This needs two new helpers, one that works in a sleepable context (using
sock_gen_cookie which disables/enables preemption) and one that does not
(for performance reasons). Both take a struct sock pointer and need to
check it for NULLness.
This helper could also be useful to other BPF program types such as LSM.
Signed-off-by: Florent Revest <rev...@chromium.org>
---
include/linux/bpf.h | 1 +
include/uapi/linux/bpf.h | 7 +++++++
kernel/trace/bpf_trace.c | 2 ++
net/core/filter.c | 12 ++++++++++++
tools/include/uapi/linux/bpf.h | 7 +++++++
5 files changed, 29 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 07cb5d15e743..5a858e8c3f1a 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1860,6 +1860,7 @@ extern const struct bpf_func_proto bpf_per_cpu_ptr_proto;
extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;
extern const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto;
extern const struct bpf_func_proto bpf_sock_from_file_proto;
+extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto;
const struct bpf_func_proto *bpf_tracing_func_proto(
enum bpf_func_id func_id, const struct bpf_prog *prog);
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index ba59309f4d18..9ac66cf25959 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1667,6 +1667,13 @@ union bpf_attr {
* Return
* A 8-byte long unique number.
*
+ * u64 bpf_get_socket_cookie(void *sk)
+ * Description
+ * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
+ * *sk*, but gets socket from a BTF **struct sock**.
+ * Return
+ * A 8-byte long unique number.
+ *
* u32 bpf_get_socket_uid(struct sk_buff *skb)
* Return
* The owner UID of the socket associated to *skb*. If the socket
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 52ddd217d6a1..be5e96de306d 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1760,6 +1760,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const
struct bpf_prog *prog)
return &bpf_sk_storage_delete_tracing_proto;
case BPF_FUNC_sock_from_file:
return &bpf_sock_from_file_proto;
+ case BPF_FUNC_get_socket_cookie:
+ return &bpf_get_socket_ptr_cookie_proto;
#endif
case BPF_FUNC_seq_printf:
return prog->expected_attach_type == BPF_TRACE_ITER ?
diff --git a/net/core/filter.c b/net/core/filter.c
index 255aeee72402..13ad9a64f04f 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4631,6 +4631,18 @@ static const struct bpf_func_proto
bpf_get_socket_cookie_sock_proto = {
.arg1_type = ARG_PTR_TO_CTX,
};
+BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
+{
+ return sk ? sock_gen_cookie(sk) : 0;
+}
+
+const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
+ .func = bpf_get_socket_ptr_cookie,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
+};
+
BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
{
return __sock_gen_cookie(ctx->sk);
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index ba59309f4d18..9ac66cf25959 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1667,6 +1667,13 @@ union bpf_attr {
* Return
* A 8-byte long unique number.
*
+ * u64 bpf_get_socket_cookie(void *sk)
+ * Description
+ * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
+ * *sk*, but gets socket from a BTF **struct sock**.
+ * Return
+ * A 8-byte long unique number.
+ *
* u32 bpf_get_socket_uid(struct sk_buff *skb)
* Return
* The owner UID of the socket associated to *skb*. If the socket
--
2.29.2.576.ga3fc446d84-goog
