tetragon: probe_read usage may cause issues with newer kernels

Newer kernels should not use probe_read so convert to probe_read_kernel.
We have logic to rever to probe_read on older kernels when needed.

[Upstream commit: e27499d]

Signed-off-by: John Fastabend <john.fastabend@gmail.com>

bpf/include/api.h

@@ -267,6 +267,8 @@ static long BPF_FUNC(dynptr_read, void *dst, uint32_t len, const struct bpf_dynp
 static long BPF_FUNC(dynptr_write, const struct bpf_dynptr *dst, uint32_t offset, void *src, uint32_t len, uint64_t flags);
 static void BPF_FUNC(dynptr_data, const struct bpf_dynptr *ptr, uint32_t offset, uint32_t len);
 
+static long BPF_FUNC(sock_ops_cb_flags_set, struct bpf_sock_ops *bpf_sock, int argval);
+
 /** LLVM built-ins, mem*() routines work for constant size */
 
 #ifndef lock_xadd

bpf/lib/bpf_cgroup.h

@@ -108,7 +108,7 @@ FUNC_INLINE const char *__get_cgroup_kn_name(const struct kernfs_node *kn)
 	const char *name = NULL;
 
 	if (kn)
-		probe_read(&name, sizeof(name), _(&kn->name));
+		probe_read_kernel(&name, sizeof(name), _(&kn->name));
 
 	return name;
 }
@@ -137,7 +137,7 @@ FUNC_INLINE __u64 __get_cgroup_kn_id(const struct kernfs_node *kn)
 		if (BPF_CORE_READ_INTO(&id, old_kn, id.id) != 0)
 			return 0;
 	} else {
-		probe_read(&id, sizeof(id), _(&kn->id));
+		probe_read_kernel(&id, sizeof(id), _(&kn->id));
 	}
 
 	return id;
@@ -154,7 +154,7 @@ FUNC_INLINE struct kernfs_node *__get_cgroup_kn(const struct cgroup *cgrp)
 	struct kernfs_node *kn = NULL;
 
 	if (cgrp)
-		probe_read(&kn, sizeof(cgrp->kn), _(&cgrp->kn));
+		probe_read_kernel(&kn, sizeof(cgrp->kn), _(&cgrp->kn));
 
 	return kn;
 }
@@ -183,7 +183,7 @@ FUNC_INLINE __u32 get_cgroup_hierarchy_id(const struct cgroup *cgrp)
  * @cgrp: target cgroup
  *
  * Returns a pointer to the cgroup node name on success that can
- * be read with probe_read(). NULL on failures.
+ * be read with probe_read_kernel(). NULL on failures.
  */
 FUNC_INLINE const char *get_cgroup_name(const struct cgroup *cgrp)
 {
@@ -208,7 +208,7 @@ FUNC_INLINE __u32 get_cgroup_level(const struct cgroup *cgrp)
 {
 	__u32 level = 0;
 
-	probe_read(&level, sizeof(level), _(&cgrp->level));
+	probe_read_kernel(&level, sizeof(level), _(&cgrp->level));
 	return level;
 }
 
@@ -257,7 +257,7 @@ get_task_cgroup(struct task_struct *task, __u32 subsys_idx, __u32 *error_flags)
 	struct css_set *cgroups;
 	struct cgroup *cgrp = NULL;
 
-	probe_read(&cgroups, sizeof(cgroups), _(&task->cgroups));
+	probe_read_kernel(&cgroups, sizeof(cgroups), _(&task->cgroups));
 	if (unlikely(!cgroups)) {
 		*error_flags |= EVENT_ERROR_CGROUPS;
 		return cgrp;
@@ -290,13 +290,13 @@ get_task_cgroup(struct task_struct *task, __u32 subsys_idx, __u32 *error_flags)
 	 * support as much as workload as possible. It also reduces errors
 	 * in a significant way.
 	 */
-	probe_read(&subsys, sizeof(subsys), _(&cgroups->subsys[subsys_idx]));
+	probe_read_kernel(&subsys, sizeof(subsys), _(&cgroups->subsys[subsys_idx]));
 	if (unlikely(!subsys)) {
 		*error_flags |= EVENT_ERROR_CGROUP_SUBSYS;
 		return cgrp;
 	}
 
-	probe_read(&cgrp, sizeof(cgrp), _(&subsys->cgroup));
+	probe_read_kernel(&cgrp, sizeof(cgrp), _(&subsys->cgroup));
 	if (!cgrp)
 		*error_flags |= EVENT_ERROR_CGROUP_SUBSYSCGRP;
 

bpf/lib/bpf_task.h

@@ -26,7 +26,7 @@ FUNC_INLINE struct task_struct *get_parent(struct task_struct *t)
 	struct task_struct *task;
 
 	/* Read the real parent */
-	probe_read(&task, sizeof(task), _(&t->real_parent));
+	probe_read_kernel(&task, sizeof(task), _(&t->real_parent));
 	if (!task)
 		return 0;
 	return task;
@@ -45,7 +45,7 @@ FUNC_INLINE struct task_struct *get_task_from_pid(__u32 pid)
 			i = TASK_PID_LOOP;
 			continue;
 		}
-		probe_read(&cpid, sizeof(cpid), _(&task->tgid));
+		probe_read_kernel(&cpid, sizeof(cpid), _(&task->tgid));
 		if (cpid == pid) {
 			i = TASK_PID_LOOP;
 			continue;
@@ -68,7 +68,7 @@ FUNC_INLINE __u32 get_task_pid_vnr(void)
 
 	thread_pid_exists = bpf_core_field_exists(task->thread_pid);
 	if (thread_pid_exists) {
-		probe_read(&pid, sizeof(pid), _(&task->thread_pid));
+		probe_read_kernel(&pid, sizeof(pid), _(&task->thread_pid));
 		if (!pid)
 			return 0;
 	} else {
@@ -83,16 +83,16 @@ FUNC_INLINE __u32 get_task_pid_vnr(void)
 		if (!thread_pid_exists)
 			link_sz =
 				24; // voodoo magic, hard-code 24 to init stack
-		probe_read(&link, link_sz,
-			   (void *)_(&task->pids) + (PIDTYPE_PID * link_sz));
+		probe_read_kernel(&link, link_sz,
+				  (void *)_(&task->pids) + (PIDTYPE_PID * link_sz));
 		pid = link.pid;
 	}
 	upid_sz = bpf_core_field_size(pid->numbers[0]);
-	probe_read(&level, sizeof(level), _(&pid->level));
+	probe_read_kernel(&level, sizeof(level), _(&pid->level));
 	if (level < 1)
 		return 0;
-	probe_read(&upid, upid_sz,
-		   (void *)_(&pid->numbers) + (level * upid_sz));
+	probe_read_kernel(&upid, upid_sz,
+			  (void *)_(&pid->numbers) + (level * upid_sz));
 	return upid.nr;
 }
 
@@ -103,7 +103,7 @@ FUNC_INLINE __u32 event_find_parent_pid(struct task_struct *t)
 
 	if (!task)
 		return 0;
-	probe_read(&pid, sizeof(pid), _(&task->tgid));
+	probe_read_kernel(&pid, sizeof(pid), _(&task->tgid));
 	return pid;
 }
 
@@ -116,10 +116,10 @@ __event_find_parent(struct task_struct *task)
 
 #pragma unroll
 	for (i = 0; i < 4; i++) {
-		probe_read(&task, sizeof(task), _(&task->real_parent));
+		probe_read_kernel(&task, sizeof(task), _(&task->real_parent));
 		if (!task)
 			break;
-		probe_read(&pid, sizeof(pid), _(&task->tgid));
+		probe_read_kernel(&pid, sizeof(pid), _(&task->tgid));
 		value = execve_map_get_noinit(pid);
 		if (value && value->key.ktime != 0)
 			return value;
@@ -158,13 +158,13 @@ FUNC_INLINE struct execve_map_value *event_find_curr(__u32 *ppid, bool *walked)
 
 #pragma unroll
 	for (i = 0; i < 4; i++) {
-		probe_read(&pid, sizeof(pid), _(&task->tgid));
+		probe_read_kernel(&pid, sizeof(pid), _(&task->tgid));
 		value = execve_map_get_noinit(pid);
 		if (value && value->key.ktime != 0)
 			break;
 		value = 0;
 		*walked = 1;
-		probe_read(&task, sizeof(task), _(&task->real_parent));
+		probe_read_kernel(&task, sizeof(task), _(&task->real_parent));
 		if (!task)
 			break;
 	}