Re: [PATCH net-next v4 0/9] tun: Unify vnet implementation
From: Willem de Bruijn
Date: Mon Jan 20 2025 - 06:07:51 EST
Akihiko Odaki wrote:
> When I implemented virtio's hash-related features to tun/tap [1],
> I found tun/tap does not fill the entire region reserved for the virtio
> header, leaving some uninitialized hole in the middle of the buffer
> after read()/recvmesg().
>
> This series fills the uninitialized hole. More concretely, the
> num_buffers field will be initialized with 1, and the other fields will
> be inialized with 0. Setting the num_buffers field to 1 is mandated by
> virtio 1.0 [2].
>
> The change to virtio header is preceded by another change that refactors
> tun and tap to unify their virtio-related code.
>
> [1]: https://lore.kernel.org/r/20241008-rss-v5-0-f3cf68df005d@xxxxxxxxxx
> [2]: https://lore.kernel.org/r/20241227084256-mutt-send-email-mst@xxxxxxxxxx/
>
> Signed-off-by: Akihiko Odaki <akihiko.odaki@xxxxxxxxxx>
net-next is closed. But I'll review for when you resend.
> ---
> Changes in v4:
> - s/sz/vnet_hdr_len_sz/ for patch "tun: Decouple vnet handling"
> (Willem de Bruijn)
Minor, and sorry my bad: len_sz is duplicative, vnet_hdr_sz is common.
> - Reverted to add CONFIG_TUN_VNET.
> - Link to v3: https://lore.kernel.org/r/20250116-tun-v3-0-c6b2871e97f7@xxxxxxxxxx
>
> Changes in v3:
> - Dropped changes to fill the vnet header.
> - Splitted patch "tun: Unify vnet implementation".
> - Reverted spurious changes in patch "tun: Unify vnet implementation".
> - Merged tun_vnet.c into TAP.
> - Link to v2: https://lore.kernel.org/r/20250109-tun-v2-0-388d7d5a287a@xxxxxxxxxx
>
> Changes in v2:
> - Fixed num_buffers endian.
> - Link to v1: https://lore.kernel.org/r/20250108-tun-v1-0-67d784b34374@xxxxxxxxxx
>
> ---
> Akihiko Odaki (9):
> tun: Refactor CONFIG_TUN_VNET_CROSS_LE
> tun: Avoid double-tracking iov_iter length changes
> tun: Keep hdr_len in tun_get_user()
> tun: Decouple vnet from tun_struct
> tun: Decouple vnet handling
> tun: Extract the vnet handling code
> tap: Avoid double-tracking iov_iter length changes
> tap: Keep hdr_len in tap_get_user()
> tap: Use tun's vnet-related code
>
> MAINTAINERS | 2 +-
> drivers/net/Kconfig | 5 ++
> drivers/net/Makefile | 1 +
> drivers/net/tap.c | 172 ++++++------------------------------------
> drivers/net/tun.c | 200 +++++++------------------------------------------
> drivers/net/tun_vnet.c | 184 +++++++++++++++++++++++++++++++++++++++++++++
> drivers/net/tun_vnet.h | 25 +++++++
> 7 files changed, 267 insertions(+), 322 deletions(-)
> ---
> base-commit: a32e14f8aef69b42826cf0998b068a43d486a9e9
> change-id: 20241230-tun-66e10a49b0c7
>
> Best regards,
> --
> Akihiko Odaki <akihiko.odaki@xxxxxxxxxx>
>