5.10-stable review patch. If anyone has any objections, please let me know.
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From: Ken Milmore ken.milmore@gmail.com
[ Upstream commit c71e3a5cffd5309d7f84444df03d5b72600cc417 ]
An issue was found on the RTL8125b when transmitting small fragmented packets, whereby invalid entries were inserted into the transmit ring buffer, subsequently leading to calls to dma_unmap_single() with a null address.
This was caused by rtl8169_start_xmit() not noticing changes to nr_frags which may occur when small packets are padded (to work around hardware quirks) in rtl8169_tso_csum_v2().
To fix this, postpone inspecting nr_frags until after any padding has been applied.
Fixes: 9020845fb5d6 ("r8169: improve rtl8169_start_xmit") Cc: stable@vger.kernel.org Signed-off-by: Ken Milmore ken.milmore@gmail.com Reviewed-by: Heiner Kallweit hkallweit1@gmail.com Link: https://lore.kernel.org/r/27ead18b-c23d-4f49-a020-1fc482c5ac95@gmail.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/realtek/r8169_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index dd4404efdb8d6..d24eb5ee152a5 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -4278,11 +4278,11 @@ static void rtl8169_doorbell(struct rtl8169_private *tp) static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, struct net_device *dev) { - unsigned int frags = skb_shinfo(skb)->nr_frags; struct rtl8169_private *tp = netdev_priv(dev); unsigned int entry = tp->cur_tx % NUM_TX_DESC; struct TxDesc *txd_first, *txd_last; bool stop_queue, door_bell; + unsigned int frags; u32 opts[2];
if (unlikely(!rtl_tx_slots_avail(tp))) { @@ -4305,6 +4305,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,
txd_first = tp->TxDescArray + entry;
+ frags = skb_shinfo(skb)->nr_frags; if (frags) { if (rtl8169_xmit_frags(tp, skb, opts, entry)) goto err_dma_1;