In the Linux kernel, the following vulnerability has been resolved:

net: stmmac: clear stale buf->page after recycling on skb build failure

In stmmac_rx(), when napi_build_skb() fails the descriptor page is recycled back to the page pool with page_pool_recycle_direct(), but buf->page is left pointing at the recycled page, unlike every other consumption site in the function which clears the pointer after handing the page away.

With the stale pointer stmmac_rx_refill() skips the replacement allocation and programs the already-recycled page back into the RX descriptor.

Clear buf->page on the napi_build_skb() failure path to keep the buffer lifecycle consistent with the other consumption sites.

In the Linux kernel, the following vulnerability has been resolved:

net: stmmac: clear stale buf->page after recycling on skb build failure

In stmmac_rx(), when napi_build_skb() fails the descriptor page is recycled back to the page pool with page_pool_recycle_direct(), but buf->page is left pointing at the recycled page, unlike every other consumption site in the function which clears the pointer after handing the page away.

With the stale pointer stmmac_rx_refill() skips the replacement allocation and programs the already-recycled page back into the RX descriptor.

Clear buf->page on the napi_build_skb() failure path to keep the buffer lifecycle consistent with the other consumption sites.

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 120 more

In the Linux kernel, the following vulnerability has been resolved: net: stmmac: clear stale buf->page after recycling on skb build failure In stmmac_rx(), when napi_build_skb() fails the descriptor page is recycled back to the page pool with page_pool_recycle_direct(), but buf->page is left pointing at the recycled page, unlike every other consumption site in the function which clears the pointer after handing the page away. With the stale pointer stmmac_rx_refill() skips the replacement allocation and programs the already-recycled page back into the RX descriptor. Clear buf->page on the napi_build_skb() failure path to keep the buffer lifecycle consistent with the other consumption sites.

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, möglicherweise einen Denial-of-Service-Angriff auszulösen, Daten zu manipulieren oder offenzulegen oder Sicherheitsmaßnahmen zu umgehen.