FIXME: building errors and warnings resolved for v6.8

Signed-off-by: shenping.matt <shenping.matt@bytedance.com>

Author: shenping-bd

driver/LKM/include/util.h

@@ -26,8 +26,6 @@
 #define NAME_TOO_LONG "-4"
 #define PID_TREE_MATEDATA_LEN  32
 
-static unsigned int ROOT_PID_NS_INUM;
-
 /*
  * macro definitions for legacy kernels
  */
@@ -55,34 +53,12 @@ static unsigned int ROOT_PID_NS_INUM;
  */
 extern unsigned long smith_kallsyms_lookup_name(const char *);
 
-extern char *__dentry_path(struct dentry *dentry, char *buf, int buflen);
+extern char *smith_dentry_path(struct dentry *dentry, char *buf, int buflen);
 
 extern u8 *smith_query_sb_uuid(struct super_block *sb);
 
 extern uint64_t hash_murmur_OAAT64(char *s, int len);
 
-static struct task_struct *smith_get_task_struct(struct task_struct *tsk)
-{
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 1, 0)
-    if (tsk && refcount_inc_not_zero(&tsk->usage))
-#else
-    if (tsk && atomic_inc_not_zero((atomic_t *)&tsk->usage))
-#endif
-        return tsk;
-    return NULL;
-}
-
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 39)
-extern void (*__smith_put_task_struct)(struct task_struct *t);
-static inline void smith_put_task_struct(struct task_struct *t)
-{
-	if (atomic_dec_and_test(&t->usage))
-		__smith_put_task_struct(t);
-}
-#else
-#define smith_put_task_struct(tsk)  put_task_struct(tsk)
-#endif
-
 #if defined(KGID_STRUCT_CHECK) && (!defined(KGID_CONFIG_CHECK) || \
     (defined(KGID_CONFIG_CHECK) && defined(CONFIG_UIDGID_STRICT_TYPE_CHECKS)))
 /* vanilla kernels >= 3.5.0, but ubuntu backported for 3.4 */
@@ -284,80 +260,6 @@ static __always_inline unsigned long __must_check smith_copy_from_user(void *to,
     __ret;                                                      \
 })
 
-static __always_inline char *smith_d_path(const struct path *path, char *buf, int buflen)
-{
-    char *name = DEFAULT_RET_STR;
-    if (buf) {
-        name = d_path(path, buf, buflen);
-        if (IS_ERR(name))
-            name = NAME_TOO_LONG;
-    }
-    return name;
-}
-
-/*
- * query task's executable image file, with mmap lock avoided, just because
- * mmput() could lead resched() (since it's calling might_sleep() interally)
- *
- * there could be races on mm->exe_file, but we could assure we can always
- * get a valid filp or NULL
- */
-static inline struct file *smith_get_task_exe_file(struct task_struct *task)
-{
-    struct file *exe = NULL;
-
-    /*
-     * get_task_mm/mmput must be avoided here
-     *
-     * mmput would put current task to sleep, which violates kprobe. or
-     * use mmput_async instead, but it's only available for after 4.7.0
-     * (and CONFIG_MMU is enabled)
-     */
-    task_lock(task);
-    if (task->mm && task->mm->exe_file) {
-        exe = task->mm->exe_file;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 1, 0)
-        if (!get_file_rcu(exe))
-            exe = NULL;
-#else
-        /* only inc f_count when it's not 0 to avoid races upon exe_file */
-        if (!atomic_long_inc_not_zero(&exe->f_count))
-            exe = NULL;
-#endif
-    }
-    task_unlock(task);
-
-    return exe;
-}
-
-// get full path of current task's executable image
-static __always_inline char *smith_get_exe_file(char *buffer, int size)
-{
-    char *exe_file_str = DEFAULT_RET_STR;
-    struct file *exe;
-
-    if (!buffer || !current->mm)
-        return exe_file_str;
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 1, 0) && LINUX_VERSION_CODE < KERNEL_VERSION(5, 15, 0)
-    /*
-     * 1) performance improvement for kernels >=4.1: use get_mm_exe_file instead
-     *    get_mm_exe_file internally uses rcu lock (with semaphore locks killed)
-     * 2) it's safe to directly access current->mm under current's own context
-     * 3) get_mm_exe_file() is no longer exported after kernel 5.15
-     */
-    exe = get_mm_exe_file(current->mm);
-#else
-    exe = smith_get_task_exe_file(current);
-#endif
-    if (exe) {
-        exe_file_str = smith_d_path(&exe->f_path, buffer, size);
-        fput(exe);
-    }
-
-    return exe_file_str;
-}
-
 static inline unsigned int __get_sessionid(void) {
     unsigned int sessionid = 0;
 #ifdef CONFIG_AUDITSYSCALL
@@ -366,32 +268,16 @@ static inline unsigned int __get_sessionid(void) {
     return sessionid;
 }
 
-static inline void __init_root_pid_ns_inum(void) {
-    struct pid *pid_struct;
-    struct task_struct *task;
-
-    pid_struct = find_get_pid(1);
-    task = pid_task(pid_struct,PIDTYPE_PID);
+static inline int __get_pgid(void) {
+    return task_pgrp_nr_ns(current, &init_pid_ns);
+}
 
-    smith_get_task_struct(task);
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
-    ROOT_PID_NS_INUM = task->nsproxy->pid_ns_for_children->ns.inum;
-#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 11, 0)
-    ROOT_PID_NS_INUM = task->nsproxy->pid_ns_for_children->proc_inum;
-#elif LINUX_VERSION_CODE >= KERNEL_VERSION(3, 8, 0)
-    ROOT_PID_NS_INUM = task->nsproxy->pid_ns->proc_inum;
-#else
-    /*
-     * For kernels < 3.8.0, id for pid namespaces isn't defined.
-     * So here we are using fixed values, no emulating any more,
-     * previously we were using image file's inode number.
-     */
-    ROOT_PID_NS_INUM = 0xEFFFFFFCU /* PROC_PID_INIT_INO */;
-#endif
-    smith_put_task_struct(task);
-    put_pid(pid_struct);
+static inline int __get_sid(void) {
+    return task_session_nr_ns(current, &init_pid_ns);
 }
 
+extern unsigned int ROOT_PID_NS_INUM;
+
 static inline unsigned int __get_pid_ns_inum(void) {
     unsigned int inum;
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
@@ -411,12 +297,4 @@ static inline unsigned int __get_pid_ns_inum(void) {
     return inum;
 }
 
-static inline int __get_pgid(void) {
-    return task_pgrp_nr_ns(current, &init_pid_ns);
-}
-
-static inline int __get_sid(void) {
-    return task_session_nr_ns(current, &init_pid_ns);
-}
-
 #endif /* UTIL_H */

driver/LKM/src/filter.c

@@ -27,9 +27,8 @@ static struct class *filter_class;
 static int filter_major;
 static char *sh_mem = NULL;
 
-struct rb_root execve_exe_allowlist = RB_ROOT;
-
-struct rb_root execve_argv_allowlist = RB_ROOT;
+static struct rb_root execve_exe_allowlist = RB_ROOT;
+static struct rb_root execve_argv_allowlist = RB_ROOT;
 
 static int execve_exe_allowlist_limit = 0;