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>
This commit is contained in:
Kohei Kaigai 2011-04-01 15:39:26 +01:00 committed by Eric Paris
parent 6bde95ce33
commit f50a3ec961
3 changed files with 26 additions and 13 deletions

View file

@ -112,8 +112,8 @@ void security_compute_av_user(u32 ssid, u32 tsid,
int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
const struct qstr *qstr, u32 *out_sid);
int security_transition_sid_user(u32 ssid, u32 tsid,
u16 tclass, u32 *out_sid);
int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
const char *objname, u32 *out_sid);
int security_member_sid(u32 ssid, u32 tsid,
u16 tclass, u32 *out_sid);

View file

@ -753,11 +753,13 @@ out:
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 @@ static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
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 @@ static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
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 @@ static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
length = len;
out:
kfree(newcon);
kfree(namebuf);
kfree(tcon);
kfree(scon);
return length;

View file

@ -1360,14 +1360,14 @@ out:
static void filename_compute_type(struct policydb *p, struct context *newcontext,
u32 scon, u32 tcon, u16 tclass,
const struct qstr *qstr)
const char *objname)
{
struct filename_trans *ft;
for (ft = p->filename_trans; ft; ft = ft->next) {
if (ft->stype == scon &&
ft->ttype == tcon &&
ft->tclass == tclass &&
!strcmp(ft->name, qstr->name)) {
!strcmp(ft->name, objname)) {
newcontext->type = ft->otype;
return;
}
@ -1378,7 +1378,7 @@ static int security_compute_sid(u32 ssid,
u32 tsid,
u16 orig_tclass,
u32 specified,
const struct qstr *qstr,
const char *objname,
u32 *out_sid,
bool kern)
{
@ -1479,9 +1479,9 @@ static int security_compute_sid(u32 ssid,
}
/* if we have a qstr this is a file trans check so check those rules */
if (qstr)
if (objname)
filename_compute_type(&policydb, &newcontext, scontext->type,
tcontext->type, tclass, qstr);
tcontext->type, tclass, objname);
/* Check for class-specific changes. */
if (specified & AVTAB_TRANSITION) {
@ -1539,13 +1539,14 @@ int security_transition_sid(u32 ssid, u32 tsid, u16 tclass,
const struct qstr *qstr, u32 *out_sid)
{
return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
qstr, out_sid, true);
qstr ? qstr->name : NULL, out_sid, true);
}
int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass, u32 *out_sid)
int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass,
const char *objname, u32 *out_sid)
{
return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION,
NULL, out_sid, false);
objname, out_sid, false);
}
/**