[PATCH v2] tracing/eprobe: Replace snprintf with memcpy

From: Quanfa Fu
Date: Sun Jan 08 2023 - 22:34:00 EST


No need to check for negative return value from snprintf() as the
code does not return negative values. Replace snprintf with memcpy.

Signed-off-by: Quanfa Fu <quanfafu@xxxxxxxxx>

-----
V1 -> V2: memory allc uses kzalloc and replace snprintf with memcpy
---
kernel/trace/trace_eprobe.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index 352b65e2b910..56eb39f495f6 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -905,7 +905,7 @@ static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[
static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const char *argv[])
{
struct event_filter *dummy = NULL;
- int i, ret, len = 0;
+ int i, ret, arg_len, len = 0;
char *p;

if (argc == 0) {
@@ -923,17 +923,17 @@ static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const ch

p = ep->filter_str;
for (i = 0; i < argc; i++) {
- ret = snprintf(p, len, "%s ", argv[i]);
- if (ret < 0)
- goto error;
- if (ret > len) {
- ret = -E2BIG;
- goto error;
- }
- p += ret;
- len -= ret;
+ arg_len = strlen(argv[i]);
+ memcpy((void *)p, argv[i], arg_len);
+
+ if (i == argc - 1)
+ p[arg_len] = '\0';
+ else
+ p[arg_len] = ' ';
+
+ p += arg_len + 1;
+ len -= arg_len + 1;
}
- p[-1] = '\0';

/*
* Ensure the filter string can be parsed correctly. Note, this
--
2.31.1