[dm-devel] [PATCH V2 09/14] libmultipath: check whether mp->features is NUll in assemble_map

[lixiaokeng]

In assemble_map func, if add_feature fails and mp->features is
default value (NULL), STRDUP(mp->features) will cause a seg-fault.
In addition, f = STRDUP(mp->features) is just used for APPEND().
We can directly pass mp->features to APPEND().

Here, we firstly check whether mp->features is null.

V1->V2: use ?: instead of checking mp->features

Signed-off-by: Zhiqiang Liu <liuzhiqiang26 at huawei.com>
Signed-off-by: lixiaokeng <lixiaokeng at huawei.com>
---
 libmultipath/dmparser.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/libmultipath/dmparser.c b/libmultipath/dmparser.c
index 482e9d0e..3c5e016a 100644
--- a/libmultipath/dmparser.c
+++ b/libmultipath/dmparser.c
@@ -65,7 +65,7 @@ assemble_map (struct multipath * mp, char * params, int len)
        int i, j;
        int minio;
        int nr_priority_groups, initial_pg_nr;
-       char * p, * f;
+       char * p;
        const char *const end = params + len;
        char no_path_retry[] = "queue_if_no_path";
        char retain_hwhandler[] = "retain_attached_hw_handler";
@@ -86,10 +86,8 @@ assemble_map (struct multipath * mp, char * params, int len)
            get_linux_version_code() < KERNEL_VERSION(4, 3, 0))
                add_feature(&mp->features, retain_hwhandler);

-       f = STRDUP(mp->features);
-
-       APPEND(p, end, "%s %s %i %i", f, mp->hwhandler, nr_priority_groups,
-              initial_pg_nr);
+       APPEND(p, end, "%s %s %i %i", mp->features ? mp->features : 0, mp->hwhandler,
+               nr_priority_groups, initial_pg_nr);

        vector_foreach_slot (mp->pg, pgp, i) {
                pgp = VECTOR_SLOT(mp->pg, i);
@@ -110,12 +108,10 @@ assemble_map (struct multipath * mp, char * params, int len)
                }
        }

-       FREE(f);
        condlog(4, "%s: assembled map [%s]", mp->alias, params);
        return 0;

 err:
-       FREE(f);
        return 1;
 }

--