From bce18c91638e9f37ef2c37555cbb41a0f1f98ab0 Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Mon, 8 Sep 2014 18:09:43 +0900 Subject: [PATCH] When comparing DNS server configs, also compare number of servers Bug: 16070602 Change-Id: I605f1cca50b08479ebcad290b3bd179f59be8a96 --- libc/dns/resolv/res_cache.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/libc/dns/resolv/res_cache.c b/libc/dns/resolv/res_cache.c index 77a1b4d19..6f1fcd356 100644 --- a/libc/dns/resolv/res_cache.c +++ b/libc/dns/resolv/res_cache.c @@ -1965,10 +1965,25 @@ _resolv_is_nameservers_equal_locked(struct resolv_cache_info* cache_info, { int i; char** ns; + int currentservers; int equal = 1; - // compare each name server against current name servers if (numservers > MAXNS) numservers = MAXNS; + + // Find out how many nameservers we had before. + currentservers = 0; + for (ns = cache_info->nameservers; *ns; ns++) + currentservers++; + + if (currentservers != numservers) + return 0; + + // Compare each name server against current name servers. + // TODO: this is incorrect if the list of current or previous nameservers + // contains duplicates. This does not really matter because the framework + // filters out duplicates, but we should probably fix it. It's also + // insensitive to the order of the nameservers; we should probably fix that + // too. for (i = 0; i < numservers && equal; i++) { ns = cache_info->nameservers; equal = 0;