diff mbox

net: return value of skb_linearize should be handled in Linux kernel

Message ID 1481008233-16777-1-git-send-email-zhouzhouyi@gmail.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Zhouyi Zhou Dec. 6, 2016, 7:10 a.m. UTC
kmalloc_reserve may fail to allocate memory inside skb_linearize, 
which means skb_linearize's return value should not be ignored. 
Following patch correct the uses of skb_linearize.

Compiled in x86_64

Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
---
 drivers/infiniband/hw/nes/nes_nic.c           | 5 +++--
 drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c | 6 +++++-
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 3 +--
 drivers/scsi/bnx2fc/bnx2fc_fcoe.c             | 7 +++++--
 drivers/scsi/fcoe/fcoe.c                      | 5 ++++-
 net/tipc/link.c                               | 3 ++-
 net/tipc/name_distr.c                         | 5 ++++-
 7 files changed, 24 insertions(+), 10 deletions(-)

Comments

Yuval Shaia Dec. 6, 2016, 4:57 p.m. UTC | #1
On Tue, Dec 06, 2016 at 03:10:33PM +0800, Zhouyi Zhou wrote:
> kmalloc_reserve may fail to allocate memory inside skb_linearize, 
> which means skb_linearize's return value should not be ignored. 
> Following patch correct the uses of skb_linearize.
> 
> Compiled in x86_64

FWIW compiled also on SPARC

Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>

> 
> Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
> ---
>  drivers/infiniband/hw/nes/nes_nic.c           | 5 +++--
>  drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c | 6 +++++-
>  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 3 +--
>  drivers/scsi/bnx2fc/bnx2fc_fcoe.c             | 7 +++++--
>  drivers/scsi/fcoe/fcoe.c                      | 5 ++++-
>  net/tipc/link.c                               | 3 ++-
>  net/tipc/name_distr.c                         | 5 ++++-
>  7 files changed, 24 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/infiniband/hw/nes/nes_nic.c b/drivers/infiniband/hw/nes/nes_nic.c
> index 2b27d13..69372ea 100644
> --- a/drivers/infiniband/hw/nes/nes_nic.c
> +++ b/drivers/infiniband/hw/nes/nes_nic.c
> @@ -662,10 +662,11 @@ static int nes_netdev_start_xmit(struct sk_buff *skb, struct net_device *netdev)
>  				nesnic->sq_head &= nesnic->sq_size-1;
>  			}
>  		} else {
> -			nesvnic->linearized_skbs++;
>  			hoffset = skb_transport_header(skb) - skb->data;
>  			nhoffset = skb_network_header(skb) - skb->data;
> -			skb_linearize(skb);
> +			if (skb_linearize(skb))
> +				return NETDEV_TX_BUSY;
> +			nesvnic->linearized_skbs++;
>  			skb_set_transport_header(skb, hoffset);
>  			skb_set_network_header(skb, nhoffset);
>  			if (!nes_nic_send(skb, netdev))
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
> index 2a653ec..ab787cb 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
> @@ -490,7 +490,11 @@ int ixgbe_fcoe_ddp(struct ixgbe_adapter *adapter,
>  	 */
>  	if ((fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA) &&
>  	    (fctl & FC_FC_END_SEQ)) {
> -		skb_linearize(skb);
> +		int err = 0;
> +
> +		err = skb_linearize(skb);
> +		if (err)
> +			return err;
>  		crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
>  		crc->fcoe_eof = FC_EOF_T;
>  	}
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index fee1f29..4926d48 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -2173,8 +2173,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>  				total_rx_bytes += ddp_bytes;
>  				total_rx_packets += DIV_ROUND_UP(ddp_bytes,
>  								 mss);
> -			}
> -			if (!ddp_bytes) {
> +			} else {
>  				dev_kfree_skb_any(skb);
>  				continue;
>  			}
> diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
> index f9ddb61..197d02e 100644
> --- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
> +++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
> @@ -542,8 +542,11 @@ static void bnx2fc_recv_frame(struct sk_buff *skb)
>  		return;
>  	}
>  
> -	if (skb_is_nonlinear(skb))
> -		skb_linearize(skb);
> +	if (skb_linearize(skb)) {
> +		kfree_skb(skb);
> +		return;
> +	}
> +
>  	mac = eth_hdr(skb)->h_source;
>  	dest_mac = eth_hdr(skb)->h_dest;
>  
> diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
> index 9bd41a3..f691b97 100644
> --- a/drivers/scsi/fcoe/fcoe.c
> +++ b/drivers/scsi/fcoe/fcoe.c
> @@ -1685,7 +1685,10 @@ static void fcoe_recv_frame(struct sk_buff *skb)
>  			skb->dev ? skb->dev->name : "<NULL>");
>  
>  	port = lport_priv(lport);
> -	skb_linearize(skb); /* check for skb_is_nonlinear is within skb_linearize */
> +	if (skb_linearize(skb)) {
> +		kfree_skb(skb);
> +		return;
> +	}
>  
>  	/*
>  	 * Frame length checks and setting up the header pointers
> diff --git a/net/tipc/link.c b/net/tipc/link.c
> index bda89bf..077c570 100644
> --- a/net/tipc/link.c
> +++ b/net/tipc/link.c
> @@ -1446,7 +1446,8 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
>  	if (tipc_own_addr(l->net) > msg_prevnode(hdr))
>  		l->net_plane = msg_net_plane(hdr);
>  
> -	skb_linearize(skb);
> +	if (skb_linearize(skb))
> +		goto exit;
>  	hdr = buf_msg(skb);
>  	data = msg_data(hdr);
>  
> diff --git a/net/tipc/name_distr.c b/net/tipc/name_distr.c
> index c1cfd92..4e05d2a 100644
> --- a/net/tipc/name_distr.c
> +++ b/net/tipc/name_distr.c
> @@ -356,7 +356,10 @@ void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq)
>  
>  	spin_lock_bh(&tn->nametbl_lock);
>  	for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) {
> -		skb_linearize(skb);
> +		if (skb_linearize(skb)) {
> +			kfree_skb(skb);
> +			continue;
> +		}
>  		msg = buf_msg(skb);
>  		mtype = msg_type(msg);
>  		item = (struct distr_item *)msg_data(msg);
> -- 
> 1.9.1
> 
> --
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Cong Wang Dec. 7, 2016, 5:02 a.m. UTC | #2
On Mon, Dec 5, 2016 at 11:10 PM, Zhouyi Zhou <zhouzhouyi@gmail.com> wrote:
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
> index 2a653ec..ab787cb 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
> @@ -490,7 +490,11 @@ int ixgbe_fcoe_ddp(struct ixgbe_adapter *adapter,
>          */
>         if ((fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA) &&
>             (fctl & FC_FC_END_SEQ)) {
> -               skb_linearize(skb);
> +               int err = 0;
> +
> +               err = skb_linearize(skb);
> +               if (err)
> +                       return err;


You can reuse 'rc' instead of adding 'err'.



>                 crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
>                 crc->fcoe_eof = FC_EOF_T;
>         }
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index fee1f29..4926d48 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -2173,8 +2173,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>                                 total_rx_bytes += ddp_bytes;
>                                 total_rx_packets += DIV_ROUND_UP(ddp_bytes,
>                                                                  mss);
> -                       }
> -                       if (!ddp_bytes) {
> +                       } else {
>                                 dev_kfree_skb_any(skb);
>                                 continue;
>                         }


This piece doesn't seem to be related.
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Zhouyi Zhou Dec. 7, 2016, 6:27 a.m. UTC | #3
On Wed, Dec 7, 2016 at 1:02 PM, Cong Wang <xiyou.wangcong@gmail.com> wrote:
> On Mon, Dec 5, 2016 at 11:10 PM, Zhouyi Zhou <zhouzhouyi@gmail.com> wrote:
>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
>> index 2a653ec..ab787cb 100644
>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
>> @@ -490,7 +490,11 @@ int ixgbe_fcoe_ddp(struct ixgbe_adapter *adapter,
>>          */
>>         if ((fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA) &&
>>             (fctl & FC_FC_END_SEQ)) {
>> -               skb_linearize(skb);
>> +               int err = 0;
>> +
>> +               err = skb_linearize(skb);
>> +               if (err)
>> +                       return err;
>
>
> You can reuse 'rc' instead of adding 'err'.
rc here is meaningful for the length of data being ddped. If using rc
here, a successful
skb_linearize will assign rc to 0.
>
>
>
>>                 crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
>>                 crc->fcoe_eof = FC_EOF_T;
>>         }
>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>> index fee1f29..4926d48 100644
>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>> @@ -2173,8 +2173,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>>                                 total_rx_bytes += ddp_bytes;
>>                                 total_rx_packets += DIV_ROUND_UP(ddp_bytes,
>>                                                                  mss);
>> -                       }
>> -                       if (!ddp_bytes) {
>> +                       } else {
>>                                 dev_kfree_skb_any(skb);
>>                                 continue;
>>                         }
>
>
> This piece doesn't seem to be related.
if ddp_bytes is negative there will be some error, I think the skb
should not pass to upper layer.
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Eric Dumazet Dec. 7, 2016, 6:51 a.m. UTC | #4
On Tue, 2016-12-06 at 15:10 +0800, Zhouyi Zhou wrote:
> kmalloc_reserve may fail to allocate memory inside skb_linearize, 
> which means skb_linearize's return value should not be ignored. 
> Following patch correct the uses of skb_linearize.
> 
> Compiled in x86_64
> 
> Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
> ---
>  drivers/infiniband/hw/nes/nes_nic.c           | 5 +++--
>  drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c | 6 +++++-
>  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 3 +--
>  drivers/scsi/bnx2fc/bnx2fc_fcoe.c             | 7 +++++--
>  drivers/scsi/fcoe/fcoe.c                      | 5 ++++-
>  net/tipc/link.c                               | 3 ++-
>  net/tipc/name_distr.c                         | 5 ++++-
>  7 files changed, 24 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/infiniband/hw/nes/nes_nic.c b/drivers/infiniband/hw/nes/nes_nic.c
> index 2b27d13..69372ea 100644
> --- a/drivers/infiniband/hw/nes/nes_nic.c
> +++ b/drivers/infiniband/hw/nes/nes_nic.c
> @@ -662,10 +662,11 @@ static int nes_netdev_start_xmit(struct sk_buff *skb, struct net_device *netdev)
>  				nesnic->sq_head &= nesnic->sq_size-1;
>  			}
>  		} else {
> -			nesvnic->linearized_skbs++;
>  			hoffset = skb_transport_header(skb) - skb->data;
>  			nhoffset = skb_network_header(skb) - skb->data;
> -			skb_linearize(skb);
> +			if (skb_linearize(skb))
> +				return NETDEV_TX_BUSY;

This would live lock.

Please drop the packet.

You probably should send one patch per driver, to ease code review and
acceptance.



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Cong Wang Dec. 7, 2016, 5:57 p.m. UTC | #5
On Tue, Dec 6, 2016 at 10:27 PM, Zhouyi Zhou <zhouzhouyi@gmail.com> wrote:
> On Wed, Dec 7, 2016 at 1:02 PM, Cong Wang <xiyou.wangcong@gmail.com> wrote:
>> On Mon, Dec 5, 2016 at 11:10 PM, Zhouyi Zhou <zhouzhouyi@gmail.com> wrote:
>>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
>>> index 2a653ec..ab787cb 100644
>>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
>>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
>>> @@ -490,7 +490,11 @@ int ixgbe_fcoe_ddp(struct ixgbe_adapter *adapter,
>>>          */
>>>         if ((fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA) &&
>>>             (fctl & FC_FC_END_SEQ)) {
>>> -               skb_linearize(skb);
>>> +               int err = 0;
>>> +
>>> +               err = skb_linearize(skb);
>>> +               if (err)
>>> +                       return err;
>>
>>
>> You can reuse 'rc' instead of adding 'err'.
> rc here is meaningful for the length of data being ddped. If using rc
> here, a successful
> skb_linearize will assign rc to 0.

Right, I thought it returns 0 on success.


>>
>>
>>
>>>                 crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
>>>                 crc->fcoe_eof = FC_EOF_T;
>>>         }
>>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>>> index fee1f29..4926d48 100644
>>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>>> @@ -2173,8 +2173,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>>>                                 total_rx_bytes += ddp_bytes;
>>>                                 total_rx_packets += DIV_ROUND_UP(ddp_bytes,
>>>                                                                  mss);
>>> -                       }
>>> -                       if (!ddp_bytes) {
>>> +                       } else {
>>>                                 dev_kfree_skb_any(skb);
>>>                                 continue;
>>>                         }
>>
>>
>> This piece doesn't seem to be related.
> if ddp_bytes is negative there will be some error, I think the skb
> should not pass to upper layer.

You misunderstand my point, this return value is for ixgbe_fcoe_ddp()
not skb_linearize(), you need to make it a separate patch because this
patch, as in $subject, only fixes skb_linearize().
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diff mbox

Patch

diff --git a/drivers/infiniband/hw/nes/nes_nic.c b/drivers/infiniband/hw/nes/nes_nic.c
index 2b27d13..69372ea 100644
--- a/drivers/infiniband/hw/nes/nes_nic.c
+++ b/drivers/infiniband/hw/nes/nes_nic.c
@@ -662,10 +662,11 @@  static int nes_netdev_start_xmit(struct sk_buff *skb, struct net_device *netdev)
 				nesnic->sq_head &= nesnic->sq_size-1;
 			}
 		} else {
-			nesvnic->linearized_skbs++;
 			hoffset = skb_transport_header(skb) - skb->data;
 			nhoffset = skb_network_header(skb) - skb->data;
-			skb_linearize(skb);
+			if (skb_linearize(skb))
+				return NETDEV_TX_BUSY;
+			nesvnic->linearized_skbs++;
 			skb_set_transport_header(skb, hoffset);
 			skb_set_network_header(skb, nhoffset);
 			if (!nes_nic_send(skb, netdev))
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
index 2a653ec..ab787cb 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
@@ -490,7 +490,11 @@  int ixgbe_fcoe_ddp(struct ixgbe_adapter *adapter,
 	 */
 	if ((fh->fh_r_ctl == FC_RCTL_DD_SOL_DATA) &&
 	    (fctl & FC_FC_END_SEQ)) {
-		skb_linearize(skb);
+		int err = 0;
+
+		err = skb_linearize(skb);
+		if (err)
+			return err;
 		crc = (struct fcoe_crc_eof *)skb_put(skb, sizeof(*crc));
 		crc->fcoe_eof = FC_EOF_T;
 	}
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index fee1f29..4926d48 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -2173,8 +2173,7 @@  static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
 				total_rx_bytes += ddp_bytes;
 				total_rx_packets += DIV_ROUND_UP(ddp_bytes,
 								 mss);
-			}
-			if (!ddp_bytes) {
+			} else {
 				dev_kfree_skb_any(skb);
 				continue;
 			}
diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
index f9ddb61..197d02e 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
@@ -542,8 +542,11 @@  static void bnx2fc_recv_frame(struct sk_buff *skb)
 		return;
 	}
 
-	if (skb_is_nonlinear(skb))
-		skb_linearize(skb);
+	if (skb_linearize(skb)) {
+		kfree_skb(skb);
+		return;
+	}
+
 	mac = eth_hdr(skb)->h_source;
 	dest_mac = eth_hdr(skb)->h_dest;
 
diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 9bd41a3..f691b97 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -1685,7 +1685,10 @@  static void fcoe_recv_frame(struct sk_buff *skb)
 			skb->dev ? skb->dev->name : "<NULL>");
 
 	port = lport_priv(lport);
-	skb_linearize(skb); /* check for skb_is_nonlinear is within skb_linearize */
+	if (skb_linearize(skb)) {
+		kfree_skb(skb);
+		return;
+	}
 
 	/*
 	 * Frame length checks and setting up the header pointers
diff --git a/net/tipc/link.c b/net/tipc/link.c
index bda89bf..077c570 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1446,7 +1446,8 @@  static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 	if (tipc_own_addr(l->net) > msg_prevnode(hdr))
 		l->net_plane = msg_net_plane(hdr);
 
-	skb_linearize(skb);
+	if (skb_linearize(skb))
+		goto exit;
 	hdr = buf_msg(skb);
 	data = msg_data(hdr);
 
diff --git a/net/tipc/name_distr.c b/net/tipc/name_distr.c
index c1cfd92..4e05d2a 100644
--- a/net/tipc/name_distr.c
+++ b/net/tipc/name_distr.c
@@ -356,7 +356,10 @@  void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq)
 
 	spin_lock_bh(&tn->nametbl_lock);
 	for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) {
-		skb_linearize(skb);
+		if (skb_linearize(skb)) {
+			kfree_skb(skb);
+			continue;
+		}
 		msg = buf_msg(skb);
 		mtype = msg_type(msg);
 		item = (struct distr_item *)msg_data(msg);