| Message ID | 20240620122311.424811-1-qq810974084@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [V2] hippi: fix possible buffer overflow caused by bad DMA value in rr_start_xmit() | expand |
>The value rrpriv->info->tx_ctrl is stored in DMA memory, and it is assigned to txctrl, >so txctrl->pi can be modified at any time by malicious hardware. Becausetxctrl->pi is >assigned to index, buffer overflow may occur when the code "rrpriv- >>tx_skbuff[index]" is executed. > >To address this issue, the index should be checked. > >Fixes: f33a7251c825 ("hippi: switch from 'pci_' to 'dma_' API") >Signed-off-by: Huai-Yuan Liu <qq810974084@gmail.com> >--- >V2: >* In patch V2, we remove the first condition in if statement and use > netdev_err() instead of printk(). > Thanks Paolo Abeni for helpful advice. >--- > drivers/net/hippi/rrunner.c | 5 +++++ > 1 file changed, 5 insertions(+) > >diff --git a/drivers/net/hippi/rrunner.c b/drivers/net/hippi/rrunner.c index >aa8f828a0ae7..6b0056ced922 100644 >--- a/drivers/net/hippi/rrunner.c >+++ b/drivers/net/hippi/rrunner.c >@@ -1440,6 +1440,11 @@ static netdev_tx_t rr_start_xmit(struct sk_buff *skb, > txctrl = &rrpriv->info->tx_ctrl; > > index = txctrl->pi; >+ if (index >= TX_RING_ENTRIES) { >+ netdev_err(dev, "invalid index value %02x\n", index); Much better would be to use netif_msg_tx_err which can be enabled/disabled instead of dumping on console, which would be annoying if there are many errors. Thanks, Sunil.
On Fri, 21 Jun 2024 05:11:41 +0000 Sunil Kovvuri Goutham wrote: > >+ if (index >= TX_RING_ENTRIES) { > >+ netdev_err(dev, "invalid index value %02x\n", index); > > Much better would be to use netif_msg_tx_err which can be > enabled/disabled instead of dumping on console, which would be > annoying if there are many errors. Doesn't it require ethtool to be changed tho? This driver doesn't have any ethtool ops AFAICT. I'd go for netdev_err_once(). But more importantly, I think you should stop the queue before returning BUSY.
diff --git a/drivers/net/hippi/rrunner.c b/drivers/net/hippi/rrunner.c index aa8f828a0ae7..6b0056ced922 100644 --- a/drivers/net/hippi/rrunner.c +++ b/drivers/net/hippi/rrunner.c @@ -1440,6 +1440,11 @@ static netdev_tx_t rr_start_xmit(struct sk_buff *skb, txctrl = &rrpriv->info->tx_ctrl; index = txctrl->pi; + if (index >= TX_RING_ENTRIES) { + netdev_err(dev, "invalid index value %02x\n", index); + spin_unlock_irqrestore(&rrpriv->lock, flags); + return NETDEV_TX_BUSY; + } rrpriv->tx_skbuff[index] = skb; set_rraddr(&rrpriv->tx_ring[index].addr,
The value rrpriv->info->tx_ctrl is stored in DMA memory, and it is assigned to txctrl, so txctrl->pi can be modified at any time by malicious hardware. Becausetxctrl->pi is assigned to index, buffer overflow may occur when the code "rrpriv->tx_skbuff[index]" is executed. To address this issue, the index should be checked. Fixes: f33a7251c825 ("hippi: switch from 'pci_' to 'dma_' API") Signed-off-by: Huai-Yuan Liu <qq810974084@gmail.com> --- V2: * In patch V2, we remove the first condition in if statement and use netdev_err() instead of printk(). Thanks Paolo Abeni for helpful advice. --- drivers/net/hippi/rrunner.c | 5 +++++ 1 file changed, 5 insertions(+)