@@ -773,10 +775,18 @@
if (!tcon)
goto out;
- length = -EINVAL;
- if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
+ length = -ENOMEM;
+ namebuf = kzalloc(size + 1, GFP_KERNEL);
+ if (!namebuf)
goto out;
+ length = -EINVAL;
+ nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
+ if (nargs < 3 || nargs > 4)
+ goto out;
+ if (nargs == 4)
+ objname = namebuf;
+
length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
if (length)
goto out;
@@ -785,7 +795,8 @@
if (length)
goto out;
- length = security_transition_sid_user(ssid, tsid, tclass, &newsid);
+ length = security_transition_sid_user(ssid, tsid, tclass,
+ objname, &newsid);
if (length)
goto out;
@@ -804,6 +815,7 @@
length = len;
out:
kfree(newcon);
+ kfree(namebuf);
kfree(tcon);
kfree(scon);
return length;