[PATCH] update of IPC audit record cleanup

The following patch addresses most of the issues with the IPC_SET_PERM
records as described in:
https://www.redhat.com/archives/linux-audit/2006-May/msg00010.html
and addresses the comments I received on the record field names.

To summarize, I made the following changes:

1. Changed sys_msgctl() and semctl_down() so that an IPC_SET_PERM
   record is emitted in the failure case as well as the success case.
   This matches the behavior in sys_shmctl().  I could simplify the
   code in sys_msgctl() and semctl_down() slightly but it would mean
   that in some error cases we could get an IPC_SET_PERM record
   without an IPC record and that seemed odd.

2. No change to the IPC record type, given no feedback on the backward
   compatibility question.

3. Removed the qbytes field from the IPC record.  It wasn't being
   set and when audit_ipc_obj() is called from ipcperms(), the
   information isn't available.  If we want the information in the IPC
   record, more extensive changes will be necessary.  Since it only
   applies to message queues and it isn't really permission related, it
   doesn't seem worth it.

4. Removed the obj field from the IPC_SET_PERM record.  This means that
   the kern_ipc_perm argument is no longer needed.

5. Removed the spaces and renamed the IPC_SET_PERM field names.  Replaced iuid and
   igid fields with ouid and ogid in the IPC record.

I tested this with the lspp.22 kernel on an x86_64 box.  I believe it
applies cleanly on the latest kernel.

-- ljk

Signed-off-by: Linda Knippers <linda.knippers@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 11 insertions, 8 deletions

diff --git a/ipc/msg.c b/ipc/msg.c
index 7d1340ccb16b..00f015a092d2 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -454,6 +454,11 @@ asmlinkage long sys_msgctl (int msqid, int cmd, struct msqid_ds __user *buf)
         err = audit_ipc_obj(ipcp);
         if (err)
                 goto out_unlock_up;
+        if (cmd==IPC_SET) {
+                err = audit_ipc_set_perm(setbuf.qbytes, setbuf.uid, setbuf.gid, setbuf.mode);
+                if (err)
+                        goto out_unlock_up;
+        }
 
         err = -EPERM;
         if (current->euid != ipcp->cuid && 
@@ -468,10 +473,6 @@ asmlinkage long sys_msgctl (int msqid, int cmd, struct msqid_ds __user *buf)
         switch (cmd) {
         case IPC_SET:
         {
-                err = audit_ipc_set_perm(setbuf.qbytes, setbuf.uid, setbuf.gid, setbuf.mode, ipcp);
-                if (err)
-                        goto out_unlock_up;
-
                 err = -EPERM;
                 if (setbuf.qbytes > msg_ctlmnb && !capable(CAP_SYS_RESOURCE))
                         goto out_unlock_up;
diff --git a/ipc/sem.c b/ipc/sem.c
index 7919f8ece6ba..fce0bc8b5ad6 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -828,6 +828,11 @@ static int semctl_down(int semid, int semnum, int cmd, int version, union semun
         if (err)
                 goto out_unlock;
 
+        if (cmd == IPC_SET) {
+                err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode);
+                if (err)
+                        goto out_unlock;
+        }
         if (current->euid != ipcp->cuid && 
             current->euid != ipcp->uid && !capable(CAP_SYS_ADMIN)) {
                 err=-EPERM;
@@ -844,9 +849,6 @@ static int semctl_down(int semid, int semnum, int cmd, int version, union semun
                 err = 0;
                 break;
         case IPC_SET:
-                err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode, ipcp);
-                if (err)
-                        goto out_unlock;
                 ipcp->uid = setbuf.uid;
                 ipcp->gid = setbuf.gid;
                 ipcp->mode = (ipcp->mode & ~S_IRWXUGO)
diff --git a/ipc/shm.c b/ipc/shm.c
index 809896851902..4f133d24030f 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -643,7 +643,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
                 err = audit_ipc_obj(&(shp->shm_perm));
                 if (err)
                         goto out_unlock_up;
-                err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode, &(shp->shm_perm));
+                err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode);
                 if (err)
                         goto out_unlock_up;
                 err=-EPERM;