Update filter_udphdr to use bpf_dynptr_slice to read the packet headers instead of accessing them directly.
The function previously returned a pointer to the UDP header, which was then used to calculate Ethernet and IP header lengths by subtracting xdp->data. Since this only works when the UDP header is in the linear region, rework the function to return the total header length instead of a pointer. Rename filter_udphdr() to check_udphdr() to reflect the new behavior.
This makes the test viable for drivers that do not store any packet data in the linear part when in multi-buffer mode.
Signed-off-by: Nimrod Oren noren@nvidia.com Reviewed-by: Carolina Jubran cjubran@nvidia.com Reviewed-by: Dragos Tatulea dtatulea@nvidia.com --- .../selftests/net/lib/xdp_native.bpf.c | 80 +++++++------------ 1 file changed, 31 insertions(+), 49 deletions(-)
diff --git a/tools/testing/selftests/net/lib/xdp_native.bpf.c b/tools/testing/selftests/net/lib/xdp_native.bpf.c index ff63f572552b..6df5164e3791 100644 --- a/tools/testing/selftests/net/lib/xdp_native.bpf.c +++ b/tools/testing/selftests/net/lib/xdp_native.bpf.c @@ -63,53 +63,49 @@ static void record_stats(struct xdp_md *ctx, __u32 stat_type) __sync_fetch_and_add(count, 1); }
-static struct udphdr *filter_udphdr(struct xdp_md *ctx, __u16 port) +static __u32 check_udphdr(struct xdp_md *ctx, __u16 port) { - void *data_end = (void *)(long)ctx->data_end; - void *data = (void *)(long)ctx->data; struct udphdr *udph = NULL; - struct ethhdr *eth = data; + struct ethhdr *eth = NULL; + struct bpf_dynptr ptr;
- if (data + sizeof(*eth) > data_end) - return NULL; + bpf_dynptr_from_xdp(ctx, 0, &ptr); + eth = bpf_dynptr_slice(&ptr, 0, NULL, sizeof(*eth)); + if (!eth) + return 0;
if (eth->h_proto == bpf_htons(ETH_P_IP)) { - struct iphdr *iph = data + sizeof(*eth); + struct iphdr *iph = bpf_dynptr_slice(&ptr, sizeof(*eth), + NULL, sizeof(*iph));
- if (iph + 1 > (struct iphdr *)data_end || - iph->protocol != IPPROTO_UDP) - return NULL; + if (!iph || iph->protocol != IPPROTO_UDP) + return 0;
- udph = (void *)eth + sizeof(*iph) + sizeof(*eth); - } else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) { - struct ipv6hdr *ipv6h = data + sizeof(*eth); + udph = bpf_dynptr_slice(&ptr, sizeof(*iph) + sizeof(*eth), + NULL, sizeof(*udph)); + } else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) { + struct ipv6hdr *ipv6h = bpf_dynptr_slice(&ptr, sizeof(*eth), + NULL, sizeof(*ipv6h));
- if (ipv6h + 1 > (struct ipv6hdr *)data_end || - ipv6h->nexthdr != IPPROTO_UDP) - return NULL; + if (!ipv6h || ipv6h->nexthdr != IPPROTO_UDP) + return 0;
- udph = (void *)eth + sizeof(*ipv6h) + sizeof(*eth); + udph = bpf_dynptr_slice(&ptr, sizeof(*ipv6h) + sizeof(*eth), + NULL, sizeof(*udph)); } else { - return NULL; + return 0; }
- if (udph + 1 > (struct udphdr *)data_end) - return NULL; - - if (udph->dest != bpf_htons(port)) - return NULL; + if (!udph || udph->dest != bpf_htons(port)) + return 0;
record_stats(ctx, STATS_RX); - - return udph; + return (void *)udph - (void *)eth + sizeof(*udph); }
static int xdp_mode_pass(struct xdp_md *ctx, __u16 port) { - struct udphdr *udph = NULL; - - udph = filter_udphdr(ctx, port); - if (!udph) + if (!check_udphdr(ctx, port)) return XDP_PASS;
record_stats(ctx, STATS_PASS); @@ -119,10 +115,7 @@ static int xdp_mode_pass(struct xdp_md *ctx, __u16 port)
static int xdp_mode_drop_handler(struct xdp_md *ctx, __u16 port) { - struct udphdr *udph = NULL; - - udph = filter_udphdr(ctx, port); - if (!udph) + if (!check_udphdr(ctx, port)) return XDP_PASS;
record_stats(ctx, STATS_DROP); @@ -363,19 +356,14 @@ static int xdp_adjst_tail_grow_data(struct xdp_md *ctx, __u16 offset)
static int xdp_adjst_tail(struct xdp_md *ctx, __u16 port) { - void *data = (void *)(long)ctx->data; - struct udphdr *udph = NULL; - __s32 *adjust_offset, *val; + __s32 *adjust_offset; __u32 key, hdr_len; - void *offset_ptr; - __u8 tag; int ret;
- udph = filter_udphdr(ctx, port); - if (!udph) + hdr_len = check_udphdr(ctx, port); + if (!hdr_len) return XDP_PASS;
- hdr_len = (void *)udph - data + sizeof(struct udphdr); key = XDP_ADJST_OFFSET; adjust_offset = bpf_map_lookup_elem(&map_xdp_setup, &key); if (!adjust_offset) @@ -504,20 +492,14 @@ static int xdp_adjst_head_grow_data(struct xdp_md *ctx, __u64 hdr_len,
static int xdp_head_adjst(struct xdp_md *ctx, __u16 port) { - void *data_end = (void *)(long)ctx->data_end; - void *data = (void *)(long)ctx->data; - struct udphdr *udph_ptr = NULL; __u32 key, size, hdr_len; __s32 *val; int res;
- /* Filter packets based on UDP port */ - udph_ptr = filter_udphdr(ctx, port); - if (!udph_ptr) + hdr_len = check_udphdr(ctx, port); + if (!hdr_len) return XDP_PASS;
- hdr_len = (void *)udph_ptr - data + sizeof(struct udphdr); - key = XDP_ADJST_OFFSET; val = bpf_map_lookup_elem(&map_xdp_setup, &key); if (!val)