ipcctl_pre_down(9)
NAME
ipcctl_pre_down - retrieve an ipc and check permissions for some
IPC_XXX cmd
SYNOPSIS
struct kern_ipc_perm * ipcctl_pre_down(struct ipc_ids * ids, int id,
int cmd,
struct ipc64_perm * perm,
int extra_perm);
ARGUMENTS
- ids
- the table of ids where to look for the ipc
- id
- the id of the ipc to retrieve
- cmd
- the cmd to check
- perm
- the permission to set
- extra_perm
- one extra permission parameter used by msq
DESCRIPTION
This function does some common audit and permissions check for some
IPC_XXX cmd and is called from semctl_down, shmctl_down and
msgctl_down. It must be called without any lock held and - retrieves
the ipc with the given id in the given table. - performs some audit and
permission check, depending on the given cmd - returns the ipc with
both ipc and rw_mutex locks held in case of success or an err-code
without any lock held otherwise.