From: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> [ Upstream commit 60548b825b082cedf89b275c21c28b1e1d030e50 ] Default samples/pktgen scripts send 60 byte packets as hardware adds 4-bytes FCS checksum, which fulfils minimum Ethernet 64 bytes frame size. XDP layer will not necessary have access to the 4-bytes FCS checksum. This leads to bpf_xdp_load_bytes() failing as it tries to copy 64-bytes from an XDP packet that only have 60-bytes available. Fixes: 772251742262 ("samples/bpf: fixup some tools to be able to support xdp multibuffer") Signed-off-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxx> Link: https://lore.kernel.org/bpf/168545704139.2996228.2516528552939485216.stgit@firesoul Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- samples/bpf/xdp1_kern.c | 2 +- samples/bpf/xdp2_kern.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/samples/bpf/xdp1_kern.c b/samples/bpf/xdp1_kern.c index 0a5c704badd00..d91f27cbcfa99 100644 --- a/samples/bpf/xdp1_kern.c +++ b/samples/bpf/xdp1_kern.c @@ -39,7 +39,7 @@ static int parse_ipv6(void *data, u64 nh_off, void *data_end) return ip6h->nexthdr; } -#define XDPBUFSIZE 64 +#define XDPBUFSIZE 60 SEC("xdp.frags") int xdp_prog1(struct xdp_md *ctx) { diff --git a/samples/bpf/xdp2_kern.c b/samples/bpf/xdp2_kern.c index 67804ecf7ce37..8bca674451ed1 100644 --- a/samples/bpf/xdp2_kern.c +++ b/samples/bpf/xdp2_kern.c @@ -55,7 +55,7 @@ static int parse_ipv6(void *data, u64 nh_off, void *data_end) return ip6h->nexthdr; } -#define XDPBUFSIZE 64 +#define XDPBUFSIZE 60 SEC("xdp.frags") int xdp_prog1(struct xdp_md *ctx) { -- 2.39.2