This patch adds a test to ensure bpf_setsockopt(TCP_CONGESTION, "not_exist") will not trigger the kernel module autoload. Before the fix: [ 40.535829] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274 ... [ 40.552134] tcp_ca_find_autoload.constprop.0+0xcb/0x200 [ 40.552689] tcp_set_congestion_control+0x99/0x7b0 [ 40.553203] do_tcp_setsockopt+0x3ed/0x2240 ... [ 40.556041] __bpf_setsockopt+0x124/0x640 Signed-off-by: Martin KaFai Lau <martin.lau@xxxxxxxxx> --- tools/testing/selftests/bpf/progs/setget_sockopt.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/testing/selftests/bpf/progs/setget_sockopt.c b/tools/testing/selftests/bpf/progs/setget_sockopt.c index 40606ef47a38..79debf3c2f44 100644 --- a/tools/testing/selftests/bpf/progs/setget_sockopt.c +++ b/tools/testing/selftests/bpf/progs/setget_sockopt.c @@ -32,6 +32,7 @@ struct sockopt_test { unsigned int flip:1; }; +static const char not_exist_cc[] = "not_exist"; static const char cubic_cc[] = "cubic"; static const char reno_cc[] = "reno"; @@ -307,6 +308,9 @@ static int bpf_test_tcp_sockopt(__u32 i, struct loop_ctx *lc) const char *new_cc; int new_cc_len; + if (!bpf_setsockopt(ctx, IPPROTO_TCP, TCP_CONGESTION, + (void *)not_exist_cc, sizeof(not_exist_cc))) + return 1; if (bpf_getsockopt(ctx, IPPROTO_TCP, TCP_CONGESTION, old_cc, sizeof(old_cc))) return 1; if (!bpf_strncmp(old_cc, sizeof(old_cc), cubic_cc)) { -- 2.30.2