git: 88d94ead7f7c - main - lposix: Use reentrant passwd and group lookup functions

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=88d94ead7f7cfb7ea7c4134b4cd2f89da670a8e1

commit 88d94ead7f7cfb7ea7c4134b4cd2f89da670a8e1
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-07-04 19:06:10 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2025-07-04 20:11:12 +0000

    lposix: Use reentrant passwd and group lookup functions
    
    The implementation of chown() in the posix module handles user and group
    names as well as numeric IDs.  When resolving names, be sure to use
    reentrant lookup functions rather than assuming it's safe to clobber the
    internal buffers used by getpwnam() and getgrnam().
    
    Fix some style nits while here.
    
    Reviewed by:    imp, bapt
    MFC after:      2 weeks
    Differential Revision:  https://reviews.freebsd.org/D46555
---
 libexec/flua/modules/lposix.c | 29 +++++++++++++++++++----------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/libexec/flua/modules/lposix.c b/libexec/flua/modules/lposix.c
index 816d4bc688d2..9edc7e687786 100644
--- a/libexec/flua/modules/lposix.c
+++ b/libexec/flua/modules/lposix.c
@@ -88,18 +88,23 @@ static int
 lua_chown(lua_State *L)
 {
 	const char *path;
-	uid_t owner = (uid_t) -1;
-	gid_t group = (gid_t) -1;
+	uid_t owner = (uid_t)-1;
+	gid_t group = (gid_t)-1;
+	int error;
 
 	enforce_max_args(L, 3);
 
 	path = luaL_checkstring(L, 1);
 	if (lua_isinteger(L, 2))
-		owner = (uid_t) lua_tointeger(L, 2);
+		owner = (uid_t)lua_tointeger(L, 2);
 	else if (lua_isstring(L, 2)) {
-		struct passwd *p = getpwnam(lua_tostring(L, 2));
-		if (p != NULL)
-			owner = p->pw_uid;
+		char buf[4096];
+		struct passwd passwd, *pwd;
+
+		error = getpwnam_r(lua_tostring(L, 2), &passwd,
+		    buf, sizeof(buf), &pwd);
+		if (error == 0)
+			owner = pwd->pw_uid;
 		else
 			return (luaL_argerror(L, 2,
 			    lua_pushfstring(L, "unknown user %s",
@@ -112,11 +117,15 @@ lua_chown(lua_State *L)
 	}
 
 	if (lua_isinteger(L, 3))
-		group = (gid_t) lua_tointeger(L, 3);
+		group = (gid_t)lua_tointeger(L, 3);
 	else if (lua_isstring(L, 3)) {
-		struct group *g = getgrnam(lua_tostring(L, 3));
-		if (g != NULL)
-			group = g->gr_gid;
+		char buf[4096];
+		struct group gr, *grp;
+
+		error = getgrnam_r(lua_tostring(L, 3), &gr, buf, sizeof(buf),
+		    &grp);
+		if (error == 0)
+			group = grp->gr_gid;
 		else
 			return (luaL_argerror(L, 3,
 			    lua_pushfstring(L, "unknown group %s",