[PATCH bpf v2 04/11] selftests/bpf: Add selftests for rx_queue_mapping context access
COOLING12d
From: Emil Tsalapatis <emil@etsalapatis.com>
Date: 2026-09-22 17:20:45
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Shuah Khan, Linus Torvalds
Revision v2 of 2 in this series.
Revisions (2)
- v1 [diff vs current]
- v2 current
Add tests to ensure the verifier properly tracks the 0 bit state and width of the rx_queue_mapping field read from struct sock. Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com> --- .../selftests/bpf/progs/verifier_sock.c | 38 +++++++++++++++++++ 1 file changed, 38 insertions(+)
diff --git a/tools/testing/selftests/bpf/progs/verifier_sock.c b/tools/testing/selftests/bpf/progs/verifier_sock.c
index 2a136c917..565c4d8bc 100644
--- a/tools/testing/selftests/bpf/progs/verifier_sock.c
+++ b/tools/testing/selftests/bpf/progs/verifier_sock.c@@ -88,6 +88,44 @@ l0_%=: r0 = *(u32*)(r1 + %[bpf_sock_family]); \ : __clobber_all); } +SEC("socket") +__description("skb->sk: sk->rx_queue_mapping [no sign extension]") +__success __success_unpriv __retval(0) +__naked void sk_rx_queue_mapping_no_sign_ext(void) +{ + asm volatile (" \ + r1 = *(u64*)(r1 + %[__sk_buff_sk]); \ + if r1 != 0 goto l0_%=; \ + r0 = 0xdead; \ + exit; \ +l0_%=: r0 = *(u32*)(r1 + %[bpf_sock_rx_queue_mapping]); \ + r0 >>= 32; \ + exit; \ +" : + : __imm_const(__sk_buff_sk, offsetof(struct __sk_buff, sk)), + __imm_const(bpf_sock_rx_queue_mapping, offsetof(struct bpf_sock, rx_queue_mapping)) + : __clobber_all); +} + +SEC("socket") +__description("skb->sk: sk->rx_queue_mapping [narrow load mask]") +__success __success_unpriv __retval(0) +__naked void sk_rx_queue_mapping_narrow_load_mask(void) +{ + asm volatile (" \ + r1 = *(u64*)(r1 + %[__sk_buff_sk]); \ + if r1 != 0 goto l0_%=; \ + r0 = 0xdead; \ + exit; \ +l0_%=: r0 = *(u16*)(r1 + %[bpf_sock_rx_queue_mapping]); \ + r0 >>= 16; \ + exit; \ +" : + : __imm_const(__sk_buff_sk, offsetof(struct __sk_buff, sk)), + __imm_const(bpf_sock_rx_queue_mapping, offsetof(struct bpf_sock, rx_queue_mapping)) + : __clobber_all); +} + SEC("cgroup/skb") __description("skb->sk: sk->type [fullsock field]") __failure __msg("invalid sock_common access")
--
2.54.0