Description
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: fix MSG_ZEROCOPY pinned-pages accounting virtio_transport_init_zcopy_skb() uses iter->count as the size argument for msg_zerocopy_realloc(), which in turn passes it to mm_account_pinned_pages() for RLIMIT_MEMLOCK accounting. However, this function is called after virtio_transport_fill_skb() has already consumed the iterator via __zerocopy_sg_from_iter(), so on the last skb, iter->count will be 0, skipping the RLIMIT_MEMLOCK enforcement. Pass pkt_len (the total bytes being sent) as an explicit parameter to virtio_transport_init_zcopy_skb() instead of reading the already-consumed iter->count. This matches TCP and UDP, which both call msg_zerocopy_realloc() with the original message size.
Affected products
- Linux / Linux581512a6dc939ef122e49336626ae159f3b8a345 – 6af1736b5810bc8a4a43a8518530113f5a757dc1
- Linux / Linux581512a6dc939ef122e49336626ae159f3b8a345 – d0117950075f0a9d5944980784c719d8ebcd4bff
- Linux / Linux581512a6dc939ef122e49336626ae159f3b8a345 – 1cb36e252211506f51095fe7ced8286cc77b4c80
- Linux / Linux6.7 – 6.7
- Linux / Linux0 – 6.7
- Linux / Linux6.18.33 – 6.18.*
- Linux / Linux7.0.10 – 7.0.*
- Linux / Linux7.1 – *