dpu-utilities/0006-code-style-problem-fix.patch

From ba079528b3c1c0fd911ee98353685c4116c8e6f8 Mon Sep 17 00:00:00 2001
From: Deng Guangxing <dengguangxing@huawei.com>
Date: Mon, 11 Dec 2023 14:20:51 +0800
Subject: [PATCH 06/12] code-style problem fix

Signed-off-by: Deng Guangxing <dengguangxing@huawei.com>
---
 qtfs/ipc/uds_event.c          |   6 +-
 qtfs/qtfs/fifo.c              |  39 ++++++-------
 qtfs/qtfs/proc.c              |  10 ++--
 qtfs/qtfs/qtfs-mod.c          |   6 +-
 qtfs/qtfs/sb.c                |   7 +--
 qtfs/qtfs_common/qtfs_check.c | 103 ++++++++++++----------------------
 qtfs/rexec/rexec.c            |  11 ++--
 7 files changed, 77 insertions(+), 105 deletions(-)

diff --git a/qtfs/ipc/uds_event.c b/qtfs/ipc/uds_event.c
index 4253deb..78a2a97 100644
--- a/qtfs/ipc/uds_event.c
+++ b/qtfs/ipc/uds_event.c
@@ -524,7 +524,7 @@ static int uds_msg_scm_regular_file(int scmfd, int tcpfd, struct uds_event_globa
 		uds_err("failed to calloc memory");
 		return EVENT_ERR;
 	}
-	sprintf(fdproc, "/proc/self/fd/%d", scmfd);
+	snprintf(fdproc, UDS_PATH_MAX, "/proc/self/fd/%d", scmfd);
 	ret = readlink(fdproc, p_scmr->path, UDS_PATH_MAX);
 	if (ret < 0) {
 		uds_err("readlink:%s error, ret:%d, errno:%d", fdproc, ret, errno);
@@ -562,7 +562,7 @@ static int uds_msg_scm_fifo_file(int scmfd, int tcpfd, struct uds_event_global_v
 	p_get->msgtype = MSG_SCM_PIPE;
 	p_get->msglen = sizeof(struct uds_stru_scm_pipe);
 
-	sprintf(path, "/proc/self/fd/%d", scmfd);
+	snprintf(path, FDPATH_LEN, "/proc/self/fd/%d", scmfd);
 	lstat(path, &st);
 	if (st.st_mode & S_IRUSR) {
 		p_pipe->dir = SCM_PIPE_READ;
@@ -1085,7 +1085,7 @@ int uds_event_debug_level(void *arg, int epfd, struct uds_event_global_var *p_ev
 
 	uds_log("debug level accept a new connection, current level:%s change to:%s", UDS_LOG_STR(cur), UDS_LOG_STR(p_uds_var->loglevel));
 
-	len = sprintf(p_event_var->iov_base,	"+---------------UDS LOG LEVEL UPDATE--------------+\n"
+	len = snprintf(p_event_var->iov_base, p_event_var->iov_len,	"+---------------UDS LOG LEVEL UPDATE--------------+\n"
 						"+ Log level is:%s before, now change to :%s.\n"
 						"+-------------------------------------------------+\n", UDS_LOG_STR(cur), UDS_LOG_STR(p_uds_var->loglevel));
 
diff --git a/qtfs/qtfs/fifo.c b/qtfs/qtfs/fifo.c
index 829ce66..f072706 100644
--- a/qtfs/qtfs/fifo.c
+++ b/qtfs/qtfs/fifo.c
@@ -26,9 +26,9 @@
 
 static void qtfs_fifo_put_file(struct file *file)
 {
-	struct private_data *priv = file->private_data;
-	struct qtfs_conn_var_s *pvar = (struct qtfs_conn_var_s *)priv->priv;
-	if (pvar == NULL) {
+	struct private_data *priv;
+	struct qtfs_conn_var_s *pvar;
+	if (file == NULL || (priv = file->private_data) == NULL || (pvar = (struct qtfs_conn_var_s *)priv->priv) == NULL) {
 		qtfs_err("fifo private data invalid to put");
 		return;
 	}
@@ -110,8 +110,8 @@ int qtfs_fifo_open(struct inode *inode, struct file *file)
 
 ssize_t qtfs_fifo_readiter(struct kiocb *kio, struct iov_iter *iov)
 {
-	struct private_data *priv = kio->ki_filp->private_data;
-	struct qtfs_conn_var_s *pvar = (struct qtfs_conn_var_s *)priv->priv;
+	struct private_data *priv;
+	struct qtfs_conn_var_s *pvar;
 	struct qtreq_fifo_read *req;
 	struct qtrsp_fifo_read *rsp;
 	int total = 0;
@@ -121,7 +121,7 @@ ssize_t qtfs_fifo_readiter(struct kiocb *kio, struct iov_iter *iov)
 		qtfs_err("signal SIGURG return eintr");
 		return -EINTR;
 	}
-	if (pvar == NULL || !virt_addr_valid(pvar)) {
+	if (!kio || !kio->ki_filp || (priv = kio->ki_filp->private_data) == NULL || (pvar = (struct qtfs_conn_var_s *)priv->priv) == NULL || !virt_addr_valid(pvar)) {
 		qtfs_err("invalid fifo read req, private data is invalid");
 		return -EFAULT;
 	}
@@ -154,8 +154,8 @@ ssize_t qtfs_fifo_readiter(struct kiocb *kio, struct iov_iter *iov)
 
 ssize_t qtfs_fifo_writeiter(struct kiocb *kio, struct iov_iter *iov)
 {
-	struct private_data *priv = kio->ki_filp->private_data;
-	struct qtfs_conn_var_s *pvar = (struct qtfs_conn_var_s *)priv->priv;
+	struct private_data *priv;
+	struct qtfs_conn_var_s *pvar;
 	struct qtreq_fifo_write *req;
 	struct qtrsp_fifo_write *rsp;
 
@@ -163,7 +163,7 @@ ssize_t qtfs_fifo_writeiter(struct kiocb *kio, struct iov_iter *iov)
 		qtfs_err("signal SIGURG return eintr");
 		return -EINTR;
 	}
-	if (pvar == NULL || !virt_addr_valid(pvar)) {
+	if (!kio || !kio->ki_filp || (priv = kio->ki_filp->private_data) == NULL || (pvar = (struct qtfs_conn_var_s *)priv->priv) == NULL || !virt_addr_valid(pvar)) {
 		qtfs_err("invalid fifo write req, private data is invalid");
 		return -EFAULT;
 	}
@@ -182,10 +182,11 @@ ssize_t qtfs_fifo_writeiter(struct kiocb *kio, struct iov_iter *iov)
 
 int qtfs_fifo_release(struct inode *inode, struct file *file)
 {
-	struct private_data *priv = file->private_data;
-	struct qtfs_conn_var_s *pvar = (struct qtfs_conn_var_s *)priv->priv;
+	struct private_data *priv;
+	struct qtfs_conn_var_s *pvar;
 	struct qtrsp_fifo_close *rsp = NULL;
-	if (pvar == NULL) {
+
+	if (file == NULL || (priv = file->private_data) == NULL || (pvar = (struct qtfs_conn_var_s *)priv->priv) == NULL) {
 		qtfs_err("invalid fifo write req, private data is invalid");
 		return -EFAULT;
 	}
@@ -202,22 +203,22 @@ int qtfs_fifo_release(struct inode *inode, struct file *file)
 __poll_t
 qtfs_poll(struct file *filp, poll_table *wait)
 {
-	struct qtfs_inode_priv *priv = filp->f_inode->i_private;
+	struct qtfs_inode_priv *priv;
 	__poll_t mask = 0;
 	struct list_head *p;
 	struct qtfs_conn_var_s *pvar;
 	struct qtreq_poll *req;
 	struct qtrsp_poll *rsp;
-	struct private_data *fpriv = (struct private_data *)filp->private_data;
-
-	poll_wait(filp, &priv->readq, wait);
-
-	p = &priv->readq.head;
+	struct private_data *fpriv;
 
-	if (fpriv->fd < 0) {
+	if (!filp || !filp->f_inode || !(priv = filp->f_inode->i_private) || !(fpriv = (struct private_data *)filp->private_data) || fpriv->fd < 0) {
 		qtfs_err("fifo poll priv file invalid.");
 		return 0;
 	}
+
+	poll_wait(filp, &priv->readq, wait);
+	p = &priv->readq.head;
+
 	pvar = qtfs_conn_get_param();
 	if (pvar == NULL) {
 		qtfs_err("qtfs fifo poll get param failed.");
diff --git a/qtfs/qtfs/proc.c b/qtfs/qtfs/proc.c
index 70238ea..deea1c8 100644
--- a/qtfs/qtfs/proc.c
+++ b/qtfs/qtfs/proc.c
@@ -147,7 +147,7 @@ struct dentry *qtfs_proc_lookup(struct inode *parent_inode, struct dentry *child
 	if (pid > 0) {
 		sscanf(cpath, "/proc/%s", tmp);
 		memset(cpath, 0, MAX_PATH_LEN);
-		sprintf(cpath, "/local_proc/%s", tmp);
+		snprintf(cpath, MAX_PATH_LEN, "/local_proc/%s", tmp);
 		qtfs_debug("[%s]: get path from local: %s\n", __func__, cpath);
 		ret = kern_path(cpath, 0, &spath);
 		if(ret) {
@@ -208,13 +208,13 @@ const char *qtfs_proc_getlink(struct dentry *dentry,
 	}
 
 	if (!strncmp(path, "/proc/self", 11)) {
-		sprintf(link, "/local_proc/%d", (int)current->pid);
+		snprintf(link, MAX_PATH_LEN, "/local_proc/%d", (int)current->pid);
 		qtfs_info("[%s] success: %s getlink: %s", __func__, path, link);
 		goto link_local;
 	}
 
 	if (!strcmp(path, "/proc/mounts")) {
-		sprintf(link, "/proc/1/mounts");
+		snprintf(link, MAX_PATH_LEN, "/proc/1/mounts");
 		qtfs_info("[%s] success: %s getlink /proc/1/mounts", __func__, path);
 		goto link_local;
 	}
@@ -222,7 +222,7 @@ const char *qtfs_proc_getlink(struct dentry *dentry,
 	pid = is_local_process(path);
 	if (pid > 0) {
 		sscanf(path, "/proc/%s", tmp);
-		sprintf(link, "/local_proc/%s", tmp);
+		snprintf(link, MAX_PATH_LEN, "/local_proc/%s", tmp);
 		qtfs_info("[%s] success: %s getlink: %s", __func__, path, link);
 		goto link_local;
 	}
@@ -274,7 +274,7 @@ int qtfs_proc_getattr(const struct path *path, struct kstat *stat, u32 req_mask,
 	pid = is_local_process(cpath);
 	if (pid > 0) {
 		sscanf(cpath, "/proc/%s", tmp);
-		sprintf(local_path, "/local_proc/%s", tmp);
+		snprintf(local_path, MAX_PATH_LEN, "/local_proc/%s", tmp);
 		ret = kern_path(local_path, 0, &spath);
 		if (ret) {
 			qtfs_err("[%s]: kern_path(%s) failed: %d", __func__, local_path, ret);
diff --git a/qtfs/qtfs/qtfs-mod.c b/qtfs/qtfs/qtfs-mod.c
index 0b6cd65..d49e9a2 100644
--- a/qtfs/qtfs/qtfs-mod.c
+++ b/qtfs/qtfs/qtfs-mod.c
@@ -23,6 +23,8 @@
 #include "syscall.h"
 #include "symbol_wrapper.h"
 
+#define MAX_RETRY 5
+
 static struct file_system_type qtfs_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= QTFS_FSTYPE_NAME,
@@ -86,7 +88,7 @@ retry:
 			pvar->miss_proc = 0;
 		}
 		// miss message retry would result in block
-		if (retrytimes >= 5) {
+		if (retrytimes >= MAX_RETRY) {
 			qtfs_err("qtfs conn recv get mismatch seq_num too many times, stop retrying, signal:0x%lx", (unsigned long)current->pending.signal.sig[0]);
 			return NULL;
 		}
@@ -98,7 +100,7 @@ retry:
 			qtinfo_cntinc(QTINF_RESTART_SYS);
 			qtinfo_recverrinc(req->type);
 		}
-		if (retrytimes >= 5 && ret == -EINTR) {
+		if (retrytimes >= MAX_RETRY && ret == -EINTR) {
 			qtfs_err("qtfs conn recv get retry signal(%d) too many times, stop retrying, signal:0x%lx", ret, (unsigned long)current->pending.signal.sig[0]);
 			return ERR_PTR(ret);
 		}
diff --git a/qtfs/qtfs/sb.c b/qtfs/qtfs/sb.c
index fb60261..a5bcc8e 100644
--- a/qtfs/qtfs/sb.c
+++ b/qtfs/qtfs/sb.c
@@ -155,8 +155,8 @@ int qtfs_readdir(struct file *filp, struct dir_context *ctx)
 	int count = 0;
 	struct getdents_callback64 *buf = container_of(ctx, struct getdents_callback64, ctx);
 
-	if (!pvar) {
-		qtfs_err("Failed to get qtfs sock var");
+	if (!pvar || !buf) {
+		qtfs_err("Failed to get qtfs sock var(%p) or gentdents(%p)", pvar, buf);
 		return -EINVAL;
 	}
 
@@ -168,7 +168,6 @@ int qtfs_readdir(struct file *filp, struct dir_context *ctx)
 	req = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_SEND);
 	rsp = pvar->conn_ops->get_conn_msg_buf(pvar, QTFS_RECV);
 	QTFS_FULLNAME(req->path, filp->f_path.dentry, sizeof(req->path));
-	// req->count = sizeof(rsp->dirent);
 	count = sizeof(rsp->dirent);
 	if (buf && buf->count > 0 && buf->count < sizeof(rsp->dirent)) {
 		qtfs_info("readdir use input buf size(%d), prev_reclen(%d)", buf->count, buf->prev_reclen);
@@ -198,7 +197,6 @@ int qtfs_readdir(struct file *filp, struct dir_context *ctx)
 		}
 		dirent = (struct qtfs_dirent64 *)&rsp->dirent[idx];
 		namelen = strlen(dirent->d_name);
-		// ret = dir_emit(ctx, dirent->d_name, namelen, dirent->d_ino, dirent->d_type);
 		ret = ctx->actor(ctx, dirent->d_name, namelen, ctx->pos, dirent->d_ino, dirent->d_type);
 		if (ret == -EINTR) {
 			err = ret;
@@ -210,7 +208,6 @@ int qtfs_readdir(struct file *filp, struct dir_context *ctx)
 				(void *)dirent - (void *)rsp->dirent, dirent->d_name, ret, dirent->d_reclen, namelen, dirent->d_ino, dirent->d_type);
 	}
 
-	// ctx->pos = (rsp->d.over) ? -1 : rsp->d.pos;
 	ctx->pos = rsp->d.pos;
 	qtfs_info("qtfs readdir<%s> success ret:%d vldcnt:%d dircnt:%d over:%d pos:%lld.",
 			req->path, rsp->d.ret, rsp->d.vldcnt, dircnt, rsp->d.over, ctx->pos);
diff --git a/qtfs/qtfs_common/qtfs_check.c b/qtfs/qtfs_common/qtfs_check.c
index 8daad39..e2a7ec1 100644
--- a/qtfs/qtfs_common/qtfs_check.c
+++ b/qtfs/qtfs_common/qtfs_check.c
@@ -15,6 +15,26 @@
 #include "req.h"
 #include "qtfs_check.h"
 
+#define do_path_check(ops)	\
+(	\
+	{	\
+	struct qtreq_##ops *req = TOREQ; \
+	if (check_string(req->path, sizeof(req->path))) \
+		return QTFS_CHECK_ERR; \
+	return QTFS_CHECK_OK; \
+	} \
+)
+
+#define do_fd_check(ops)	\
+(	\
+	{	\
+	struct qtreq_##ops *req = TOREQ; \
+	if (check_fd(req->fd)) \
+		return QTFS_CHECK_ERR; \
+	return QTFS_CHECK_OK; \
+	} \
+)
+
 /*
 	检查原则：
 	1. 基本数据类型，据实严格判断合法范围，有数组、指针操作的注意数组越界或指针飞踩；
@@ -26,7 +46,7 @@
 // string类型基本防护，在max范围内最后一个字符必须是结束符，防止越界访问
 static inline bool check_string(char *str, size_t max)
 {
-	if (max == 0)
+	if (str == NULL || max == 0)
 		return false;
 	if (str[max - 1] != '\0')
 		return true;
@@ -50,37 +70,24 @@ int req_check_none(void *in)
 
 int req_check_mount(void *in)
 {
-	struct qtreq_mount *req = TOREQ;
-
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(mount);
 }
 
 int req_check_open(void *in)
 {
-	struct qtreq_open *req = TOREQ;
 
 	// flags 和 mode如果错误syscall会报错，不会有安全风险
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(open);
 }
 
 int req_check_close(void *in)
 {
-	struct qtreq_close *req = TOREQ;
-	if (check_fd(req->fd))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_fd_check(close);
 }
 
 int req_check_readiter(void *in)
 {
-	struct qtreq_readiter *req = TOREQ;
-	if (check_fd(req->fd))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_fd_check(readiter);
 }
 
 int req_check_write(void *in)
@@ -111,26 +118,17 @@ int req_check_readdir(void *in)
 
 int req_check_mkdir(void *in)
 {
-	struct qtreq_mkdir *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(mkdir);
 }
 
 int req_check_rmdir(void *in)
 {
-	struct qtreq_rmdir *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(rmdir);
 }
 
 int req_check_getattr(void *in)
 {
-	struct qtreq_getattr *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(getattr);
 }
 
 int req_check_setattr(void *in)
@@ -143,26 +141,17 @@ int req_check_setattr(void *in)
 
 int req_check_icreate(void *in)
 {
-	struct qtreq_icreate *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(icreate);
 }
 
 int req_check_mknod(void *in)
 {
-	struct qtreq_mknod *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(mknod);
 }
 
 int req_check_unlink(void *in)
 {
-	struct qtreq_unlink *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(unlink);
 }
 
 int req_check_symlink(void *in)
@@ -195,10 +184,7 @@ int req_check_link(void *in)
 
 int req_check_getlink(void *in)
 {
-	struct qtreq_getlink *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(getlink);
 }
 
 int req_check_rename(void *in)
@@ -216,10 +202,7 @@ int req_check_rename(void *in)
 }
 int req_check_xattrlist(void *in)
 {
-	struct qtreq_xattrlist *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(xattrlist);
 }
 
 int req_check_xattrget(void *in)
@@ -277,18 +260,12 @@ int req_check_sysumount(void *in)
 
 int req_check_fifopoll(void *in)
 {
-	struct qtreq_poll *req = TOREQ;
-	if (check_fd(req->fd))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_fd_check(poll);
 }
 
 int req_check_statfs(void *in)
 {
-	struct qtreq_statfs *req = TOREQ;
-	if (check_string(req->path, sizeof(req->path)))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_path_check(statfs);
 }
 
 int req_check_ioctl(void *in)
@@ -303,18 +280,12 @@ int req_check_ioctl(void *in)
 
 int req_check_epoll_ctl(void *in)
 {
-	struct qtreq_epollctl *req = TOREQ;
-	if (check_fd(req->fd))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_fd_check(epollctl);
 }
 
 int req_check_llseek(void *in)
 {
-	struct qtreq_llseek *req = TOREQ;
-	if (check_fd(req->fd))
-		return QTFS_CHECK_ERR;
-	return QTFS_CHECK_OK;
+	do_fd_check(llseek);
 }
 
 int req_check_sc_kill(void *in)
diff --git a/qtfs/rexec/rexec.c b/qtfs/rexec/rexec.c
index e24c0ad..f905cfa 100644
--- a/qtfs/rexec/rexec.c
+++ b/qtfs/rexec/rexec.c
@@ -150,7 +150,7 @@ static int rexec_conn_msg(struct rexec_client_event *evt)
 				rexec_err("Rexec pidmap msg > 1 error.");
 				return REXEC_EVENT_OK;
 			}
-			sprintf(path, "%s/%d", REXEC_PIDMAP_PATH, mypid);
+			snprintf(path, REXEC_PIDMAP_PATH_LEN, "%s/%d", REXEC_PIDMAP_PATH, mypid);
 			fd = open(path, O_CREAT|O_WRONLY, 0600);
 			if (fd < 0) {
 				rexec_err("Rexec create pidmap:%d-%d failed, path:%s open failed:%d",
@@ -170,7 +170,7 @@ static int rexec_conn_msg(struct rexec_client_event *evt)
 				rexec_err("Rexec pidmap file:%s lseek 0 failed errno:%d rexec exit", path, err);
 				return REXEC_EVENT_EXIT;
 			}
-			sprintf(buf, "%d", peerpid);
+			snprintf(buf, REXEC_PID_LEN, "%d", peerpid);
 			if ((err = write(fd, buf, strlen(buf))) <= 0) {
 				rexec_err("Rexec pidmap file:%s write pid:%d failed errno:%d rexec exit.", path, peerpid, err);
 				return REXEC_EVENT_EXIT;
@@ -316,7 +316,7 @@ static int rexec_run(int efd, int connfd, char *argv[])
 	// clear pidmap file
 	if (pidfd > 0) {
 		char path[32] = {0};
-		sprintf(path, "%s/%d", REXEC_PIDMAP_PATH, getpid());
+		snprintf(path, 32, "%s/%d", REXEC_PIDMAP_PATH, getpid());
 		close(pidfd);
 		remove(path);
 	}
@@ -357,7 +357,7 @@ void rexec_clear_pids()
 			continue;
 
 		memset(path, 0, sizeof(path));
-		sprintf(path, "%s/%s", REXEC_PIDMAP_PATH, entry->d_name);
+		snprintf(path, REXEC_PIDMAP_PATH_LEN, "%s/%s", REXEC_PIDMAP_PATH, entry->d_name);
 		fd = open(path, O_RDONLY);
 		if (fd <= 0) {
 			rexec_err("open pid file:%s failed", path);
@@ -401,7 +401,7 @@ static int rexec_get_fdinfo(struct dirent *fdentry, struct rexec_fdinfo *fdinfo)
 		return -1;
 	if (!rexec_is_reg_file(fd))
 		return -1;
-	sprintf(path, "/proc/self/fd/%s", fdentry->d_name);
+	snprintf(path, 32, "/proc/self/fd/%s", fdentry->d_name);
 	ret = readlink(path, fdinfo->path, REXEC_PATH_MAX);
 	if (ret < 0) {
 		rexec_err("Get fd:%d link failed.", fd);
@@ -624,6 +624,7 @@ static int rexec_send_binary_msg(int efd, int argc, char *argv[], int arglen, ch
 	pmsg->argc = argc - 1; // for remote binary's argc is argc-1
 	// pmsg->msg is like: "binary"\0"argv[1]"\0"argv[2]"\0"..."
 	pmsg->msglen = rexec_msg_fill_argv(pmsg->argc, &argv[1], bufmsg);
+	// bufmsg len has been calculated to make sure it will not overflow.
 	strcpy(&bufmsg[pmsg->msglen], fds_json);
 	pmsg->msglen += strlen(fds_json);
 	free(fds_json);
-- 
2.37.1 (Apple Git-137.1)