[PATCH 7.1 072/271] xsk: require at least 16 bytes of TX metadata
Greg Kroah-Hartman <[email protected]>
| Newsgroups | dev.linux.lists.patches,org.kernel.vger.stable |
|---|---|
| Message-ID | <[email protected]> |
7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanislav Fomichev <[email protected]> [ Upstream commit 1bb30b181d9f0484e141f8411e15ed906d5c6780 ] AF_XDP accepts a TX metadata length as small as eight bytes, but every supported request needs the flags plus at least one eight-byte request field. Such short metadata also lets the kernel read beyond the registered area. Require 16 bytes rather than sizeof(struct xsk_tx_metadata) to preserve compatibility with applications that do not use launch-time metadata. Fixes: 341ac980eab9 ("xsk: Support tx_metadata_len") Reported-by: [email protected] Reported-by: Cen Zhang (Microsoft) <[email protected]> Link: https://lore.kernel.org/netdev/[email protected]/ Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- net/xdp/xdp_umem.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index 58da2f4f4397a..cd8643360eb3a 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -210,6 +210,8 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr) if (mr->flags & XDP_UMEM_TX_METADATA_LEN) { if (mr->tx_metadata_len >= 256 || mr->tx_metadata_len % 8) return -EINVAL; + if (mr->tx_metadata_len < 16) + return -EINVAL; umem->tx_metadata_len = mr->tx_metadata_len; } -- 2.53.0