[fedfs-utils] [PATCH fedfs-utils] nfsref: fix a segmentation fault when lookup a junction

[Ditang Chen]

Can not retrieve FSN with the fsn_uuid when lookup a junction,the entries 
is 1 and the 'tmp' pointer to NULL.

# ls -l
total 8
d--------T 2 root root 4096 Jun  4 07:05 s2
# nsdb-list 
NSDB: ldap.example.net:389
  NCE ou=fedfs,dc=example,dc=net has no FSN records
# nfsref lookup s2
Segmentation fault

(gdb) bt
#0  0x0000000000404eb0 in nfsref_lookup_resolve_fsn (host=0x118d630, fsn_uuid=<optimized out>) at lookup.c:364
#1  nfsref_lookup_nfs_fedfs (junct_path=<optimized out>) at lookup.c:483
#2  0x0000000000403cf9 in main (argc=3, argv=0x7fff69dea5e8) at nfsref.c:181

Signed-off-by: chendt.fnst at cn.fujitsu.com
---
 src/libnsdb/fileserver.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/libnsdb/fileserver.c b/src/libnsdb/fileserver.c
index 965f1a1..0899f00 100644
--- a/src/libnsdb/fileserver.c
+++ b/src/libnsdb/fileserver.c
@@ -1527,8 +1527,14 @@ nsdb_get_fsn_find_entry_s(nsdb_t host, const char *nce, const char *fsn_uuid,
 	ldap_msgfree(response);
 
 	if (retval == FEDFS_OK) {
-		xlog(D_CALL, "%s: returning fsn", __func__);
-		*fsn = tmp;
+		if (tmp == NULL) {
+			xlog(D_CALL, "%s: No FSN entries for FSN UUID %s",
+				__func__, fsn_uuid);
+			retval = FEDFS_ERR_NSDB_NOFSN;
+		} else {
+			xlog(D_CALL, "%s: returning fsn", __func__);
+			*fsn = tmp;
+		}
 	} else
 		nsdb_free_fedfs_fsn(tmp);
 	return retval;
-- 
1.8.4.2