github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-12 16:18:45 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

selftests/bpf: Test TCP_NODELAY in TCP hdr opt callbacks

Browse Source 
Add a sockops selftest for the TCP_NODELAY restriction in
BPF_SOCK_OPS_HDR_OPT_LEN_CB and BPF_SOCK_OPS_WRITE_HDR_OPT_CB.

With BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG enabled,
bpf_setsockopt(TCP_NODELAY) returns -EOPNOTSUPP from
BPF_SOCK_OPS_HDR_OPT_LEN_CB and BPF_SOCK_OPS_WRITE_HDR_OPT_CB, avoiding
unbounded recursion and kernel stack overflow.

Other cases continue to work as before, including
BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB.

Signed-off-by: KaFai Wan <kafai.wan@linux.dev>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260421155804.135786-4-kafai.wan@linux.dev
This commit is contained in:
KaFai Wan 2026-04-21 23:58:03 +08:00 committed by Martin KaFai Lau
parent 54377fcab5
commit 52b6b53349
2 changed files with 18 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
tools/testing/selftests/bpf/prog_tests/tcp_hdr_options.c
View File

@ -507,6 +507,10 @@ static void misc(void)
ASSERT_EQ(misc_skel->bss->nr_hwtstamp, 0, "nr_hwtstamp");
ASSERT_TRUE(misc_skel->bss->nodelay_est_ok, "nodelay_est_ok");
ASSERT_TRUE(misc_skel->bss->nodelay_hdr_len_reject, "nodelay_hdr_len_reject");
ASSERT_TRUE(misc_skel->bss->nodelay_write_hdr_reject, "nodelay_write_hdr_reject");
check_linum:
ASSERT_FALSE(check_error_linum(&sk_fds), "check_error_linum");
sk_fds_close(&sk_fds);

15
tools/testing/selftests/bpf/progs/test_misc_tcp_hdr_options.c
View File

@ -29,6 +29,10 @@ unsigned int nr_syn = 0;
unsigned int nr_fin = 0;
unsigned int nr_hwtstamp = 0;
bool nodelay_est_ok = false;
bool nodelay_hdr_len_reject = false;
bool nodelay_write_hdr_reject = false;
/* Check the header received from the active side */
static int __check_active_hdr_in(struct bpf_sock_ops *skops, bool check_syn)
{
@ -300,7 +304,7 @@ static int handle_passive_estab(struct bpf_sock_ops *skops)
SEC("sockops")
int misc_estab(struct bpf_sock_ops *skops)
{
int true_val = 1;
int true_val = 1, false_val = 0, ret;
switch (skops->op) {
case BPF_SOCK_OPS_TCP_LISTEN_CB:
@ -316,10 +320,19 @@ int misc_estab(struct bpf_sock_ops *skops)
case BPF_SOCK_OPS_PARSE_HDR_OPT_CB:
return handle_parse_hdr(skops);
case BPF_SOCK_OPS_HDR_OPT_LEN_CB:
ret = bpf_setsockopt(skops, SOL_TCP, TCP_NODELAY, &true_val, sizeof(true_val));
if (ret == -EOPNOTSUPP)
nodelay_hdr_len_reject = true;
return handle_hdr_opt_len(skops);
case BPF_SOCK_OPS_WRITE_HDR_OPT_CB:
ret = bpf_setsockopt(skops, SOL_TCP, TCP_NODELAY, &true_val, sizeof(true_val));
if (ret == -EOPNOTSUPP)
nodelay_write_hdr_reject = true;
return handle_write_hdr_opt(skops);
case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
ret = bpf_setsockopt(skops, SOL_TCP, TCP_NODELAY, &false_val, sizeof(false_val));
if (!ret)
nodelay_est_ok = true;
return handle_passive_estab(skops);
}