[Libguestfs] [PATCH nbdkit nbd] nbd: Unsuccessful attempt to fix memory leak.

[Richard W.M. Jones]

==20307==
==20307== HEAP SUMMARY:
==20307==     in use at exit: 2,267 bytes in 23 blocks
==20307==   total heap usage: 2,298 allocs, 2,275 frees, 307,606 bytes allocated
==20307==
==20307== 96 bytes in 3 blocks are definitely lost in loss record 4 of 10
==20307==    at 0x4C2FA1E: calloc (vg_replace_malloc.c:711)
==20307==    by 0x77EBBAF: ???
==20307==    by 0x77EBD17: ???
==20307==    by 0x40595C: handle_request (connections.c:894)
==20307==    by 0x40595C: recv_request_send_reply (connections.c:1061)
==20307==    by 0x405AE7: connection_worker (connections.c:200)
==20307==    by 0x55DC55A: start_thread (in /usr/lib64/libpthread-2.26.9000.so)
==20307==    by 0x58E85AE: clone (in /usr/lib64/libc-2.26.9000.so)
==20307==
==20307== 320 bytes in 10 blocks are definitely lost in loss record 9 of 10
==20307==    at 0x4C2FA1E: calloc (vg_replace_malloc.c:711)
==20307==    by 0x77EBBAF: ???
==20307==    by 0x77EBD98: ???
==20307==    by 0x405986: handle_request (connections.c:884)
==20307==    by 0x405986: recv_request_send_reply (connections.c:1061)
==20307==    by 0x405AE7: connection_worker (connections.c:200)
==20307==    by 0x55DC55A: start_thread (in /usr/lib64/libpthread-2.26.9000.so)
==20307==    by 0x58E85AE: clone (in /usr/lib64/libc-2.26.9000.so)
==20307==
==20307== LEAK SUMMARY:
==20307==    definitely lost: 416 bytes in 13 blocks
==20307==    indirectly lost: 0 bytes in 0 blocks
==20307==      possibly lost: 0 bytes in 0 blocks
==20307==    still reachable: 411 bytes in 5 blocks
==20307==         suppressed: 1,440 bytes in 5 blocks
==20307== Reachable blocks (those to which a pointer was found) are not shown.
==20307== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==20307==
==20307== For counts of detected and suppressed errors, rerun with: -v
==20307== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 3 from 3)
---
 plugins/nbd/nbd.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/plugins/nbd/nbd.c b/plugins/nbd/nbd.c
index b844bf5..4f5e027 100644
--- a/plugins/nbd/nbd.c
+++ b/plugins/nbd/nbd.c
@@ -536,6 +536,7 @@ static void
 nbd_close (void *handle)
 {
   struct handle *h = handle;
+  struct transaction *trans, *trans_next;
 
   if (!h->dead)
     nbd_request_raw (h, NBD_CMD_DISC, 0, 0, 0, NULL);
@@ -544,6 +545,10 @@ nbd_close (void *handle)
     nbdkit_debug ("failed to join reader thread: %m");
   pthread_mutex_destroy (&h->write_lock);
   pthread_mutex_destroy (&h->trans_lock);
+  for (trans = h->trans; trans != NULL; trans = trans_next) {
+    trans_next = trans->next;
+    free (trans);
+  }
   free (h);
 }
 
-- 
2.13.2