Hi,
Here is another access to uninitialized values detected by valgrind. The
function CacheFlush() (cache.c:335) initializes
entries[k].nd_{primary,secondary}.nEvalContext and entries[k].lock, but keys
are not initialized.
When the eval cache is almost empty (e.g., at the startup),
CacheLookupNoLocking() and CacheLookupWithLocking () accesses keys, which may
be uninitialized, before checking nEvalContext.
Below patch swaps the order of condition check.
Thank you very much.
Regards,
Daisuke Takahashi
--- lib/cache.c 16 Jun 2013 02:16:23 -0000 1.35
+++ lib/cache.c 14 Jul 2014 14:43:46 -0000
@@ -247,8 +247,8 @@
#if USE_MULTITHREAD
cache_lock(pc, l);
#endif
- if (!EqualKeys(pc->entries[l].nd_primary.key, e->key) ||
pc->entries[l].nd_primary.nEvalContext != e->nEvalContext) { /* Not in
primary slot */
- if (!EqualKeys(pc->entries[l].nd_secondary.key, e->key) ||
pc->entries[l].nd_secondary.nEvalContext != e->nEvalContext) { /* Cache
miss */
+ if (pc->entries[l].nd_primary.nEvalContext != e->nEvalContext ||
!EqualKeys(pc->entries[l].nd_primary.key, e->key)) { /* Not in primary
slot */
+ if (pc->entries[l].nd_secondary.nEvalContext != e->nEvalContext ||
!EqualKeys(pc->entries[l].nd_secondary.key, e->key)) { /* Cache miss */
#if USE_MULTITHREAD
cache_unlock(pc, l);
#endif
@@ -284,8 +284,8 @@
#if CACHE_STATS
++pc->cLookup;
#endif
- if (!EqualKeys(pc->entries[l].nd_primary.key, e->key) ||
pc->entries[l].nd_primary.nEvalContext != e->nEvalContext) { /* Not in
primary slot */
- if (!EqualKeys(pc->entries[l].nd_secondary.key, e->key) ||
pc->entries[l].nd_secondary.nEvalContext != e->nEvalContext) { /* Cache
miss */
+ if (pc->entries[l].nd_primary.nEvalContext != e->nEvalContext ||
!EqualKeys(pc->entries[l].nd_primary.key, e->key)) { /* Not in primary
slot */
+ if (pc->entries[l].nd_secondary.nEvalContext != e->nEvalContext ||
!EqualKeys(pc->entries[l].nd_secondary.key, e->key)) { /* Cache miss */
return l;
} else { /* Found in second slot, promote "hot" entry */
cacheNodeDetail tmp = pc->entries[l].nd_primary;
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