From 824adae4530b4db1d06987d8dd31a0adef37044f Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Mon, 17 Jul 2023 21:45:30 +0530 Subject: selftests/bpf: Add more tests for check_max_stack_depth bug Another test which now exercies the path of the verifier where it will explore call chains rooted at the async callback. Without the prior fixes, this program loads successfully, which is incorrect. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20230717161530.1238-4-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- .../selftests/bpf/progs/async_stack_depth.c | 25 ++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) (limited to 'tools/testing') diff --git a/tools/testing/selftests/bpf/progs/async_stack_depth.c b/tools/testing/selftests/bpf/progs/async_stack_depth.c index 477ba950bb43..3517c0e01206 100644 --- a/tools/testing/selftests/bpf/progs/async_stack_depth.c +++ b/tools/testing/selftests/bpf/progs/async_stack_depth.c @@ -22,9 +22,16 @@ static int timer_cb(void *map, int *key, struct bpf_timer *timer) return buf[69]; } +__attribute__((noinline)) +static int bad_timer_cb(void *map, int *key, struct bpf_timer *timer) +{ + volatile char buf[300] = {}; + return buf[255] + timer_cb(NULL, NULL, NULL); +} + SEC("tc") -__failure __msg("combined stack size of 2 calls") -int prog(struct __sk_buff *ctx) +__failure __msg("combined stack size of 2 calls is 576. Too large") +int pseudo_call_check(struct __sk_buff *ctx) { struct hmap_elem *elem; volatile char buf[256] = {}; @@ -37,4 +44,18 @@ int prog(struct __sk_buff *ctx) return bpf_timer_set_callback(&elem->timer, timer_cb) + buf[0]; } +SEC("tc") +__failure __msg("combined stack size of 2 calls is 608. Too large") +int async_call_root_check(struct __sk_buff *ctx) +{ + struct hmap_elem *elem; + volatile char buf[256] = {}; + + elem = bpf_map_lookup_elem(&hmap, &(int){0}); + if (!elem) + return 0; + + return bpf_timer_set_callback(&elem->timer, bad_timer_cb) + buf[0]; +} + char _license[] SEC("license") = "GPL"; -- cgit v1.2.3