Re: [PATCH net-next v4 07/13] octeontx2-af: npc: cn20k: Prepare for new SoC

Simon Horman
2026-01-22T08:36:14Z

On Tue, Jan 13, 2026 at 03:46:52PM +0530, Ratheesh Kannoth wrote:

...

> diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_npc_fs.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_npc_fs.c
> index 508233876fc1..d73e447bedca 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_npc_fs.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_npc_fs.c
> @@ -903,11 +903,12 @@ static int npc_check_unsupported_flows(struct rvu *rvu, u64 features, u8 intf)
> * dont care.
> */
> void npc_update_entry(struct rvu *rvu, enum key_fields type,
> - struct mcam_entry *entry, u64 val_lo,
> + struct mcam_entry_mdata *mdata, u64 val_lo,
> u64 val_hi, u64 mask_lo, u64 mask_hi, u8 intf)
> {
> struct npc_mcam *mcam = &rvu->hw->mcam;
> struct mcam_entry dummy = { {0} };
> + u64 *kw, *kw_mask, *val, *mask;
> struct npc_key_field *field;
> u64 kw1, kw2, kw3;
> int i, max_kw;
> @@ -920,10 +921,9 @@ void npc_update_entry(struct rvu *rvu, enum key_fields type,
> if (!field->nr_kws)
> return;
>
> - if (is_cn20k(rvu->pdev))
> - max_kw = NPC_MAX_KWS_IN_KEY;
> - else
> - max_kw = NPC_MAX_KWS_IN_KEY - 1;
> + max_kw = NPC_MAX_KWS_IN_KEY;
> + kw = dummy.kw;
> + kw_mask = dummy.kw_mask;
>
> for (i = 0; i < max_kw; i++) {
> if (!field->kw_mask[i])
> @@ -932,10 +932,10 @@ void npc_update_entry(struct rvu *rvu, enum key_fields type,
> shift = __ffs64(field->kw_mask[i]);
> /* update entry value */
> kw1 = (val_lo << shift) & field->kw_mask[i];
> - dummy.kw[i] = kw1;
> + kw[i] = kw1;
> /* update entry mask */
> kw1 = (mask_lo << shift) & field->kw_mask[i];
> - dummy.kw_mask[i] = kw1;
> + kw_mask[i] = kw1;
>
> if (field->nr_kws == 1)
> break;
> @@ -945,12 +945,12 @@ void npc_update_entry(struct rvu *rvu, enum key_fields type,
> kw2 = shift ? val_lo >> (64 - shift) : 0;
> kw2 |= (val_hi << shift);
> kw2 &= field->kw_mask[i + 1];
> - dummy.kw[i + 1] = kw2;
> + kw[i + 1] = kw2;

Hi Ratheesh,

It's not a problem introduced by this patch.
But it seems that this could overrun kw if i is max_kw - 1.
Likewise elsewhere in this loop.

Flagged by Smatch.

> /* update entry mask */
> kw2 = shift ? mask_lo >> (64 - shift) : 0;
> kw2 |= (mask_hi << shift);
> kw2 &= field->kw_mask[i + 1];
> - dummy.kw_mask[i + 1] = kw2;
> + kw_mask[i + 1] = kw2;
> break;
> }
> /* place remaining bits of key value in kw[x + 1], kw[x + 2] */
> @@ -961,34 +961,40 @@ void npc_update_entry(struct rvu *rvu, enum key_fields type,
> kw2 &= field->kw_mask[i + 1];
> kw3 = shift ? val_hi >> (64 - shift) : 0;
> kw3 &= field->kw_mask[i + 2];
> - dummy.kw[i + 1] = kw2;
> - dummy.kw[i + 2] = kw3;
> + kw[i + 1] = kw2;
> + kw[i + 2] = kw3;
> /* update entry mask */
> kw2 = shift ? mask_lo >> (64 - shift) : 0;
> kw2 |= (mask_hi << shift);
> kw2 &= field->kw_mask[i + 1];
> kw3 = shift ? mask_hi >> (64 - shift) : 0;
> kw3 &= field->kw_mask[i + 2];
> - dummy.kw_mask[i + 1] = kw2;
> - dummy.kw_mask[i + 2] = kw3;
> + kw_mask[i + 1] = kw2;
> + kw_mask[i + 2] = kw3;
> break;
> }
> }

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