The intention of the current check is to avoid using bpf_sk_storage
in irq and nmi. Jakub pointed out that the current check cannot
do that. For example, in_serving_softirq() returns true
if the softirq handling is interrupted by hard irq.
Fixes: 8e4597c627fb ("bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP")
Suggested-by: Jakub Kicinski <[email protected]>
Signed-off-by: Martin KaFai Lau <[email protected]>
---
net/core/bpf_sk_storage.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index 359908a7d3c1..a32037daa933 100644
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -415,7 +415,7 @@ static bool bpf_sk_storage_tracing_allowed(const struct
bpf_prog *prog)
BPF_CALL_4(bpf_sk_storage_get_tracing, struct bpf_map *, map, struct sock *,
sk,
void *, value, u64, flags)
{
- if (!in_serving_softirq() && !in_task())
+ if (in_irq() || in_nmi())
return (unsigned long)NULL;
return (unsigned long)____bpf_sk_storage_get(map, sk, value, flags);
@@ -424,7 +424,7 @@ BPF_CALL_4(bpf_sk_storage_get_tracing, struct bpf_map *,
map, struct sock *, sk,
BPF_CALL_2(bpf_sk_storage_delete_tracing, struct bpf_map *, map,
struct sock *, sk)
{
- if (!in_serving_softirq() && !in_task())
+ if (in_irq() || in_nmi())
return -EPERM;
return ____bpf_sk_storage_delete(map, sk);
--
2.24.1
