libzfsbootenv: lzbe_set_boot_device(): don't free undefined pointer

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #11993

diff --git a/lib/libzfsbootenv/lzbe_device.c b/lib/libzfsbootenv/lzbe_device.c
index b366bd9c7f57d987e50940a6c069d744af850139..2d8833b4fff29c82f32da10d78a991085826baf6 100644 (file)
--- a/lib/libzfsbootenv/lzbe_device.c
+++ b/lib/libzfsbootenv/lzbe_device.c
@@ -88,12 +88,11 @@ lzbe_set_boot_device(const char *pool, lzbe_flags_t flag, const char *device)
                if (strncmp(device, "zfs:", 4) == 0) {
                        fnvlist_add_string(nv, OS_BOOTONCE, device);
                } else {
-                       descriptor = NULL;
-                       if (asprintf(&descriptor, "zfs:%s:", device) > 0)
+                       if (asprintf(&descriptor, "zfs:%s:", device) > 0) {
                                fnvlist_add_string(nv, OS_BOOTONCE, descriptor);
-                       else
+                               free(descriptor);
+                       } else
                                rv = ENOMEM;
-                       free(descriptor);
                }
        }