From db547eecf160139c8e2b03885a071462b4f7ed8e Mon Sep 17 00:00:00 2001
From: sidex15 <24408329+sidex15@users.noreply.github.com>
Date: Thu, 15 May 2025 17:38:34 +0800
Subject: [PATCH] kernel: kpm: add compatibility for kernel 4.14 and lower
 (#76)

`thread_pid` is not defined in kernel 4.14 and lower, leading to compilation issue.
To fix this, use `pids[PIDTYPE_PID].pid` for kernel versions 4.14 and lower.
Else use `thread_pid` for kernel versions 4.19 and higher.

Reference: https://github.com/yanivagman/BPFroid/blob/107717913bce95d6d5c232bf8dc4b11932b59d50/tracee/tracee.bpf.c#L354
---
 kernel/kpm/super_access.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/kpm/super_access.c b/kernel/kpm/super_access.c
index 0829bfda..7a61e22f 100644
--- a/kernel/kpm/super_access.c
+++ b/kernel/kpm/super_access.c
@@ -167,7 +167,11 @@ DYNAMIC_STRUCT_BEGIN(task_struct)
     DEFINE_MEMBER(task_struct, group_leader)
     DEFINE_MEMBER(task_struct, mm)
     DEFINE_MEMBER(task_struct, active_mm)
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 19, 0) 
+    DEFINE_MEMBER(task_struct, pids[PIDTYPE_PID].pid)
+#else
     DEFINE_MEMBER(task_struct, thread_pid)
+#endif
     DEFINE_MEMBER(task_struct, files)
     DEFINE_MEMBER(task_struct, seccomp)
 #ifdef CONFIG_THREAD_INFO_IN_TASK