ipcctl_pre_down_nolock (9) Linux Manual Page
ipcctl_pre_down_nolock – retrieve an ipc and check permissions for some IPC_XXX cmd
Synopsis
struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns, struct ipc_ids *ids, int id, int cmd, struct ipc64_perm *perm, int extra_perm);Arguments
ns
-
- ipc namespace
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 a pointer to the ipc object or otherwise, the corresponding error.
Call holding the both the rwsem and the rcu read lock.