master - coverity: check vg->lvm1_system_id is not NULL before calling strncmp with that

[Peter Rajnoha]

Gitweb:        http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=f02cdcff0084a323c...
Commit:        f02cdcff0084a323c9651d7ca2f22d60c83bcf3d
Parent:        1f3d04cddf5a447de9bfb81ed22d0ccbe58e82fc
Author:        Peter Rajnoha 
AuthorDate:    Tue Aug 4 10:16:45 2015 +0200
Committer:     Peter Rajnoha 
CommitterDate: Tue Aug 4 10:35:31 2015 +0200

coverity: check vg->lvm1_system_id is not NULL before calling strncmp with that

lib/format1/import-export.c:167: var_deref_model: Passing null pointer "vg->lvm1_system_id" to "strncmp", which dereferences it.
---
 lib/format1/import-export.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/lib/format1/import-export.c b/lib/format1/import-export.c
index 275583d..9e49a96 100644
--- a/lib/format1/import-export.c
+++ b/lib/format1/import-export.c
@@ -164,7 +164,7 @@ int export_pv(struct cmd_context *cmd, struct dm_pool *mem __attribute__((unused
    /* Is VG already exported or being exported? */
    if (vg && vg_is_exported(vg)) {
    	/* Does system_id need setting? */
-		if ((vg->lvm1_system_id && !*vg->lvm1_system_id) ||
+		if (!vg->lvm1_system_id || !*vg->lvm1_system_id ||
    	    strncmp(vg->lvm1_system_id, EXPORTED_TAG,
    		    sizeof(EXPORTED_TAG) - 1)) {
    		if (!generate_lvm1_system_id(cmd, (char *)pvd->system_id, EXPORTED_TAG))