1 files changed, 10 insertions, 10 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4f3a8e24b426..56608538a4ad 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -530,8 +530,6 @@ int trace_pid_write(struct trace_pid_list *filtered_pids,
                 ubuf += ret;
                 cnt -= ret;
 
-                parser.buffer[parser.idx] = 0;
-
                 ret = -EINVAL;
                 if (kstrtoul(parser.buffer, 0, &val))
                         break;
@@ -1236,18 +1234,18 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
                         cnt--;
                 }
 
+                parser->idx = 0;
+
                 /* only spaces were written */
-                if (isspace(ch)) {
+                if (isspace(ch) || !ch) {
                         *ppos += read;
                         ret = read;
                         goto out;
                 }
-
-                parser->idx = 0;
         }
 
         /* read the non-space input */
-        while (cnt && !isspace(ch)) {
+        while (cnt && !isspace(ch) && ch) {
                 if (parser->idx < parser->size - 1)
                         parser->buffer[parser->idx++] = ch;
                 else {
@@ -1262,12 +1260,14 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
         }
 
         /* We either got finished input or we have to wait for another call. */
-        if (isspace(ch)) {
+        if (isspace(ch) || !ch) {
                 parser->buffer[parser->idx] = 0;
                 parser->cont = false;
         } else if (parser->idx < parser->size - 1) {
                 parser->cont = true;
                 parser->buffer[parser->idx++] = ch;
+                /* Make sure the parsed string always terminates with '\0'. */
+                parser->buffer[parser->idx] = 0;
         } else {
                 ret = -EINVAL;
                 goto out;
@@ -5616,7 +5616,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file)
         return 0;
 }
 
-static unsigned int
+static __poll_t
 trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table)
 {
         struct trace_array *tr = iter->tr;
@@ -5635,7 +5635,7 @@ trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_tabl
                                              filp, poll_table);
 }
 
-static unsigned int
+static __poll_t
 tracing_poll_pipe(struct file *filp, poll_table *poll_table)
 {
         struct trace_iterator *iter = filp->private_data;
@@ -6589,7 +6589,7 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
         return ret;
 }
 
-static unsigned int
+static __poll_t
 tracing_buffers_poll(struct file *filp, poll_table *poll_table)
 {
         struct ftrace_buffer_info *info = filp->private_data;