diff options
| author | Maciej Fijalkowski <maciej.fijalkowski@intel.com> | 2026-04-02 17:49:51 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-04-06 18:43:51 -0700 |
| commit | a315e022a72d95ef5f1d4e58e903cb492b0ad931 (patch) | |
| tree | 2635b4d006440efe428dab4bb14008bbb6daea23 | |
| parent | 1caa871bb0615e2b68aa11bb7b453eeac770ea1d (diff) | |
xsk: tighten UMEM headroom validation to account for tailroom and min frame
The current headroom validation in xdp_umem_reg() could leave us with
insufficient space dedicated to even receive minimum-sized ethernet
frame. Furthermore if multi-buffer would come to play then
skb_shared_info stored at the end of XSK frame would be corrupted.
HW typically works with 128-aligned sizes so let us provide this value
as bare minimum.
Multi-buffer setting is known later in the configuration process so
besides accounting for 128 bytes, let us also take care of tailroom space
upfront.
Reviewed-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Fixes: 99e3a236dd43 ("xsk: Add missing check on user supplied headroom size")
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://patch.msgid.link/20260402154958.562179-2-maciej.fijalkowski@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/xdp/xdp_umem.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index 066ce07c506d..58da2f4f4397 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -203,7 +203,8 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr) if (!unaligned_chunks && chunks_rem) return -EINVAL; - if (headroom >= chunk_size - XDP_PACKET_HEADROOM) + if (headroom > chunk_size - XDP_PACKET_HEADROOM - + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) - 128) return -EINVAL; if (mr->flags & XDP_UMEM_TX_METADATA_LEN) { |