bpf: Add function for XDP meta data length check

This commit prepares to use the XDP meta data length check in multiple
places by making it into a static inline function instead of a literal.

Co-developed-by: Cody Haas <chaas@riotgames.com>
Co-developed-by: Lisa Watanabe <lwatanabe@riotgames.com>
Signed-off-by: Cody Haas <chaas@riotgames.com>
Signed-off-by: Lisa Watanabe <lwatanabe@riotgames.com>
Signed-off-by: Zvi Effron <zeffron@riotgames.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210707221657.3985075-2-zeffron@riotgames.com
This commit is contained in:
Zvi Effron 2021-07-07 22:16:54 +00:00 committed by Alexei Starovoitov
parent 5e437416ff
commit 7445cf31d2
2 changed files with 7 additions and 2 deletions

View File

@ -276,6 +276,11 @@ xdp_data_meta_unsupported(const struct xdp_buff *xdp)
return unlikely(xdp->data_meta > xdp->data);
}
static inline bool xdp_metalen_invalid(unsigned long metalen)
{
return (metalen & (sizeof(__u32) - 1)) || (metalen > 32);
}
struct xdp_attachment_info {
struct bpf_prog *prog;
u32 flags;

View File

@ -77,6 +77,7 @@
#include <net/transp_v6.h>
#include <linux/btf_ids.h>
#include <net/tls.h>
#include <net/xdp.h>
static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id);
@ -3880,8 +3881,7 @@ BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
if (unlikely(meta < xdp_frame_end ||
meta > xdp->data))
return -EINVAL;
if (unlikely((metalen & (sizeof(__u32) - 1)) ||
(metalen > 32)))
if (unlikely(xdp_metalen_invalid(metalen)))
return -EACCES;
xdp->data_meta = meta;