From: Nick Mathewson <nickm@torproject.org>
Date: Sat, 19 Apr 2014 00:28:46 +0000 (-0400)
Subject: scan-build: check impossible null-pointer case in buffers.c
X-Git-Tag: tor-0.2.5.4-alpha~14^2~17
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=41a8930fa1202b882687c0c3a328307b480934b5;p=thirdparty%2Ftor.git

scan-build: check impossible null-pointer case in buffers.c

When maintaining buffer freelists, we don't skip more than there
are, so (*chp) can't be null to begin with.  scan-build has no way
to know that.
---

diff --git a/src/or/buffers.c b/src/or/buffers.c
index 012ced6d32..fb186081cf 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -322,7 +322,7 @@ buf_shrink_freelists(int free_all)
       chunk_t **chp = &freelists[i].head;
       chunk_t *chunk;
       while (n_to_skip) {
-        if (! (*chp)->next) {
+        if (!(*chp) || ! (*chp)->next) {
           log_warn(LD_BUG, "I wanted to skip %d chunks in the freelist for "
                    "%d-byte chunks, but only found %d. (Length %d)",
                    orig_n_to_skip, (int)freelists[i].alloc_size,