[PATCH 5/8] ksym_tracer: NIL-terminate user input filter

Li Zefan
2009-07-07T05:54:18Z

Make sure the user input string is NULL-terminated.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
---
kernel/trace/trace_ksym.c | 7 ++-----
1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index 72fcb46..8cbed5a 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -264,11 +264,7 @@ static ssize_t ksym_trace_filter_write(struct file *file,
unsigned long ksym_addr = 0;
int ret, op, changed = 0;

- /* Ignore echo "" > ksym_trace_filter */
- if (count == 0)
- return 0;
-
- input_string = kzalloc(count, GFP_KERNEL);
+ input_string = kzalloc(count + 1, GFP_KERNEL);
if (!input_string)
return -ENOMEM;

@@ -276,6 +272,7 @@ static ssize_t ksym_trace_filter_write(struct file *file,
kfree(input_string);
return -EFAULT;
}
+ input_string[count] = '\0';

ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr);
if (ret < 0) {
--
1.5.4.rc3