diff options
| -rw-r--r-- | kernel/trace/trace.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index caa4051ce778..78d56614c95b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2381,9 +2381,11 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, struct tracer *t; char buf[max_tracer_type_len+1]; int i; + size_t ret; if (cnt > max_tracer_type_len) cnt = max_tracer_type_len; + ret = cnt; if (copy_from_user(&buf, ubuf, cnt)) return -EFAULT; @@ -2399,7 +2401,11 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, if (strcmp(t->name, buf) == 0) break; } - if (!t || t == current_trace) + if (!t) { + ret = -EINVAL; + goto out; + } + if (t == current_trace) goto out; if (current_trace && current_trace->reset) @@ -2412,9 +2418,10 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, out: mutex_unlock(&trace_types_lock); - filp->f_pos += cnt; + if (ret == cnt) + filp->f_pos += cnt; - return cnt; + return ret; } static ssize_t |