1 files changed, 30 insertions, 12 deletions

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 5c9fe08d2093..ee7b5a0bb9f8 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -60,6 +60,19 @@ extern struct syscall_metadata *__stop_syscalls_metadata[];
 
 static struct syscall_metadata **syscalls_metadata;
 
+#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME
+static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
+{
+        /*
+         * Only compare after the "sys" prefix. Archs that use
+         * syscall wrappers may have syscalls symbols aliases prefixed
+         * with "SyS" instead of "sys", leading to an unwanted
+         * mismatch.
+         */
+        return !strcmp(sym + 3, name + 3);
+}
+#endif
+
 static __init struct syscall_metadata *
 find_syscall_meta(unsigned long syscall)
 {
@@ -72,14 +85,11 @@ find_syscall_meta(unsigned long syscall)
         stop = __stop_syscalls_metadata;
         kallsyms_lookup(syscall, NULL, NULL, NULL, str);
 
+        if (arch_syscall_match_sym_name(str, "sys_ni_syscall"))
+                return NULL;
+
         for ( ; start < stop; start++) {
-                /*
-                 * Only compare after the "sys" prefix. Archs that use
-                 * syscall wrappers may have syscalls symbols aliases prefixed
-                 * with "SyS" instead of "sys", leading to an unwanted
-                 * mismatch.
-                 */
-                if ((*start)->name && !strcmp((*start)->name + 3, str + 3))
+                if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))
                         return *start;
         }
         return NULL;
@@ -359,7 +369,7 @@ int reg_event_syscall_enter(struct ftrace_event_call *call)
         int num;
 
         num = ((struct syscall_metadata *)call->data)->syscall_nr;
-        if (num < 0 || num >= NR_syscalls)
+        if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
                 return -ENOSYS;
         mutex_lock(&syscall_trace_lock);
         if (!sys_refcount_enter)
@@ -377,7 +387,7 @@ void unreg_event_syscall_enter(struct ftrace_event_call *call)
         int num;
 
         num = ((struct syscall_metadata *)call->data)->syscall_nr;
-        if (num < 0 || num >= NR_syscalls)
+        if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
                 return;
         mutex_lock(&syscall_trace_lock);
         sys_refcount_enter--;
@@ -393,7 +403,7 @@ int reg_event_syscall_exit(struct ftrace_event_call *call)
         int num;
 
         num = ((struct syscall_metadata *)call->data)->syscall_nr;
-        if (num < 0 || num >= NR_syscalls)
+        if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
                 return -ENOSYS;
         mutex_lock(&syscall_trace_lock);
         if (!sys_refcount_exit)
@@ -411,7 +421,7 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call)
         int num;
 
         num = ((struct syscall_metadata *)call->data)->syscall_nr;
-        if (num < 0 || num >= NR_syscalls)
+        if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
                 return;
         mutex_lock(&syscall_trace_lock);
         sys_refcount_exit--;
@@ -424,6 +434,14 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call)
 int init_syscall_trace(struct ftrace_event_call *call)
 {
         int id;
+        int num;
+
+        num = ((struct syscall_metadata *)call->data)->syscall_nr;
+        if (num < 0 || num >= NR_syscalls) {
+                pr_debug("syscall %s metadata not mapped, disabling ftrace event\n",
+                                ((struct syscall_metadata *)call->data)->name);
+                return -ENOSYS;
+        }
 
         if (set_syscall_print_fmt(call) < 0)
                 return -ENOMEM;
@@ -438,7 +456,7 @@ int init_syscall_trace(struct ftrace_event_call *call)
         return id;
 }
 
-unsigned long __init arch_syscall_addr(int nr)
+unsigned long __init __weak arch_syscall_addr(int nr)
 {
         return (unsigned long)sys_call_table[nr];
 }