check_helper_call() prints the error message for every env->cur_state->active* element when calling a sleepable helper. Consolidate all of them into a single print statement. The check for env->cur_state->active_locks was not part of the removed print statements and will not be triggered with the consolidated print as well because it is checked in do_check() before check_helper_call() is even reached. Signed-off-by: Puranjay Mohan Acked-by: Mykyta Yatsenko --- kernel/bpf/verifier.c | 44 +++++++------------ .../selftests/bpf/prog_tests/summarization.c | 2 +- .../bpf/progs/verifier_async_cb_context.c | 4 +- 3 files changed, 20 insertions(+), 30 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index c80e96c2c271..1d7f1b5c439a 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -11593,6 +11593,19 @@ static inline bool in_sleepable_context(struct bpf_verifier_env *env) in_sleepable(env); } +static const char *non_sleepable_context_description(struct bpf_verifier_env *env) +{ + if (env->cur_state->active_rcu_locks) + return "rcu_read_lock region"; + if (env->cur_state->active_preempt_locks) + return "non-preemptible region"; + if (env->cur_state->active_irq_id) + return "IRQ-disabled region"; + if (env->cur_state->active_locks) + return "lock region"; + return "non-sleepable prog"; +} + static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn, int *insn_idx_p) { @@ -11632,11 +11645,6 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return -EINVAL; } - if (!in_sleepable(env) && fn->might_sleep) { - verbose(env, "helper call might sleep in a non-sleepable prog\n"); - return -EINVAL; - } - /* With LD_ABS/IND some JITs save/restore skb from r1. */ changes_data = bpf_helper_changes_pkt_data(func_id); if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) { @@ -11653,28 +11661,10 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return err; } - if (env->cur_state->active_rcu_locks) { - if (fn->might_sleep) { - verbose(env, "sleepable helper %s#%d in rcu_read_lock region\n", - func_id_name(func_id), func_id); - return -EINVAL; - } - } - - if (env->cur_state->active_preempt_locks) { - if (fn->might_sleep) { - verbose(env, "sleepable helper %s#%d in non-preemptible region\n", - func_id_name(func_id), func_id); - return -EINVAL; - } - } - - if (env->cur_state->active_irq_id) { - if (fn->might_sleep) { - verbose(env, "sleepable helper %s#%d in IRQ-disabled region\n", - func_id_name(func_id), func_id); - return -EINVAL; - } + if (fn->might_sleep && !in_sleepable_context(env)) { + verbose(env, "sleepable helper %s#%d in %s\n", func_id_name(func_id), func_id, + non_sleepable_context_description(env)); + return -EINVAL; } /* Track non-sleepable context for helpers. */ diff --git a/tools/testing/selftests/bpf/prog_tests/summarization.c b/tools/testing/selftests/bpf/prog_tests/summarization.c index 5dd6c120a838..6951786044ca 100644 --- a/tools/testing/selftests/bpf/prog_tests/summarization.c +++ b/tools/testing/selftests/bpf/prog_tests/summarization.c @@ -58,7 +58,7 @@ static void test_aux(const char *main_prog_name, * this particular combination can be enabled. */ if (!strcmp("might_sleep", replacement) && err) { - ASSERT_HAS_SUBSTR(log, "helper call might sleep in a non-sleepable prog", "error log"); + ASSERT_HAS_SUBSTR(log, "sleepable helper bpf_copy_from_user#", "error log"); ASSERT_EQ(err, -EINVAL, "err"); test__skip(); goto out; diff --git a/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c b/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c index 39aff82549c9..6bf95550a024 100644 --- a/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c +++ b/tools/testing/selftests/bpf/progs/verifier_async_cb_context.c @@ -31,7 +31,7 @@ static int timer_cb(void *map, int *key, struct bpf_timer *timer) } SEC("fentry/bpf_fentry_test1") -__failure __msg("helper call might sleep in a non-sleepable prog") +__failure __msg("sleepable helper bpf_copy_from_user#{{[0-9]+}} in non-sleepable prog") int timer_non_sleepable_prog(void *ctx) { struct timer_elem *val; @@ -47,7 +47,7 @@ int timer_non_sleepable_prog(void *ctx) } SEC("lsm.s/file_open") -__failure __msg("helper call might sleep in a non-sleepable prog") +__failure __msg("sleepable helper bpf_copy_from_user#{{[0-9]+}} in non-sleepable prog") int timer_sleepable_prog(void *ctx) { struct timer_elem *val; -- 2.47.3