On 03/16/2019 02:52 PM, Manfred Spraul wrote:
> Hi,
>
> On 2/28/19 7:47 PM, Waiman Long wrote:
>> @@ -216,10 +221,11 @@ static inline int ipc_idr_alloc(struct ipc_ids
>> *ids, struct kern_ipc_perm *new)
>> */
>> if (next_id < 0) { /* !CHECKPOINT_RESTORE or next_id is unset */
>> - new->seq = ids->seq++;
>> - if (ids->seq > IPCID_SEQ_MAX)
>> - ids->seq = 0;
>> idx = idr_alloc(&ids->ipcs_idr, new, 0, 0, GFP_NOWAIT);
>> + if ((idx <= ids->last_idx) && (++ids->seq > IPCID_SEQ_MAX))
>> + ids->seq = 0;
>
> I'm always impressed by such lines:
>
> Everything in just two lines, use "++a", etc.
>
> But: How did you test it?
>
> idr_alloc() can fail, the code doesn't handle that :-(
>
>
You are right. I should have checked for the error case.
Thanks for spotting that.
Cheers,
Longman
