From: Harini Katakam harini.katakam@xilinx.com
[ Upstream commit 85520079afce885b80647fbd0d13d8f03d057167 ]
macb_ptp_desc will not return NULL under most circumstances with correct Kconfig and IP design config register. But for the sake of the extreme corner case, check for NULL when using the helper. In case of rx_tstamp, no action is necessary except to return (similar to timestamp disabled) and warn. In case of TX, return -EINVAL to let the skb be free. Perform this check before marking skb in progress. Fixes coverity warning: (4) Event dereference: Dereferencing a null pointer "desc_ptp"
Signed-off-by: Harini Katakam harini.katakam@xilinx.com Reviewed-by: Radhey Shyam Pandey radhey.shyam.pandey@xilinx.com Signed-off-by: Michal Simek michal.simek@xilinx.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/cadence/macb_ptp.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c index 43a3f0dbf857..f5aec28c7730 100644 --- a/drivers/net/ethernet/cadence/macb_ptp.c +++ b/drivers/net/ethernet/cadence/macb_ptp.c @@ -275,6 +275,12 @@ void gem_ptp_rxstamp(struct macb *bp, struct sk_buff *skb,
if (GEM_BFEXT(DMA_RXVALID, desc->addr)) { desc_ptp = macb_ptp_desc(bp, desc); + /* Unlikely but check */ + if (!desc_ptp) { + dev_warn_ratelimited(&bp->pdev->dev, + "Timestamp not supported in BD\n"); + return; + } gem_hw_timestamp(bp, desc_ptp->ts_1, desc_ptp->ts_2, &ts); memset(shhwtstamps, 0, sizeof(struct skb_shared_hwtstamps)); shhwtstamps->hwtstamp = ktime_set(ts.tv_sec, ts.tv_nsec); @@ -307,8 +313,11 @@ int gem_ptp_txstamp(struct macb_queue *queue, struct sk_buff *skb, if (CIRC_SPACE(head, tail, PTP_TS_BUFFER_SIZE) == 0) return -ENOMEM;
- skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; desc_ptp = macb_ptp_desc(queue->bp, desc); + /* Unlikely but check */ + if (!desc_ptp) + return -EINVAL; + skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; tx_timestamp = &queue->tx_timestamps[head]; tx_timestamp->skb = skb; /* ensure ts_1/ts_2 is loaded after ctrl (TX_USED check) */