[U-Boot] [PATCH] api: net: fix length check in eth_receive()
If the requested length is too small to hold the received packet, eth_receive() will return -1 and will leave the packet in the receive buffers. Instead of returning an error in this case, we return the first portion of the received packet and remove it from the receive buffers.
This fixes FreeBSD's ubldr. Without this patch it will just stop receiving packets if the NIC receives more than PKTBUFSRX too large packets.
Signed-off-by: Michael Walle michael@walle.cc Cc: Joe Hershberger joe.hershberger@gmail.com Cc: Rafal Jaworowski raj@semihalf.com Cc: Piotr Kruszynski ppk@semihalf.com --- net/eth.c | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-)
diff --git a/net/eth.c b/net/eth.c index d526264..09249c9 100644 --- a/net/eth.c +++ b/net/eth.c @@ -486,10 +486,7 @@ int eth_receive(void *packet, int length) return -1; }
- if (length < eth_rcv_bufs[eth_rcv_current].length) - return -1; - - length = eth_rcv_bufs[eth_rcv_current].length; + length = min(eth_rcv_bufs[eth_rcv_current].length, length);
for (i = 0; i < length; i++) p[i] = eth_rcv_bufs[eth_rcv_current].data[i];
Hi Michael,
On Fri, Jun 22, 2012 at 4:24 PM, Michael Walle michael@walle.cc wrote:
If the requested length is too small to hold the received packet, eth_receive() will return -1 and will leave the packet in the receive buffers. Instead of returning an error in this case, we return the first portion of the received packet and remove it from the receive buffers.
This fixes FreeBSD's ubldr. Without this patch it will just stop receiving packets if the NIC receives more than PKTBUFSRX too large packets.
Signed-off-by: Michael Walle michael@walle.cc Cc: Joe Hershberger joe.hershberger@gmail.com Cc: Rafal Jaworowski raj@semihalf.com Cc: Piotr Kruszynski ppk@semihalf.com
net/eth.c | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-)
diff --git a/net/eth.c b/net/eth.c index d526264..09249c9 100644 --- a/net/eth.c +++ b/net/eth.c @@ -486,10 +486,7 @@ int eth_receive(void *packet, int length) return -1; }
- if (length < eth_rcv_bufs[eth_rcv_current].length)
- return -1;
- length = eth_rcv_bufs[eth_rcv_current].length;
- length = min(eth_rcv_bufs[eth_rcv_current].length, length);
Is it really a good idea to return a runt packet to the network protocols? I understand wanting to drop the too-big packet, but I think you should simply drop that packet before returning the error, but still error.
-Joe
[removed Piotr Kruszynski from CC because mail address does not exist anymore]
Hi Joe,
Am Montag 25 Juni 2012, 22:25:56 schrieb Joe Hershberger:
Hi Michael,
On Fri, Jun 22, 2012 at 4:24 PM, Michael Walle michael@walle.cc wrote:
If the requested length is too small to hold the received packet, eth_receive() will return -1 and will leave the packet in the receive buffers. Instead of returning an error in this case, we return the first portion of the received packet and remove it from the receive buffers.
This fixes FreeBSD's ubldr. Without this patch it will just stop receiving packets if the NIC receives more than PKTBUFSRX too large packets.
Signed-off-by: Michael Walle michael@walle.cc Cc: Joe Hershberger joe.hershberger@gmail.com Cc: Rafal Jaworowski raj@semihalf.com Cc: Piotr Kruszynski ppk@semihalf.com
net/eth.c | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-)
diff --git a/net/eth.c b/net/eth.c index d526264..09249c9 100644 --- a/net/eth.c +++ b/net/eth.c @@ -486,10 +486,7 @@ int eth_receive(void *packet, int length) return -1; }
if (length < eth_rcv_bufs[eth_rcv_current].length)return -1;length = eth_rcv_bufs[eth_rcv_current].length;
length = min(eth_rcv_bufs[eth_rcv_current].length, length);Is it really a good idea to return a runt packet to the network protocols? I understand wanting to drop the too-big packet, but I think you should simply drop that packet before returning the error, but still error.
its the same behaviour as recv() with udp packets, isn't it? see http://pubs.opengroup.org/onlinepubs/009695399/functions/recv.html
But i'm not set on this, maybe rafal could clarify this. My main point is to make ubldr working ;)
Hi Michael,
On Mon, Jun 25, 2012 at 3:50 PM, Michael Walle michael@walle.cc wrote:
[removed Piotr Kruszynski from CC because mail address does not exist anymore]
Hi Joe,
Am Montag 25 Juni 2012, 22:25:56 schrieb Joe Hershberger:
Hi Michael,
On Fri, Jun 22, 2012 at 4:24 PM, Michael Walle michael@walle.cc wrote:
If the requested length is too small to hold the received packet, eth_receive() will return -1 and will leave the packet in the receive buffers. Instead of returning an error in this case, we return the first portion of the received packet and remove it from the receive buffers.
This fixes FreeBSD's ubldr. Without this patch it will just stop receiving packets if the NIC receives more than PKTBUFSRX too large packets.
Signed-off-by: Michael Walle michael@walle.cc Cc: Joe Hershberger joe.hershberger@gmail.com Cc: Rafal Jaworowski raj@semihalf.com Cc: Piotr Kruszynski ppk@semihalf.com
Applied, thanks.
-Joe
participants (2)
-
Joe Hershberger -
Michael Walle