Re: [PATCH] ipc: WARN if trying to remove ipc object which is absent

[Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>]

Hi,

On 11/29/21 20:48, Alexander Mikhalitsyn wrote:
> For 4.14.y:
>
> Upstream commit 126e8bee943e ("ipc: WARN if trying to remove ipc object which is absent")
>
> Patch series "shm: shm_rmid_forced feature fixes".
[...]
> ---
>   ipc/util.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/ipc/util.c b/ipc/util.c
> index 5a65b0cbae7d..198b4c1c3ad3 100644
> --- a/ipc/util.c
> +++ b/ipc/util.c
> @@ -409,8 +409,8 @@ static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
>   static void ipc_kht_remove(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
>   {
>   	if (ipcp->key != IPC_PRIVATE)
> -		rhashtable_remove_fast(&ids->key_ht, &ipcp->khtnode,
> -				       ipc_kht_params);
> +		WARN_ON_ONCE(rhashtable_remove_fast(&ids->key_ht, &ipcp->khtnode,
> +				       ipc_kht_params));
>   }
>   
>   /**
> @@ -425,7 +425,7 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
>   {
>   	int lid = ipcid_to_idx(ipcp->id);
>   
> -	idr_remove(&ids->ipcs_idr, lid);
> +	WARN_ON_ONCE(idr_remove(&ids->ipcs_idr, lid) != ipcp);
>   	ipc_kht_remove(ids, ipcp);
>   	ids->in_use--;
>   	ipcp->deleted = true;

Tested: With the patch applied, the warning is printed.


--

    manfred