diff options
| author | Stefano Garzarella <sgarzare@redhat.com> | 2026-05-27 19:10:46 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-05-28 14:44:21 -0700 |
| commit | e03f0b53b4bd51b70e48e3548bd1163e8496ff9e (patch) | |
| tree | 49ec7b92f02cfcc28a63ddbeee1f08969c1fb597 /net | |
| parent | 1f03da8aea6e8d29533f0aa334f173759daac771 (diff) | |
| download | linux-next-history-e03f0b53b4bd51b70e48e3548bd1163e8496ff9e.tar.gz | |
Revert "vsock/virtio: fix skb overhead overflow on 32-bit builds"
This reverts commit 4157501b9a8f ("vsock/virtio: fix skb overhead
overflow on 32-bit builds"). The fix was semantically correct (although
it would have been better to use mul_u32_u32(), as David pointed out),
but in practice we are estimating the memory used to allocate the SKBs,
and this will never cause a 32-bit variable to overflow on a 32-bit
system, since the memory would have run out long before that. On 64-bit,
SKB_TRUESIZE() already evaluates to size_t, so the multiplication is
already in 64-bit arithmetic without the cast.
Let's revert this to avoid unnecessary 64-bit multiplies on the
per-packet receive path on 32-bit systems.
Reported-by: David Laight <david.laight.linux@gmail.com>
Closes: https://lore.kernel.org/netdev/20260523173557.5cc4f4f6@pumpkin
Suggested-by: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Laight <david.laight.linux@gmail.com>
Link: https://patch.msgid.link/20260527171046.130211-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/vmw_vsock/virtio_transport_common.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index b143290a311d1..d4d26fba9e372 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -417,7 +417,7 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk, static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs, u32 len) { - u64 skb_overhead = ((u64)skb_queue_len(&vvs->rx_queue) + 1) * SKB_TRUESIZE(0); + u64 skb_overhead = (skb_queue_len(&vvs->rx_queue) + 1) * SKB_TRUESIZE(0); /* Allow at most buf_alloc * 2 total budget (payload + overhead), * similar to how SO_RCVBUF is doubled to reserve space for sk_buff |