From 46ee9243f23f56ded21bf8507f86a55980b04ed1 Mon Sep 17 00:00:00 2001 From: Siddhesh Poyarekar Date: Fri, 25 Oct 2013 10:22:12 +0530 Subject: Fix stack overflow due to large AF_INET6 requests Resolves #16072 (CVE-2013-4458). This patch fixes another stack overflow in getaddrinfo when it is called with AF_INET6. The AF_UNSPEC case was fixed as CVE-2013-1914, but the AF_INET6 case went undetected back then. (cherry picked from commit 6f95434fd488e9b72117f9b93ec2e2dbf397a4d3) --- sysdeps/posix/getaddrinfo.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c index 7bb3ded9af..2e97255133 100644 --- a/sysdeps/posix/getaddrinfo.c +++ b/sysdeps/posix/getaddrinfo.c @@ -197,7 +197,22 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp, &rc, &herrno, NULL, &localcanon)); \ if (rc != ERANGE || herrno != NETDB_INTERNAL) \ break; \ - tmpbuf = extend_alloca (tmpbuf, tmpbuflen, 2 * tmpbuflen); \ + if (!malloc_tmpbuf && __libc_use_alloca (alloca_used + 2 * tmpbuflen)) \ + tmpbuf = extend_alloca_account (tmpbuf, tmpbuflen, 2 * tmpbuflen, \ + alloca_used); \ + else \ + { \ + char *newp = realloc (malloc_tmpbuf ? tmpbuf : NULL, \ + 2 * tmpbuflen); \ + if (newp == NULL) \ + { \ + result = -EAI_MEMORY; \ + goto free_and_return; \ + } \ + tmpbuf = newp; \ + malloc_tmpbuf = true; \ + tmpbuflen = 2 * tmpbuflen; \ + } \ } \ if (status == NSS_STATUS_SUCCESS && rc == 0) \ h = &th; \ @@ -209,7 +224,8 @@ gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp, { \ __set_h_errno (herrno); \ _res.options |= old_res_options & RES_USE_INET6; \ - return -EAI_SYSTEM; \ + result = -EAI_SYSTEM; \ + goto free_and_return; \ } \ if (herrno == TRY_AGAIN) \ no_data = EAI_AGAIN; \ -- cgit 1.4.1