| title: | Re RFC v14 rc2 PATCH 1 7 ipc allow alloc |
|
Quoting Oren Laadan (orenl@xxxxxxxxxxxxxxx):
Serge E. Hallyn wrote:
Quoting Oren Laadan (orenl@xxxxxxxxxxxxxxx):
-int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
+int
+ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int size, int req_id)
{
uid_t euid;
gid_t egid;
+ int lid = 0;
int id, err;
if (size IPCMNI)
@@ -268,28 +270,41 @@ int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
if (ids- in_use = size)
return -ENOSPC;
+ if (req_id = 0)
+ lid = ipcid_to_idx(req_id);
+
spin_lock_init(&new- lock);
new- deleted = 0;
rcu_read_lock();
spin_lock(&new- lock);
- err = idr_get_new(&ids- ipcs_idr, new, &id);
+ err = idr_get_new_above(&ids- ipcs_idr, new, lid, &id);
if (err) {
spin_unlock(&new- lock);
rcu_read_unlock();
return err;
}
+ if (req_id = 0) {
+ if (id != lid) {
+ idr_remove(&ids- ipcs_idr, id);
+ spin_unlock(&new- lock);
+ rcu_read_unlock();
+ return -EBUSY;
+ }
+ new- seq = req_id / SEQ_MULTIPLIER;
Should this be
new- seq = req_id % ids- seq_max;
?
This is how the user-visible IPC id is constructed:
static inline int ipc_buildid(int id, int seq)
{
return SEQ_MULTIPLIER * seq + id;
}
and I want to get the original seq .... (the id in this function is
an in-kernel identifier)
Hmm, yeah, I guess... I misunderstood what seq was doing. In
fact, now I just dont understand what its doing at all...
Weird.
+ } else {
+ new- seq = ids- seq++;
+ if (ids- seq ids- seq_max)
+ ids- seq = 0;
+ }
+
ids- in_use++;
current_euid_egid(&euid, &egid);
new- cuid = new- uid = euid;
new- gid = new- cgid = egid;
- new- seq = ids- seq++;
- if(ids- seq ids- seq_max)
- ids- seq = 0;
-
_______________________________________________
Containers mailing list
Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx
rel="nofollow" lists.linux-foundation.org/mailman/listinfo/containers lists.linux-foundation.org/mailman/listinfo/containers
|
