Re: [PATCH] tracing: use strlcpy instead of strncpy

Lai Jiangshan
2009-05-19T01:54:57Z

strlcpy() will add '\0' for the copied string.

[Impact] cleanup

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 05b4747..9359e85 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -434,8 +434,7 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
if (!buts->buf_size || !buts->buf_nr)
return -EINVAL;

- strncpy(buts->name, name, BLKTRACE_BDEV_SIZE);
- buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0';
+ strlcpy(buts->name, name, BLKTRACE_BDEV_SIZE);

/*
* some device names have larger paths - convert the slashes
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 665a915..2484555 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -133,7 +133,7 @@ static char *default_bootup_tracer;

static int __init set_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
+ strlcpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = 1;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 6e735d4..e08c952 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -155,8 +155,8 @@ struct trace_boot_ret {
struct trace_branch {
struct trace_entry ent;
unsigned line;
- char func[TRACE_FUNC_SIZE+1];
- char file[TRACE_FILE_SIZE+1];
+ char func[TRACE_FUNC_SIZE];
+ char file[TRACE_FILE_SIZE];
char correct;
};

diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 7a7a9fd..a84e036 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -67,10 +67,8 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect)
p--;
p++;

- strncpy(entry->func, f->func, TRACE_FUNC_SIZE);
- strncpy(entry->file, p, TRACE_FILE_SIZE);
- entry->func[TRACE_FUNC_SIZE] = 0;
- entry->file[TRACE_FILE_SIZE] = 0;
+ strlcpy(entry->func, f->func, TRACE_FUNC_SIZE);
+ strlcpy(entry->file, p, TRACE_FILE_SIZE);
entry->line = f->line;
entry->correct = val == expect;

diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h
index 5e32e37..2ae6679 100644
--- a/kernel/trace/trace_event_types.h
+++ b/kernel/trace/trace_event_types.h
@@ -122,10 +122,10 @@ TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore,
TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned int, line, line)
- TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func,
- TRACE_FUNC_SIZE+1, func)
- TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file,
- TRACE_FUNC_SIZE+1, file)
+ TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE], func,
+ TRACE_FUNC_SIZE, func)
+ TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE], file,
+ TRACE_FUNC_SIZE, file)
TRACE_FIELD(char, correct, correct)
),
TP_RAW_FMT("%u:%s:%s (%u)")