Move the original log_info call out of the core of buf_shrink_freelists.

Sending a log message to a control port can cause Tor to allocate a buffer,
thereby changing the length of the freelist behind buf_shrink_freelists's back,
thereby causing an assertion to fail.

Fixes bug #1125.

1 files changed, 5 insertions, 5 deletions

diff --git a/src/or/buffers.c b/src/or/buffers.c
index 09ccb7cb0..e835c615e 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -269,16 +269,12 @@ buf_shrink_freelists(int free_all)
       int n_to_free = free_all ? freelists[i].cur_length :
         (freelists[i].lowest_length - slack);
       int n_to_skip = freelists[i].cur_length - n_to_free;
+      int orig_length = freelists[i].cur_length;
       int orig_n_to_free = n_to_free, n_freed=0;
       int orig_n_to_skip = n_to_skip;
       int new_length = n_to_skip;
       chunk_t **chp = &freelists[i].head;
       chunk_t *chunk;
-      log_info(LD_MM, "Cleaning freelist for %d-byte chunks: length %d, "
-               "keeping %d, dropping %d.",
-               (int)freelists[i].alloc_size, freelists[i].cur_length,
-               n_to_skip, n_to_free);
-      tor_assert(n_to_skip + n_to_free == freelists[i].cur_length);
       while (n_to_skip) {
         if (! (*chp)->next) {
           log_warn(LD_BUG, "I wanted to skip %d chunks in the freelist for "
@@ -313,6 +309,10 @@ buf_shrink_freelists(int free_all)
       }
       // tor_assert(!n_to_free);
       freelists[i].cur_length = new_length;
+      log_info(LD_MM, "Cleaned freelist for %d-byte chunks: original "
+               "length %d, kept %d, dropped %d.",
+               (int)freelists[i].alloc_size, orig_length,
+               orig_n_to_skip, orig_n_to_free);
     }
     freelists[i].lowest_length = freelists[i].cur_length;
     assert_freelist_ok(&freelists[i]);