[Libguestfs] [PATCH] daemon: blkid: fix memory issues in "no -p/-i" mode

[Pino Toscano]

Fix the memory issues in the implementation that uses no -p nor -i:
- use add_string_nodup to add results from get_blkid_tag (which returns
  new strings), so those strings are not leaked
- use free_stringslen to clean the hash on error, as in such case the
  stringbuf will not be terminated with a null entry, thus causing
  free_strings to crash
---
 daemon/blkid.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/daemon/blkid.c b/daemon/blkid.c
index 83ff355..b98c155 100644
--- a/daemon/blkid.c
+++ b/daemon/blkid.c
@@ -197,19 +197,19 @@ blkid_without_p_i_opt(const char *device)
   if (add_string (&ret, "TYPE") == -1) goto error;
   s = get_blkid_tag (device, "TYPE");
   if (s == NULL) goto error;
-  if (add_string (&ret, s) == -1)
+  if (add_string_nodup (&ret, s) == -1)
     goto error;
 
   if (add_string (&ret, "LABEL") == -1) goto error;
   s = get_blkid_tag (device, "LABEL");
   if (s == NULL) goto error;
-  if (add_string (&ret, s) == -1)
+  if (add_string_nodup (&ret, s) == -1)
     goto error;
 
   if (add_string (&ret, "UUID") == -1) goto error;
   s = get_blkid_tag (device, "UUID");
   if (s == NULL) goto error;
-  if (add_string (&ret, s) == -1)
+  if (add_string_nodup (&ret, s) == -1)
     goto error;
 
   if (end_stringsbuf (&ret) == -1) goto error;
@@ -217,7 +217,7 @@ blkid_without_p_i_opt(const char *device)
   return ret.argv;
 error:
   if (ret.argv)
-    free_strings (ret.argv);
+    free_stringslen (ret.argv, ret.size);
   return NULL;
 }
 
-- 
1.9.3