When e1000e_setup_rx_resources is failed in e1000_open,
e1000e_free_tx_resources in "err_setup_rx" segment is executed.
"writel(0, tx_ring->head)" statement in e1000_clean_tx_ring
in e1000e_free_tx_resources will cause a null poonter dereference(crash),
because "tx_ring->head" is only assigned in e1000_configure_tx
in e1000_configure, but it is after e1000e_setup_rx_resources.
This patch moves head/tail register writing to e1000_configure_tx/rx,
which can fix this problem. It is inspired by igb_configure_tx_ring
in the igb driver.
Specially, thank Alexander Duyck for his valuable suggestion.
Signed-off-by: Jia-Ju Bai <[email protected]>
---
drivers/net/ethernet/intel/e1000e/netdev.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 89d788d..3aee51b 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -1737,12 +1737,6 @@ static void e1000_clean_rx_ring(struct e1000_ring *rx_ring)
rx_ring->next_to_clean = 0;
rx_ring->next_to_use = 0;
adapter->flags2 &= ~FLAG2_IS_DISCARDING;
-
- writel(0, rx_ring->head);
- if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
- e1000e_update_rdt_wa(rx_ring, 0);
- else
- writel(0, rx_ring->tail);
}
static void e1000e_downshift_workaround(struct work_struct *work)
@@ -2447,12 +2441,6 @@ static void e1000_clean_tx_ring(struct e1000_ring *tx_ring)
tx_ring->next_to_use = 0;
tx_ring->next_to_clean = 0;
-
- writel(0, tx_ring->head);
- if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
- e1000e_update_tdt_wa(tx_ring, 0);
- else
- writel(0, tx_ring->tail);
}
/**
@@ -2954,6 +2942,12 @@ static void e1000_configure_tx(struct e1000_adapter *adapter)
tx_ring->head = adapter->hw.hw_addr + E1000_TDH(0);
tx_ring->tail = adapter->hw.hw_addr + E1000_TDT(0);
+ writel(0, tx_ring->head);
+ if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
+ e1000e_update_tdt_wa(tx_ring, 0);
+ else
+ writel(0, tx_ring->tail);
+
/* Set the Tx Interrupt Delay register */
ew32(TIDV, adapter->tx_int_delay);
/* Tx irq moderation */
@@ -3275,6 +3269,12 @@ static void e1000_configure_rx(struct e1000_adapter *adapter)
rx_ring->head = adapter->hw.hw_addr + E1000_RDH(0);
rx_ring->tail = adapter->hw.hw_addr + E1000_RDT(0);
+ writel(0, rx_ring->head);
+ if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
+ e1000e_update_rdt_wa(rx_ring, 0);
+ else
+ writel(0, rx_ring->tail);
+
/* Enable Receive Checksum Offload for TCP and UDP */
rxcsum = er32(RXCSUM);
if (adapter->netdev->features & NETIF_F_RXCSUM)
--
1.7.9.5
On Wed, 2015-08-05 at 18:16 +0800, Jia-Ju Bai wrote:
> When e1000e_setup_rx_resources is failed in e1000_open,
> e1000e_free_tx_resources in "err_setup_rx" segment is executed.
> "writel(0, tx_ring->head)" statement in e1000_clean_tx_ring
> in e1000e_free_tx_resources will cause a null poonter
> dereference(crash),
> because "tx_ring->head" is only assigned in e1000_configure_tx
> in e1000_configure, but it is after e1000e_setup_rx_resources.
>
> This patch moves head/tail register writing to e1000_configure_tx/rx,
> which can fix this problem. It is inspired by igb_configure_tx_ring
> in the igb driver.
>
> Specially, thank Alexander Duyck for his valuable suggestion.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>
> ---
> drivers/net/ethernet/intel/e1000e/netdev.c | 24
> ++++++++++++------------
> 1 file changed, 12 insertions(+), 12 deletions(-)
Is your intention that this patch replace the existing patch:
http://patchwork.ozlabs.org/patch/502990/
...which is currently in my queue?
On 08/05/2015 06:43 PM, Jeff Kirsher wrote:
>
> Is your intention that this patch replace the existing patch:
> http://patchwork.ozlabs.org/patch/502990/
> ...which is currently in my queue?
>
Okay, please replace the previous patch.
> From: Intel-wired-lan [mailto:[email protected]] On
> Behalf Of Jia-Ju Bai
> Sent: Wednesday, August 05, 2015 3:16 AM
> To: Kirsher, Jeffrey T; Brandeburg, Jesse
> Cc: [email protected]; Jia-Ju Bai; [email protected];
> [email protected]
> Subject: [Intel-wired-lan] [PATCH v2] e1000e: Modify tx/rx configurations
> to avoid null pointer dereferences in e1000_open
>
> When e1000e_setup_rx_resources is failed in e1000_open,
> e1000e_free_tx_resources in "err_setup_rx" segment is executed.
> "writel(0, tx_ring->head)" statement in e1000_clean_tx_ring
> in e1000e_free_tx_resources will cause a null poonter dereference(crash),
> because "tx_ring->head" is only assigned in e1000_configure_tx
> in e1000_configure, but it is after e1000e_setup_rx_resources.
>
> This patch moves head/tail register writing to e1000_configure_tx/rx,
> which can fix this problem. It is inspired by igb_configure_tx_ring
> in the igb driver.
>
> Specially, thank Alexander Duyck for his valuable suggestion.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>
> ---
> drivers/net/ethernet/intel/e1000e/netdev.c | 24 ++++++++++++-----------
> -
> 1 file changed, 12 insertions(+), 12 deletions(-)
Tested-by: Aaron Brown <[email protected]>