| Message ID | 20250224111251.1061098-2-wei.fang@nxp.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: enetc: fix some known issues | expand |
On Mon, Feb 24, 2025 at 07:12:44PM +0800, Wei Fang wrote: > When a DMA mapping error occurs while processing skb frags, it will free > one more tx_swbd than expected, so fix this off-by-one issue. > > Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet drivers") > Cc: stable@vger.kernel.org > Suggested-by: Vladimir Oltean <vladimir.oltean@nxp.com> > Suggested-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> > Signed-off-by: Wei Fang <wei.fang@nxp.com> > --- Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> -----Original Message----- > From: Wei Fang <wei.fang@nxp.com> > Sent: Monday, February 24, 2025 1:13 PM [...] > Subject: [PATCH v3 net 1/8] net: enetc: fix the off-by-one issue in > enetc_map_tx_buffs() > > When a DMA mapping error occurs while processing skb frags, it will free > one more tx_swbd than expected, so fix this off-by-one issue. > > Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet > drivers") > Cc: stable@vger.kernel.org > Suggested-by: Vladimir Oltean <vladimir.oltean@nxp.com> > Suggested-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> > Signed-off-by: Wei Fang <wei.fang@nxp.com> > --- Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>
diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 6a6fc819dfde..55ad31a5073e 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -167,6 +167,24 @@ static bool enetc_skb_is_tcp(struct sk_buff *skb) return skb->csum_offset == offsetof(struct tcphdr, check); } +/** + * enetc_unwind_tx_frame() - Unwind the DMA mappings of a multi-buffer Tx frame + * @tx_ring: Pointer to the Tx ring on which the buffer descriptors are located + * @count: Number of Tx buffer descriptors which need to be unmapped + * @i: Index of the last successfully mapped Tx buffer descriptor + */ +static void enetc_unwind_tx_frame(struct enetc_bdr *tx_ring, int count, int i) +{ + while (count--) { + struct enetc_tx_swbd *tx_swbd = &tx_ring->tx_swbd[i]; + + enetc_free_tx_frame(tx_ring, tx_swbd); + if (i == 0) + i = tx_ring->bd_count; + i--; + } +} + static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb) { bool do_vlan, do_onestep_tstamp = false, do_twostep_tstamp = false; @@ -372,13 +390,7 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb) dma_err: dev_err(tx_ring->dev, "DMA map error"); - do { - tx_swbd = &tx_ring->tx_swbd[i]; - enetc_free_tx_frame(tx_ring, tx_swbd); - if (i == 0) - i = tx_ring->bd_count; - i--; - } while (count--); + enetc_unwind_tx_frame(tx_ring, count, i); return 0; }
When a DMA mapping error occurs while processing skb frags, it will free one more tx_swbd than expected, so fix this off-by-one issue. Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet drivers") Cc: stable@vger.kernel.org Suggested-by: Vladimir Oltean <vladimir.oltean@nxp.com> Suggested-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Signed-off-by: Wei Fang <wei.fang@nxp.com> --- drivers/net/ethernet/freescale/enetc/enetc.c | 26 ++++++++++++++------ 1 file changed, 19 insertions(+), 7 deletions(-)