[for-next][PATCH 2/6] tracing: Clear parser->idx if only spaces are read

From: Steven Rostedt
Date: Wed Jan 24 2018 - 13:37:03 EST


From: Changbin Du <changbin.du@xxxxxxxxx>

If only spaces were read while parsing the next string, then parser->idx should be
cleared in order to make trace_parser_loaded() return false.

Link: http://lkml.kernel.org/r/1516093350-12045-3-git-send-email-changbin.du@xxxxxxxxx

Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/trace.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c00a31d18f8a..cb90435e63da 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1236,14 +1236,14 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
cnt--;
}

+ parser->idx = 0;
+
/* only spaces were written */
if (isspace(ch) || !ch) {
*ppos += read;
ret = read;
goto out;
}
-
- parser->idx = 0;
}

/* read the non-space input */
--
2.15.1