c-ares: Patch CVE-2022-4904

Fix ported from c-ares 1.19.0.

pkgs/development/libraries/c-ares/CVE-2022-4904.patch

@@ -0,0 +1,60 @@
+From ac596026e77244481fd68736ae7f15855803a08a Mon Sep 17 00:00:00 2001
+From: hopper-vul <hopper.vul@gmail.com>
+Date: Tue, 13 Dec 2022 19:54:21 +0800
+Subject: [PATCH] Add str len check in config_sortlist to avoid stack overflow
+
+In ares_set_sortlist, it calls config_sortlist(..., sortstr) to parse
+the input str and initialize a sortlist configuration.
+
+However, ares_set_sortlist has not any checks about the validity of the input str.
+It is very easy to create an arbitrary length stack overflow with the unchecked
+`memcpy(ipbuf, str, q-str);` and `memcpy(ipbufpfx, str, q-str);`
+statements in the config_sortlist call, which could potentially cause severe
+security impact in practical programs.
+
+This commit add necessary check for `ipbuf` and `ipbufpfx` which avoid the
+potential stack overflows.
+
+fixes #496
+
+Signed-off-by: hopper-vul <hopper.vul@gmail.com>
+---
+ src/lib/ares_init.c    | 4 ++++
+ test/ares-test-init.cc | 2 ++
+ 2 files changed, 6 insertions(+)
+
+diff --git a/src/lib/ares_init.c b/src/lib/ares_init.c
+index 7f92ef67..cc2885ee 100644
+--- a/src/lib/ares_init.c
++++ b/src/lib/ares_init.c
+@@ -1913,6 +1913,8 @@ static int config_sortlist(struct apattern **sortlist, int *nsort,
+       q = str;
+       while (*q && *q != '/' && *q != ';' && !ISSPACE(*q))
+         q++;
++      if (q-str >= 16)
++        return ARES_EBADSTR;
+       memcpy(ipbuf, str, q-str);
+       ipbuf[q-str] = '\0';
+       /* Find the prefix */
+@@ -1921,6 +1923,8 @@ static int config_sortlist(struct apattern **sortlist, int *nsort,
+           const char *str2 = q+1;
+           while (*q && *q != ';' && !ISSPACE(*q))
+             q++;
++          if (q-str >= 32)
++            return ARES_EBADSTR;
+           memcpy(ipbufpfx, str, q-str);
+           ipbufpfx[q-str] = '\0';
+           str = str2;
+diff --git a/test/ares-test-init.cc b/test/ares-test-init.cc
+index 63c6a228..ee845181 100644
+--- a/test/ares-test-init.cc
++++ b/test/ares-test-init.cc
+@@ -275,6 +275,8 @@ TEST_F(DefaultChannelTest, SetAddresses) {
+ 
+ TEST_F(DefaultChannelTest, SetSortlistFailures) {
+   EXPECT_EQ(ARES_ENODATA, ares_set_sortlist(nullptr, "1.2.3.4"));
++  EXPECT_EQ(ARES_EBADSTR, ares_set_sortlist(channel_, "111.111.111.111*/16"));
++  EXPECT_EQ(ARES_EBADSTR, ares_set_sortlist(channel_, "111.111.111.111/255.255.255.240*"));
+   EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "xyzzy ; lwk"));
+   EXPECT_EQ(ARES_SUCCESS, ares_set_sortlist(channel_, "xyzzy ; 0x123"));
+ }

pkgs/development/libraries/c-ares/default.nix

@@ -29,6 +29,7 @@ stdenv.mkDerivation rec {
       url = "https://github.com/jonringer/c-ares/commit/9806a8a2f999a8a3efa3c893f2854dce6919d5bb.patch";
       sha256 = "sha256-nh/ZKdan2/FTrouApRQA7O8KGZrLEUuWhxGOktiiGwU=";
     })
+    ./CVE-2022-4904.patch
   ];
 
   nativeBuildInputs = lib.optionals withCMake [ cmake ];