Re: [PATCH 4/6][RESEND] Emulex FC HBA driver: fix overflow of statically allocated array

[James Smart <James.Smart@Emulex.Com>]

NACK

The fix is contained in our 8.2.2 sources recently posted and pushed by James
as part of his last scsi fixes.

-- james s

Jesper Juhl wrote:
> (previously send on 09-Aug-2007 20:47)
> 
> Hi,
> 
> The Coverity checker noticed that we may overrun a statically allocated 
> array in drivers/scsi/lpfc/lpfc_sli.c::lpfc_sli_hbqbuf_find().
> 
> The case is this; In 'struct lpfc_hba' we have 
> 
> 	#define LPFC_MAX_HBQS  4
> 	...
> 	struct lpfc_hba {
> 		...
> 		struct hbq_s hbqs[LPFC_MAX_HBQS];
> 		...
> 	};
> 
> But then in lpfc_sli_hbqbuf_find() we have this code 
> 
> 	hbqno = tag >> 16;
> 	if (hbqno > LPFC_MAX_HBQS)
> 		return NULL;
> 
> if 'hbqno' ends up as exactely 4, then we won't return, and then this
> 
> 	list_for_each_entry(d_buf, &phba->hbqs[hbqno].hbq_buffer_list, list) {
> 
> will cause an overflow of the statically allocated array at index 4, 
> since the valid indices are only 0-3. 
> 
> I propose this patch, that simply changes the 'hbqno > LPFC_MAX_HBQS' 
> into 'hbqno >= LPFC_MAX_HBQS' as a possible fix.
> 
> 
> Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
> Acked-by: James Smart <james.smart@emulex.com>
> ---
> 
>  drivers/scsi/lpfc/lpfc_sli.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
> index ce5ff2b..e5337ad 100644
> --- a/drivers/scsi/lpfc/lpfc_sli.c
> +++ b/drivers/scsi/lpfc/lpfc_sli.c
> @@ -675,7 +675,7 @@ lpfc_sli_hbqbuf_find(struct lpfc_hba *phba, uint32_t tag)
>  	uint32_t hbqno;
>  
>  	hbqno = tag >> 16;
> -	if (hbqno > LPFC_MAX_HBQS)
> +	if (hbqno >= LPFC_MAX_HBQS)
>  		return NULL;
>  
>  	list_for_each_entry(d_buf, &phba->hbqs[hbqno].hbq_buffer_list, list) {
> 
> 
> 
>