From e0d71ef6398d571d170eee18e1daad2ac81040d8 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 14:18:41 +0200
Subject: [PATCH 01/17] removed obsolete ArrayList usage

---
 lib/std/net.zig | 77 +++++++++++++++++++++++++++----------------------
 1 file changed, 42 insertions(+), 35 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 37fe2734d52d..7054602d06fe 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1591,16 +1591,14 @@ const ResolvConf = struct {
     ndots: u32,
     timeout: u32,
     search: ArrayList(u8),
-    /// TODO there are actually only allowed to be maximum 3 nameservers, no need
-    /// for an array list.
-    ns: ArrayList(LookupAddr),
+    ns: [3]?LookupAddr,
 
     /// Returns `error.StreamTooLong` if a line is longer than 512 bytes.
     /// TODO: https://github.com/ziglang/zig/issues/2765 and https://github.com/ziglang/zig/issues/2761
     fn init(rc: *ResolvConf, gpa: Allocator) !void {
         rc.* = .{
             .gpa = gpa,
-            .ns = .empty,
+            .ns = .{ null, null, null },
             .search = .empty,
             .ndots = 1,
             .timeout = 5,
@@ -1612,7 +1610,7 @@ const ResolvConf = struct {
             error.FileNotFound,
             error.NotDir,
             error.AccessDenied,
-            => return linuxLookupNameFromNumericUnspec(gpa, &rc.ns, "127.0.0.1", 53),
+            => return linuxLookupNameFromNumericUnspec(&rc.ns, "127.0.0.1", 53),
             else => |e| return e,
         };
         defer file.close();
@@ -1655,7 +1653,7 @@ const ResolvConf = struct {
                 },
                 .nameserver => {
                     const ip_txt = line_it.next() orelse continue;
-                    try linuxLookupNameFromNumericUnspec(gpa, &rc.ns, ip_txt, 53);
+                    try linuxLookupNameFromNumericUnspec(&rc.ns, ip_txt, 53);
                 },
                 .domain, .search => {
                     rc.search.items.len = 0;
@@ -1667,8 +1665,8 @@ const ResolvConf = struct {
             else => |e| return e,
         }
 
-        if (rc.ns.items.len == 0) {
-            return linuxLookupNameFromNumericUnspec(gpa, &rc.ns, "127.0.0.1", 53);
+        if (&rc.ns == &[3]?LookupAddr{ null, null, null }) {
+            return linuxLookupNameFromNumericUnspec(&rc.ns, "127.0.0.1", 53);
         }
     }
 
@@ -1678,23 +1676,21 @@ const ResolvConf = struct {
         answers: [][]u8,
         answer_bufs: []const []u8,
     ) !void {
-        const gpa = rc.gpa;
         const timeout = 1000 * rc.timeout;
         const attempts = rc.attempts;
 
         var sl: posix.socklen_t = @sizeOf(posix.sockaddr.in);
         var family: posix.sa_family_t = posix.AF.INET;
 
-        var ns_list: ArrayList(Address) = .empty;
-        defer ns_list.deinit(gpa);
-
-        try ns_list.resize(gpa, rc.ns.items.len);
+        var ns_arr: [3]?Address = .{ null, null, null };
 
-        for (ns_list.items, rc.ns.items) |*ns, iplit| {
-            ns.* = iplit.addr;
-            assert(ns.getPort() == 53);
-            if (iplit.addr.any.family != posix.AF.INET) {
-                family = posix.AF.INET6;
+        for (&ns_arr, rc.ns) |*ns, iplit| {
+            if (iplit) |ip| {
+                ns.* = ip.addr;
+                assert(ns.*.?.getPort() == 53);
+                if (ip.addr.any.family != posix.AF.INET) {
+                    family = posix.AF.INET6;
+                }
             }
         }
 
@@ -1724,13 +1720,15 @@ const ResolvConf = struct {
                 std.os.linux.IPV6.V6ONLY,
                 &mem.toBytes(@as(c_int, 0)),
             );
-            for (ns_list.items) |*ns| {
-                if (ns.any.family != posix.AF.INET) continue;
-                mem.writeInt(u32, ns.in6.sa.addr[12..], ns.in.sa.addr, native_endian);
-                ns.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
-                ns.any.family = posix.AF.INET6;
-                ns.in6.sa.flowinfo = 0;
-                ns.in6.sa.scope_id = 0;
+            for (&ns_arr) |*ns| {
+                if (ns.*) |*n| {
+                    if (n.*.any.family != posix.AF.INET) continue;
+                    mem.writeInt(u32, n.*.in6.sa.addr[12..], n.*.in.sa.addr, native_endian);
+                    n.*.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
+                    n.*.any.family = posix.AF.INET6;
+                    n.*.in6.sa.flowinfo = 0;
+                    n.*.in6.sa.scope_id = 0;
+                }
             }
             sl = @sizeOf(posix.sockaddr.in6);
         }
@@ -1760,8 +1758,10 @@ const ResolvConf = struct {
                 var i: usize = 0;
                 while (i < queries.len) : (i += 1) {
                     if (answers[i].len == 0) {
-                        for (ns_list.items) |*ns| {
-                            _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
+                        for (&ns_arr) |*ns| {
+                            if (ns.*) |*n| {
+                                _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &n.any, sl) catch undefined;
+                            }
                         }
                     }
                 }
@@ -1782,8 +1782,10 @@ const ResolvConf = struct {
                 if (rlen < 4) continue;
 
                 // Ignore replies from addresses we didn't send to
-                const ns = for (ns_list.items) |*ns| {
-                    if (ns.eql(sa)) break ns;
+                const ns = for (ns_arr) |ns| {
+                    if (ns) |n| {
+                        if (n.eql(sa)) break ns;
+                    }
                 } else continue;
 
                 // Find which query this answer goes with, if any
@@ -1802,7 +1804,7 @@ const ResolvConf = struct {
                     0, 3 => {},
                     2 => if (servfail_retry != 0) {
                         servfail_retry -= 1;
-                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
+                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.?.any, sl) catch undefined;
                     },
                     else => continue,
                 }
@@ -1823,20 +1825,25 @@ const ResolvConf = struct {
 
     fn deinit(rc: *ResolvConf) void {
         const gpa = rc.gpa;
-        rc.ns.deinit(gpa);
         rc.search.deinit(gpa);
         rc.* = undefined;
     }
 };
 
 fn linuxLookupNameFromNumericUnspec(
-    gpa: Allocator,
-    addrs: *ArrayList(LookupAddr),
+    addrs: *[3]?LookupAddr,
     name: []const u8,
     port: u16,
 ) !void {
-    const addr = try Address.resolveIp(name, port);
-    try addrs.append(gpa, .{ .addr = addr });
+    const address = try Address.resolveIp(name, port);
+    for (addrs) |*addr| {
+        if (addr.* == null) {
+            addr.* = .{ .addr = address };
+            return;
+        }
+    }
+
+    return error.OutOfMemory;
 }
 
 fn dnsParse(

From d82ea101f677a36a3f47b50aae757bfb3cdbaee4 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 14:52:36 +0200
Subject: [PATCH 02/17] remove unneeded eql check

---
 lib/std/net.zig | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 7054602d06fe..11d3dc9020d9 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1665,9 +1665,11 @@ const ResolvConf = struct {
             else => |e| return e,
         }
 
-        if (&rc.ns == &[3]?LookupAddr{ null, null, null }) {
-            return linuxLookupNameFromNumericUnspec(&rc.ns, "127.0.0.1", 53);
+        for (rc.ns) |n| {
+            if (n != null) return;
         }
+
+        return linuxLookupNameFromNumericUnspec(&rc.ns, "127.0.0.1", 53);
     }
 
     fn resMSendRc(

From 3d352c9f8b1c67014230ea178b683993ed5e9339 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 15:04:50 +0200
Subject: [PATCH 03/17] remove uneeded optional

---
 lib/std/net.zig | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 11d3dc9020d9..87764dbd4650 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1786,7 +1786,7 @@ const ResolvConf = struct {
                 // Ignore replies from addresses we didn't send to
                 const ns = for (ns_arr) |ns| {
                     if (ns) |n| {
-                        if (n.eql(sa)) break ns;
+                        if (n.eql(sa)) break n;
                     }
                 } else continue;
 
@@ -1806,7 +1806,7 @@ const ResolvConf = struct {
                     0, 3 => {},
                     2 => if (servfail_retry != 0) {
                         servfail_retry -= 1;
-                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.?.any, sl) catch undefined;
+                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
                     },
                     else => continue,
                 }

From 0bc3aaaaa88a157b3ca6f13de0599f7d77c1b363 Mon Sep 17 00:00:00 2001
From: usebeforefree <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 16:38:38 +0000
Subject: [PATCH 04/17] Update lib/std/net.zig
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Андрей Краевский <75577902+AndrewKraevskii@users.noreply.github.com>
---
 lib/std/net.zig | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 87764dbd4650..55219c8d0170 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1724,12 +1724,12 @@ const ResolvConf = struct {
             );
             for (&ns_arr) |*ns| {
                 if (ns.*) |*n| {
-                    if (n.*.any.family != posix.AF.INET) continue;
-                    mem.writeInt(u32, n.*.in6.sa.addr[12..], n.*.in.sa.addr, native_endian);
-                    n.*.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
-                    n.*.any.family = posix.AF.INET6;
-                    n.*.in6.sa.flowinfo = 0;
-                    n.*.in6.sa.scope_id = 0;
+                    if (n.any.family != posix.AF.INET) continue;
+                    mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
+                    n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
+                    n.any.family = posix.AF.INET6;
+                    n.in6.sa.flowinfo = 0;
+                    n.in6.sa.scope_id = 0;
                 }
             }
             sl = @sizeOf(posix.sockaddr.in6);

From 9533276caaf3f4ba2c73b3dc249a299038262b18 Mon Sep 17 00:00:00 2001
From: usebeforefree <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 16:39:21 +0000
Subject: [PATCH 05/17] Update lib/std/net.zig
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Андрей Краевский <75577902+AndrewKraevskii@users.noreply.github.com>
---
 lib/std/net.zig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 55219c8d0170..a8b345356e9a 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1595,7 +1595,7 @@ const ResolvConf = struct {
 
     /// Returns `error.StreamTooLong` if a line is longer than 512 bytes.
     /// TODO: https://github.com/ziglang/zig/issues/2765 and https://github.com/ziglang/zig/issues/2761
-    fn init(rc: *ResolvConf, gpa: Allocator) !void {
+    fn init(rc: *ResolvConf) !void {
         rc.* = .{
             .gpa = gpa,
             .ns = .{ null, null, null },

From c0e07045f9c6f036cc141d8e875b101cc94b6e80 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 18:51:46 +0200
Subject: [PATCH 06/17] move gpa out of ResolvConf struct

---
 lib/std/net.zig | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index a8b345356e9a..d80257bd03b7 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1483,7 +1483,7 @@ fn linuxLookupNameFromDnsSearch(
 ) !void {
     var rc: ResolvConf = undefined;
     rc.init(gpa) catch return error.ResolveConfParseFailed;
-    defer rc.deinit();
+    defer rc.deinit(gpa);
 
     // Count dots, suppress search when >=ndots or name ends in
     // a dot, which is an explicit request for global scope.
@@ -1586,7 +1586,6 @@ fn linuxLookupNameFromDns(
 }
 
 const ResolvConf = struct {
-    gpa: Allocator,
     attempts: u32,
     ndots: u32,
     timeout: u32,
@@ -1595,16 +1594,15 @@ const ResolvConf = struct {
 
     /// Returns `error.StreamTooLong` if a line is longer than 512 bytes.
     /// TODO: https://github.com/ziglang/zig/issues/2765 and https://github.com/ziglang/zig/issues/2761
-    fn init(rc: *ResolvConf) !void {
+    fn init(rc: *ResolvConf, gpa: Allocator) !void {
         rc.* = .{
-            .gpa = gpa,
             .ns = .{ null, null, null },
             .search = .empty,
             .ndots = 1,
             .timeout = 5,
             .attempts = 2,
         };
-        errdefer rc.deinit();
+        errdefer rc.deinit(gpa);
 
         const file = fs.openFileAbsoluteZ("/etc/resolv.conf", .{}) catch |err| switch (err) {
             error.FileNotFound,
@@ -1617,7 +1615,7 @@ const ResolvConf = struct {
 
         var line_buf: [512]u8 = undefined;
         var file_reader = file.reader(&line_buf);
-        return parse(rc, &file_reader.interface) catch |err| switch (err) {
+        return parse(rc, gpa, &file_reader.interface) catch |err| switch (err) {
             error.ReadFailed => return file_reader.err.?,
             else => |e| return e,
         };
@@ -1626,8 +1624,7 @@ const ResolvConf = struct {
     const Directive = enum { options, nameserver, domain, search };
     const Option = enum { ndots, attempts, timeout };
 
-    fn parse(rc: *ResolvConf, reader: *Io.Reader) !void {
-        const gpa = rc.gpa;
+    fn parse(rc: *ResolvConf, gpa: Allocator, reader: *Io.Reader) !void {
         while (reader.takeSentinel('\n')) |line_with_comment| {
             const line = line: {
                 var split = mem.splitScalar(u8, line_with_comment, '#');
@@ -1825,8 +1822,7 @@ const ResolvConf = struct {
         }
     }
 
-    fn deinit(rc: *ResolvConf) void {
-        const gpa = rc.gpa;
+    fn deinit(rc: *ResolvConf, gpa: Allocator) void {
         rc.search.deinit(gpa);
         rc.* = undefined;
     }

From feea90e225afacfc9df0c0d7ed5cab90b281b758 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 20:59:08 +0200
Subject: [PATCH 07/17] make ns a buffer

---
 lib/std/net.zig | 46 +++++++++++++++++++++-------------------------
 1 file changed, 21 insertions(+), 25 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index d80257bd03b7..28066e4728fc 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1590,13 +1590,15 @@ const ResolvConf = struct {
     ndots: u32,
     timeout: u32,
     search: ArrayList(u8),
-    ns: [3]?LookupAddr,
+    ns_buffer: [3]LookupAddr,
+    ns_len: u2,
 
     /// Returns `error.StreamTooLong` if a line is longer than 512 bytes.
     /// TODO: https://github.com/ziglang/zig/issues/2765 and https://github.com/ziglang/zig/issues/2761
     fn init(rc: *ResolvConf, gpa: Allocator) !void {
         rc.* = .{
-            .ns = .{ null, null, null },
+            .ns_buffer = undefined,
+            .ns_len = 0,
             .search = .empty,
             .ndots = 1,
             .timeout = 5,
@@ -1608,7 +1610,7 @@ const ResolvConf = struct {
             error.FileNotFound,
             error.NotDir,
             error.AccessDenied,
-            => return linuxLookupNameFromNumericUnspec(&rc.ns, "127.0.0.1", 53),
+            => return linuxLookupNameFromNumericUnspec(&rc.ns_buffer, &rc.ns_len, "127.0.0.1", 53),
             else => |e| return e,
         };
         defer file.close();
@@ -1650,7 +1652,7 @@ const ResolvConf = struct {
                 },
                 .nameserver => {
                     const ip_txt = line_it.next() orelse continue;
-                    try linuxLookupNameFromNumericUnspec(&rc.ns, ip_txt, 53);
+                    try linuxLookupNameFromNumericUnspec(&rc.ns_buffer, &rc.ns_len, ip_txt, 53);
                 },
                 .domain, .search => {
                     rc.search.items.len = 0;
@@ -1662,11 +1664,9 @@ const ResolvConf = struct {
             else => |e| return e,
         }
 
-        for (rc.ns) |n| {
-            if (n != null) return;
+        if (rc.ns_len == 0) {
+            return linuxLookupNameFromNumericUnspec(&rc.ns_buffer, &rc.ns_len, "127.0.0.1", 53);
         }
-
-        return linuxLookupNameFromNumericUnspec(&rc.ns, "127.0.0.1", 53);
     }
 
     fn resMSendRc(
@@ -1681,15 +1681,14 @@ const ResolvConf = struct {
         var sl: posix.socklen_t = @sizeOf(posix.sockaddr.in);
         var family: posix.sa_family_t = posix.AF.INET;
 
-        var ns_arr: [3]?Address = .{ null, null, null };
+        var ns_arr: [3]Address = .{ null, null, null };
 
-        for (&ns_arr, rc.ns) |*ns, iplit| {
-            if (iplit) |ip| {
-                ns.* = ip.addr;
-                assert(ns.*.?.getPort() == 53);
-                if (ip.addr.any.family != posix.AF.INET) {
-                    family = posix.AF.INET6;
-                }
+        for (0..rc.ns_len) |index| {
+            const ip = rc.ns_buffer[index];
+            ns_arr[index] = ip.addr;
+            assert(ns_arr[index].?.getPort() == 53);
+            if (ip.addr.any.family != posix.AF.INET) {
+                family = posix.AF.INET6;
             }
         }
 
@@ -1829,19 +1828,16 @@ const ResolvConf = struct {
 };
 
 fn linuxLookupNameFromNumericUnspec(
-    addrs: *[3]?LookupAddr,
+    addrs: *[3]LookupAddr,
+    addrs_len: *u2,
     name: []const u8,
     port: u16,
 ) !void {
-    const address = try Address.resolveIp(name, port);
-    for (addrs) |*addr| {
-        if (addr.* == null) {
-            addr.* = .{ .addr = address };
-            return;
-        }
-    }
+    if (addrs_len.* >= addrs.len - 1) return error.OutOfMemory;
 
-    return error.OutOfMemory;
+    const address = try Address.resolveIp(name, port);
+    addrs[addrs_len.*] = .{ .addr = address };
+    addrs_len.* += 1;
 }
 
 fn dnsParse(

From f6eff776c647f7ddb3b8c55e936ec5387646815b Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 21:32:47 +0200
Subject: [PATCH 08/17] made ns_arr a buffer

---
 lib/std/net.zig | 37 +++++++++++++++++--------------------
 1 file changed, 17 insertions(+), 20 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 28066e4728fc..634eb5d177b8 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1681,12 +1681,12 @@ const ResolvConf = struct {
         var sl: posix.socklen_t = @sizeOf(posix.sockaddr.in);
         var family: posix.sa_family_t = posix.AF.INET;
 
-        var ns_arr: [3]Address = .{ null, null, null };
+        var ns_buffer: [3]Address = undefined;
 
         for (0..rc.ns_len) |index| {
             const ip = rc.ns_buffer[index];
-            ns_arr[index] = ip.addr;
-            assert(ns_arr[index].?.getPort() == 53);
+            ns_buffer[index] = ip.addr;
+            assert(ns_buffer[index].getPort() == 53);
             if (ip.addr.any.family != posix.AF.INET) {
                 family = posix.AF.INET6;
             }
@@ -1718,15 +1718,14 @@ const ResolvConf = struct {
                 std.os.linux.IPV6.V6ONLY,
                 &mem.toBytes(@as(c_int, 0)),
             );
-            for (&ns_arr) |*ns| {
-                if (ns.*) |*n| {
-                    if (n.any.family != posix.AF.INET) continue;
-                    mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
-                    n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
-                    n.any.family = posix.AF.INET6;
-                    n.in6.sa.flowinfo = 0;
-                    n.in6.sa.scope_id = 0;
-                }
+            for (0..rc.ns_len) |index| {
+                var n = ns_buffer[index];
+                if (n.any.family != posix.AF.INET) continue;
+                mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
+                n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
+                n.any.family = posix.AF.INET6;
+                n.in6.sa.flowinfo = 0;
+                n.in6.sa.scope_id = 0;
             }
             sl = @sizeOf(posix.sockaddr.in6);
         }
@@ -1756,10 +1755,9 @@ const ResolvConf = struct {
                 var i: usize = 0;
                 while (i < queries.len) : (i += 1) {
                     if (answers[i].len == 0) {
-                        for (&ns_arr) |*ns| {
-                            if (ns.*) |*n| {
-                                _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &n.any, sl) catch undefined;
-                            }
+                        for (0..rc.ns_len) |index| {
+                            const n = ns_buffer[index];
+                            _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &n.any, sl) catch undefined;
                         }
                     }
                 }
@@ -1780,10 +1778,9 @@ const ResolvConf = struct {
                 if (rlen < 4) continue;
 
                 // Ignore replies from addresses we didn't send to
-                const ns = for (ns_arr) |ns| {
-                    if (ns) |n| {
-                        if (n.eql(sa)) break n;
-                    }
+                const ns = for (0..rc.ns_len) |index| {
+                    const n = ns_buffer[index];
+                    if (n.eql(sa)) break n;
                 } else continue;
 
                 // Find which query this answer goes with, if any

From 8f73c15fbccee661dc982d791acc70ace2e38548 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 21:37:26 +0200
Subject: [PATCH 09/17] handle index out of bounds

---
 lib/std/net.zig | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 634eb5d177b8..ca7cc5f59705 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1683,7 +1683,8 @@ const ResolvConf = struct {
 
         var ns_buffer: [3]Address = undefined;
 
-        for (0..rc.ns_len) |index| {
+        var index: u2 = 0;
+        while (index < rc.ns_len) : (index += 1) {
             const ip = rc.ns_buffer[index];
             ns_buffer[index] = ip.addr;
             assert(ns_buffer[index].getPort() == 53);
@@ -1718,8 +1719,9 @@ const ResolvConf = struct {
                 std.os.linux.IPV6.V6ONLY,
                 &mem.toBytes(@as(c_int, 0)),
             );
-            for (0..rc.ns_len) |index| {
-                var n = ns_buffer[index];
+            var i: u2 = 0;
+            while (i < rc.ns_len) : (i += 1) {
+                var n = ns_buffer[i];
                 if (n.any.family != posix.AF.INET) continue;
                 mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
                 n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
@@ -1755,8 +1757,9 @@ const ResolvConf = struct {
                 var i: usize = 0;
                 while (i < queries.len) : (i += 1) {
                     if (answers[i].len == 0) {
-                        for (0..rc.ns_len) |index| {
-                            const n = ns_buffer[index];
+                        var idx: u2 = 0;
+                        while (idx < rc.ns_len) : (idx += 1) {
+                            const n = ns_buffer[idx];
                             _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &n.any, sl) catch undefined;
                         }
                     }
@@ -1778,8 +1781,9 @@ const ResolvConf = struct {
                 if (rlen < 4) continue;
 
                 // Ignore replies from addresses we didn't send to
-                const ns = for (0..rc.ns_len) |index| {
-                    const n = ns_buffer[index];
+                var idx: u2 = 0;
+                const ns = while (idx < rc.ns_len) : (idx += 1) {
+                    const n = ns_buffer[idx];
                     if (n.eql(sa)) break n;
                 } else continue;
 

From 85e99e832fe3d2341b09bba41f22048778c30e29 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Tue, 16 Sep 2025 21:44:53 +0200
Subject: [PATCH 10/17] named ns_buffer to ns_addr_buffer

---
 lib/std/net.zig | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index ca7cc5f59705..d435314a0ed1 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1681,13 +1681,13 @@ const ResolvConf = struct {
         var sl: posix.socklen_t = @sizeOf(posix.sockaddr.in);
         var family: posix.sa_family_t = posix.AF.INET;
 
-        var ns_buffer: [3]Address = undefined;
+        var ns_addr_buffer: [3]Address = undefined;
 
         var index: u2 = 0;
         while (index < rc.ns_len) : (index += 1) {
             const ip = rc.ns_buffer[index];
-            ns_buffer[index] = ip.addr;
-            assert(ns_buffer[index].getPort() == 53);
+            ns_addr_buffer[index] = ip.addr;
+            assert(ns_addr_buffer[index].getPort() == 53);
             if (ip.addr.any.family != posix.AF.INET) {
                 family = posix.AF.INET6;
             }
@@ -1721,7 +1721,7 @@ const ResolvConf = struct {
             );
             var i: u2 = 0;
             while (i < rc.ns_len) : (i += 1) {
-                var n = ns_buffer[i];
+                var n = ns_addr_buffer[i];
                 if (n.any.family != posix.AF.INET) continue;
                 mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
                 n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
@@ -1759,7 +1759,7 @@ const ResolvConf = struct {
                     if (answers[i].len == 0) {
                         var idx: u2 = 0;
                         while (idx < rc.ns_len) : (idx += 1) {
-                            const n = ns_buffer[idx];
+                            const n = ns_addr_buffer[idx];
                             _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &n.any, sl) catch undefined;
                         }
                     }
@@ -1782,8 +1782,8 @@ const ResolvConf = struct {
 
                 // Ignore replies from addresses we didn't send to
                 var idx: u2 = 0;
-                const ns = while (idx < rc.ns_len) : (idx += 1) {
-                    const n = ns_buffer[idx];
+                const ns_addr = while (idx < rc.ns_len) : (idx += 1) {
+                    const n = ns_addr_buffer[idx];
                     if (n.eql(sa)) break n;
                 } else continue;
 
@@ -1803,7 +1803,7 @@ const ResolvConf = struct {
                     0, 3 => {},
                     2 => if (servfail_retry != 0) {
                         servfail_retry -= 1;
-                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
+                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns_addr.any, sl) catch undefined;
                     },
                     else => continue,
                 }

From c0ff44a7af65088e493102b4d76d2ac2611242dd Mon Sep 17 00:00:00 2001
From: usebeforefree <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 10:30:13 +0000
Subject: [PATCH 11/17] Update lib/std/net.zig
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Андрей Краевский <75577902+AndrewKraevskii@users.noreply.github.com>
---
 lib/std/net.zig | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index d435314a0ed1..4ebcfc45ddf2 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1683,11 +1683,9 @@ const ResolvConf = struct {
 
         var ns_addr_buffer: [3]Address = undefined;
 
-        var index: u2 = 0;
-        while (index < rc.ns_len) : (index += 1) {
-            const ip = rc.ns_buffer[index];
-            ns_addr_buffer[index] = ip.addr;
-            assert(ns_addr_buffer[index].getPort() == 53);
+        for (rc.ns_buffer[0..rc.ns_len], ns_addr_buffer[0..rc.ns_len]) |ip, *addr|
+            addr.* = ip.addr;
+            assert(addr.getPort() == 53);
             if (ip.addr.any.family != posix.AF.INET) {
                 family = posix.AF.INET6;
             }

From d9d06adeadbe26b052096ac436ad409e8f54acbc Mon Sep 17 00:00:00 2001
From: usebeforefree <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 10:30:31 +0000
Subject: [PATCH 12/17] Update lib/std/net.zig
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Андрей Краевский <75577902+AndrewKraevskii@users.noreply.github.com>
---
 lib/std/net.zig | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 4ebcfc45ddf2..6ed1197b8590 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1717,9 +1717,7 @@ const ResolvConf = struct {
                 std.os.linux.IPV6.V6ONLY,
                 &mem.toBytes(@as(c_int, 0)),
             );
-            var i: u2 = 0;
-            while (i < rc.ns_len) : (i += 1) {
-                var n = ns_addr_buffer[i];
+            for (ns_addr_buffer[0..rc.ns_len]) |*n| {
                 if (n.any.family != posix.AF.INET) continue;
                 mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
                 n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;

From 08c887af67a772f748ff13aa72ee556414c69a95 Mon Sep 17 00:00:00 2001
From: usebeforefree <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 10:30:50 +0000
Subject: [PATCH 13/17] Update lib/std/net.zig
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Андрей Краевский <75577902+AndrewKraevskii@users.noreply.github.com>
---
 lib/std/net.zig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 6ed1197b8590..baa29825821e 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1830,7 +1830,7 @@ fn linuxLookupNameFromNumericUnspec(
     name: []const u8,
     port: u16,
 ) !void {
-    if (addrs_len.* >= addrs.len - 1) return error.OutOfMemory;
+    if (addrs_len.* == addrs.len) return error.OutOfMemory;
 
     const address = try Address.resolveIp(name, port);
     addrs[addrs_len.*] = .{ .addr = address };

From 8ace2ad67acb2ae4403da4b5c798b0d0f9ae3cfd Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 12:34:18 +0200
Subject: [PATCH 14/17] add missing bracket

---
 lib/std/net.zig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index baa29825821e..25101bc73f85 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1683,7 +1683,7 @@ const ResolvConf = struct {
 
         var ns_addr_buffer: [3]Address = undefined;
 
-        for (rc.ns_buffer[0..rc.ns_len], ns_addr_buffer[0..rc.ns_len]) |ip, *addr|
+        for (rc.ns_buffer[0..rc.ns_len], ns_addr_buffer[0..rc.ns_len]) |ip, *addr| {
             addr.* = ip.addr;
             assert(addr.getPort() == 53);
             if (ip.addr.any.family != posix.AF.INET) {

From 9828bdc92484ece97899b69ef8a651887361ec3c Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 13:57:02 +0200
Subject: [PATCH 15/17] simplified loops

---
 lib/std/net.zig | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 25101bc73f85..9c469051b57b 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1717,13 +1717,13 @@ const ResolvConf = struct {
                 std.os.linux.IPV6.V6ONLY,
                 &mem.toBytes(@as(c_int, 0)),
             );
-            for (ns_addr_buffer[0..rc.ns_len]) |*n| {
-                if (n.any.family != posix.AF.INET) continue;
-                mem.writeInt(u32, n.in6.sa.addr[12..], n.in.sa.addr, native_endian);
-                n.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
-                n.any.family = posix.AF.INET6;
-                n.in6.sa.flowinfo = 0;
-                n.in6.sa.scope_id = 0;
+            for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
+                if (ns.any.family != posix.AF.INET) continue;
+                mem.writeInt(u32, ns.in6.sa.addr[12..], ns.in.sa.addr, native_endian);
+                ns.in6.sa.addr[0..12].* = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff".*;
+                ns.any.family = posix.AF.INET6;
+                ns.in6.sa.flowinfo = 0;
+                ns.in6.sa.scope_id = 0;
             }
             sl = @sizeOf(posix.sockaddr.in6);
         }
@@ -1753,10 +1753,8 @@ const ResolvConf = struct {
                 var i: usize = 0;
                 while (i < queries.len) : (i += 1) {
                     if (answers[i].len == 0) {
-                        var idx: u2 = 0;
-                        while (idx < rc.ns_len) : (idx += 1) {
-                            const n = ns_addr_buffer[idx];
-                            _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &n.any, sl) catch undefined;
+                         for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
+                            _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
                         }
                     }
                 }
@@ -1777,10 +1775,8 @@ const ResolvConf = struct {
                 if (rlen < 4) continue;
 
                 // Ignore replies from addresses we didn't send to
-                var idx: u2 = 0;
-                const ns_addr = while (idx < rc.ns_len) : (idx += 1) {
-                    const n = ns_addr_buffer[idx];
-                    if (n.eql(sa)) break n;
+                const ns_addr = for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
+                    if (ns.eql(sa)) break ns;
                 } else continue;
 
                 // Find which query this answer goes with, if any

From fd06cfd061245d77da32e43e331d4d71f5c8fc93 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 14:04:23 +0200
Subject: [PATCH 16/17] removed pointless renames

---
 lib/std/net.zig | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 9c469051b57b..6cffb36fa3d3 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1683,10 +1683,10 @@ const ResolvConf = struct {
 
         var ns_addr_buffer: [3]Address = undefined;
 
-        for (rc.ns_buffer[0..rc.ns_len], ns_addr_buffer[0..rc.ns_len]) |ip, *addr| {
-            addr.* = ip.addr;
-            assert(addr.getPort() == 53);
-            if (ip.addr.any.family != posix.AF.INET) {
+        for (ns_addr_buffer[0..rc.ns_len], rc.ns_buffer[0..rc.ns_len]) |*ns, iplit| {
+            ns.* = iplit.addr;
+            assert(ns.getPort() == 53);
+            if (iplit.addr.any.family != posix.AF.INET) {
                 family = posix.AF.INET6;
             }
         }
@@ -1753,7 +1753,7 @@ const ResolvConf = struct {
                 var i: usize = 0;
                 while (i < queries.len) : (i += 1) {
                     if (answers[i].len == 0) {
-                         for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
+                        for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
                             _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
                         }
                     }
@@ -1775,7 +1775,7 @@ const ResolvConf = struct {
                 if (rlen < 4) continue;
 
                 // Ignore replies from addresses we didn't send to
-                const ns_addr = for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
+                const ns = for (ns_addr_buffer[0..rc.ns_len]) |*ns| {
                     if (ns.eql(sa)) break ns;
                 } else continue;
 
@@ -1795,7 +1795,7 @@ const ResolvConf = struct {
                     0, 3 => {},
                     2 => if (servfail_retry != 0) {
                         servfail_retry -= 1;
-                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns_addr.any, sl) catch undefined;
+                        _ = posix.sendto(fd, queries[i], posix.MSG.NOSIGNAL, &ns.any, sl) catch undefined;
                     },
                     else => continue,
                 }

From 20ba56b64e636e7fe6278a165545b4c1a05da237 Mon Sep 17 00:00:00 2001
From: marko <marko03kostic@protonmail.com>
Date: Wed, 17 Sep 2025 18:27:23 +0200
Subject: [PATCH 17/17] ignore entries past the third one

---
 lib/std/net.zig | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/std/net.zig b/lib/std/net.zig
index 6cffb36fa3d3..5426d768ac71 100644
--- a/lib/std/net.zig
+++ b/lib/std/net.zig
@@ -1826,7 +1826,8 @@ fn linuxLookupNameFromNumericUnspec(
     name: []const u8,
     port: u16,
 ) !void {
-    if (addrs_len.* == addrs.len) return error.OutOfMemory;
+    // Ignore new nameserver entries past the third one
+    if (addrs_len.* == addrs.len) return;
 
     const address = try Address.resolveIp(name, port);
     addrs[addrs_len.*] = .{ .addr = address };