From: Luca Boccassi <luca.boccassi@microsoft.com>
Date: Wed, 17 Mar 2021 14:34:36 +0000 (+0000)
Subject: resolved: simplify min_ttl check
X-Git-Tag: v248-rc4~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18da93648169f9bbf48a979031bd634c4bee7e95;p=thirdparty%2Fsystemd.git

resolved: simplify min_ttl check

rr is asserted upon a few lines above, no need to check for null.
Coverity-found issue, CID 1450844

  CID 1450844:  Null pointer dereferences  (REVERSE_INULL)
  Null-checking "rr" suggests that it may be null, but it has already
    been dereferenced on all paths leading to the check.
---

diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c
index 9b2e7115c0a..c019dc38c9d 100644
--- a/src/resolve/resolved-dns-cache.c
+++ b/src/resolve/resolved-dns-cache.c
@@ -439,9 +439,7 @@ static int dns_cache_put_positive(
         /* Determine the minimal TTL of all RRs in the answer plus the one by the main RR we are supposed to
          * cache. Since we cache whole answers to questions we should never return answers where only some
          * RRs are still valid, hence find the lowest here */
-        min_ttl = dns_answer_min_ttl(answer);
-        if (rr)
-                min_ttl = MIN(min_ttl, rr->ttl);
+        min_ttl = MIN(dns_answer_min_ttl(answer), rr->ttl);
 
         /* New TTL is 0? Delete this specific entry... */
         if (min_ttl <= 0) {