Kernel/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2025-01-16 02:14:58 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

selftests/bpf: validate that tail call invalidates packet pointers

Browse Source 
Add a test case with a tail call done from a global sub-program. Such
tails calls should be considered as invalidating packet pointers.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20241210041100.1898468-9-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Eduard Zingerman 2024-12-09 20:11:00 -08:00 committed by Alexei Starovoitov
parent 1a4607ffba
commit d9706b56e1
1 changed files with 28 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
tools/testing/selftests/bpf/progs/verifier_sock.c
View File

@ -50,6 +50,13 @@ struct {
__uint(map_flags, BPF_F_NO_PREALLOC);
} sk_storage_map SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 1);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} jmp_table SEC(".maps");
SEC("cgroup/skb")
__description("skb->sk: no NULL check")
__failure __msg("invalid mem access 'sock_common_or_null'")
@ -1065,4 +1072,25 @@ int invalidate_pkt_pointers_from_global_func(struct __sk_buff *sk)
return TCX_PASS;
}
__noinline
int tail_call(struct __sk_buff *sk)
{
bpf_tail_call_static(sk, &jmp_table, 0);
return 0;
}
/* Tail calls invalidate packet pointers. */
SEC("tc")
__failure __msg("invalid mem access")
int invalidate_pkt_pointers_by_tail_call(struct __sk_buff *sk)
{
int *p = (void *)(long)sk->data;
if ((void *)(p + 1) > (void *)(long)sk->data_end)
return TCX_DROP;
tail_call(sk);
*p = 42; /* this is unsafe */
return TCX_PASS;
}
char _license[] SEC("license") = "GPL";