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Diffstat (limited to 'kernel/trace/trace_syscalls.c')
-rw-r--r--kernel/trace/trace_syscalls.c42
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];
}