| Message ID | 20240923214949.231511-2-olek2@wp.pl (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 45c0de18ff2dc9af01236380404bbd6a46502c69 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: ethernet: lantiq_etop: fix memory disclosure | expand |
> -----Original Message----- > From: Aleksander Jan Bajkowski <olek2@wp.pl> > Sent: Monday, September 23, 2024 2:50 PM > To: davem@davemloft.net; edumazet@google.com; kuba@kernel.org; > pabeni@redhat.com; olek2@wp.pl; horms@kernel.org; Keller, Jacob E > <jacob.e.keller@intel.com>; john@phrozen.org; ralf@linux-mips.org; > ralph.hempel@lantiq.com; netdev@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: [PATCH net v3 1/1] net: ethernet: lantiq_etop: fix memory disclosure > > When applying padding, the buffer is not zeroed, which results in memory > disclosure. The mentioned data is observed on the wire. This patch uses > skb_put_padto() to pad Ethernet frames properly. The mentioned function > zeroes the expanded buffer. > > In case the packet cannot be padded it is silently dropped. Statistics > are also not incremented. This driver does not support statistics in the > old 32-bit format or the new 64-bit format. These will be added in the > future. In its current form, the patch should be easily backported to > stable versions. > > Ethernet MACs on Amazon-SE and Danube cannot do padding of the packets > in hardware, so software padding must be applied. > > Fixes: 504d4721ee8e ("MIPS: Lantiq: Add ethernet driver") > Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl> > --- Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
On 9/23/24 14:49, Aleksander Jan Bajkowski wrote: > When applying padding, the buffer is not zeroed, which results in memory > disclosure. The mentioned data is observed on the wire. This patch uses > skb_put_padto() to pad Ethernet frames properly. The mentioned function > zeroes the expanded buffer. > > In case the packet cannot be padded it is silently dropped. Statistics > are also not incremented. This driver does not support statistics in the > old 32-bit format or the new 64-bit format. These will be added in the > future. In its current form, the patch should be easily backported to > stable versions. > > Ethernet MACs on Amazon-SE and Danube cannot do padding of the packets > in hardware, so software padding must be applied. > > Fixes: 504d4721ee8e ("MIPS: Lantiq: Add ethernet driver") > Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Thanks for taking in the suggsetion!
On 9/23/24 23:49, Aleksander Jan Bajkowski wrote: > When applying padding, the buffer is not zeroed, which results in memory > disclosure. The mentioned data is observed on the wire. This patch uses > skb_put_padto() to pad Ethernet frames properly. The mentioned function > zeroes the expanded buffer. > > In case the packet cannot be padded it is silently dropped. Statistics > are also not incremented. This driver does not support statistics in the > old 32-bit format or the new 64-bit format. These will be added in the > future. In its current form, the patch should be easily backported to > stable versions. > > Ethernet MACs on Amazon-SE and Danube cannot do padding of the packets > in hardware, so software padding must be applied. > > Fixes: 504d4721ee8e ("MIPS: Lantiq: Add ethernet driver") > Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl> For future submissions, please avoid adding the cover letter in case of a single patch. Thanks, Paolo
diff --git a/drivers/net/ethernet/lantiq_etop.c b/drivers/net/ethernet/lantiq_etop.c index 3c289bfe0a09..7179271f63b6 100644 --- a/drivers/net/ethernet/lantiq_etop.c +++ b/drivers/net/ethernet/lantiq_etop.c @@ -481,7 +481,9 @@ ltq_etop_tx(struct sk_buff *skb, struct net_device *dev) unsigned long flags; u32 byte_offset; - len = skb->len < ETH_ZLEN ? ETH_ZLEN : skb->len; + if (skb_put_padto(skb, ETH_ZLEN)) + return NETDEV_TX_OK; + len = skb->len; if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) || ch->skb[ch->dma.desc]) { netdev_err(dev, "tx ring full\n");
When applying padding, the buffer is not zeroed, which results in memory disclosure. The mentioned data is observed on the wire. This patch uses skb_put_padto() to pad Ethernet frames properly. The mentioned function zeroes the expanded buffer. In case the packet cannot be padded it is silently dropped. Statistics are also not incremented. This driver does not support statistics in the old 32-bit format or the new 64-bit format. These will be added in the future. In its current form, the patch should be easily backported to stable versions. Ethernet MACs on Amazon-SE and Danube cannot do padding of the packets in hardware, so software padding must be applied. Fixes: 504d4721ee8e ("MIPS: Lantiq: Add ethernet driver") Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl> --- drivers/net/ethernet/lantiq_etop.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)