From 23d04dde2496ffcd527a0bb5bc81faf4c85dbd9e Mon Sep 17 00:00:00 2001
From: "Todd C. Miller" <Todd.Miller@sudo.ws>
Date: Tue, 21 Sep 2021 19:09:21 -0600
Subject: [PATCH] iolog_nextid(): make iolog_dir argument const. We make a copy
 of the directory so there's no real reason that parameter can't be const.

---
 include/sudo_iolog.h     |  2 +-
 lib/iolog/iolog_nextid.c | 18 +++++++++++++-----
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/include/sudo_iolog.h b/include/sudo_iolog.h
index 16e0c3a97..e405e9665 100644
--- a/include/sudo_iolog.h
+++ b/include/sudo_iolog.h
@@ -111,7 +111,7 @@ bool iolog_close(struct iolog_file *iol, const char **errstr);
 bool iolog_eof(struct iolog_file *iol);
 bool iolog_mkdtemp(char *path);
 bool iolog_mkpath(char *path);
-bool iolog_nextid(char *iolog_dir, char sessid[7]);
+bool iolog_nextid(const char *iolog_dir, char sessid[7]);
 bool iolog_open(struct iolog_file *iol, int dfd, int iofd, const char *mode);
 bool iolog_write_info_file(int dfd, struct eventlog *evlog);
 char *iolog_gets(struct iolog_file *iol, char *buf, size_t nbytes, const char **errsttr);
diff --git a/lib/iolog/iolog_nextid.c b/lib/iolog/iolog_nextid.c
index 5ca0ca691..8977a35f6 100644
--- a/lib/iolog/iolog_nextid.c
+++ b/lib/iolog/iolog_nextid.c
@@ -50,11 +50,12 @@
  * Uses file locking to avoid sequence number collisions.
  */
 bool
-iolog_nextid(char *iolog_dir, char sessid[7])
+iolog_nextid(const char *iolog_dir, char sessid[7])
 {
     char buf[32], *ep;
-    int i, len, fd = -1;
+    int i, fd = -1;
     unsigned long id = 0;
+    size_t len;
     ssize_t nread;
     bool ret = false;
     char pathbuf[PATH_MAX];
@@ -66,14 +67,21 @@ iolog_nextid(char *iolog_dir, char sessid[7])
     /*
      * Create I/O log directory if it doesn't already exist.
      */
-    if (!iolog_mkdirs(iolog_dir))
+    len = strlcpy(pathbuf, iolog_dir, sizeof(pathbuf));
+    if (len >= sizeof(pathbuf)) {
+	errno = ENAMETOOLONG;
+	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
+	    "%s: %s", __func__, iolog_dir);
+	goto done;
+    }
+    if (!iolog_mkdirs(pathbuf))
 	goto done;
 
     /*
      * Open sequence file
      */
-    len = snprintf(pathbuf, sizeof(pathbuf), "%s/seq", iolog_dir);
-    if (len < 0 || len >= ssizeof(pathbuf)) {
+    len = strlcat(pathbuf, "/seq", sizeof(pathbuf));
+    if (len >= sizeof(pathbuf)) {
 	errno = ENAMETOOLONG;
 	sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_ERRNO,
 	    "%s: %s/seq", __func__, iolog_dir);