bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb

bpf_prog_test_run_skb() calls eth_type_trans() first and then uses
skb->protocol to initialize sk family and address fields for the test
run.

For IPv4 and IPv6 packets, it may access ip_hdr(skb) or ipv6_hdr(skb)
even when the provided test input only contains an Ethernet header.

Reject the input earlier if the Ethernet frame carries IPv4/IPv6
EtherType but the L3 header is too short.

Fold the IPv4/IPv6 header length checks into the existing protocol
switch and return -EINVAL before accessing the network headers.

Fixes: fa5cb548ced6 ("bpf: Setup socket family and addresses in bpf_prog_test_run_skb")
Reported-by: syzbot+619b9ef527f510a57cfc@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=619b9ef527f510a57cfc
Signed-off-by: Sun Jian <sun.jian.kdev@gmail.com>
Link: https://lore.kernel.org/r/20260408034623.180320-2-sun.jian.kdev@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

0 files changed, 0 insertions, 0 deletions