app-emulation/spice/files/spice-0.14.3-CVE-2020-14355-b24fe6b6.patch


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diff --git a/common/quic_family_tmpl.c b/common/quic_family_tmpl.c
index 8a5f7d2c9be3f6b1bd82993703749268bab243b4..6cc051b36889f773fe5401e204db6245d99e27df 100644
--- a/subprojects/spice-common/common/quic_family_tmpl.c
+++ b/subprojects/spice-common/common/quic_family_tmpl.c
@@ -103,7 +103,12 @@ static s_bucket *FNAME(find_bucket)(Channel *channel, const unsigned int val)
 {
     spice_extra_assert(val < (0x1U << BPC));
 
-    return channel->_buckets_ptrs[val];
+    /* The and (&) here is to avoid buffer overflows in case of garbage or malicious
+     * attempts. Is much faster then using comparisons and save us from such situations.
+     * Note that on normal build the check above won't be compiled as this code path
+     * is pretty hot and would cause speed regressions.
+     */
+    return channel->_buckets_ptrs[val & ((1U << BPC) - 1)];
 }
 
 #undef FNAME