socket-util: fix getpeergroups() assert(fd) (#8080)

Don't assert on zero-value fds.

Fixes #8075.

(cherry picked from commit 75f40779607ea79f20441c7fb46744d04ee2c7ae)

diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index d89136b01f7a373a2ec0742b6b374a5e689645f8..007b302e721acee91f8f2543d33082037981662c 100644 (file)
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -1036,7 +1036,7 @@ int getpeergroups(int fd, gid_t **ret) {
         socklen_t n = sizeof(gid_t) * 64;
         _cleanup_free_ gid_t *d = NULL;
 
-        assert(fd);
+        assert(fd >= 0);
         assert(ret);
 
         for (;;) {