diff options
| author | Martin KaFai Lau <kafai@fb.com> | 2020-11-16 12:01:13 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-11-16 16:46:01 -0800 |
| commit | b93ef089d35c3386dd197e85afb6399bbd54cfb3 (patch) | |
| tree | 11b857e0b9e1c1e5ffb9cd4d8b467fd20d87ccd6 | |
| parent | 024cd2cbd1ca2d29e6df538855d52c4e5990cab7 (diff) | |
| download | linux-b93ef089d35c3386dd197e85afb6399bbd54cfb3.tar.bz2 | |
bpf: Fix the irq and nmi check in bpf_sk_storage for tracing usage
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 <kuba@kernel.org>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201116200113.2868539-1-kafai@fb.com
| -rw-r--r-- | net/core/bpf_sk_storage.c | 4 |
1 files 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); |