blob: 00fb3266c6be995697103afbc422ecdeec6b6173 [file] [log] [blame]
From f545ad4928fa1f27a3075265182b38a4f939a5f7 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Mon, 17 Jan 2022 10:21:34 +0100
Subject: [PATCH] CVE-2022-23218: Buffer overflow in sunrpc svcunix_create (bug
28768)
The sunrpc function svcunix_create suffers from a stack-based buffer
overflow with overlong pathname arguments.
Upstream-Status: Backport [https://sourceware.org/git/?p=glibc.git;a=commit;h=f545ad4928fa1f27a3075265182b38a4f939a5f7]
CVE: CVE-2022-23218
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Signed-off-by: Pgowda <pgowda.cve@gmail.com>
---
NEWS | 3 +++
sunrpc/Makefile | 2 +-
sunrpc/svc_unix.c | 11 ++++-------
sunrpc/tst-bug28768.c | 42 ++++++++++++++++++++++++++++++++++++++++++
4 files changed, 50 insertions(+), 8 deletions(-)
create mode 100644 sunrpc/tst-bug28768.c
diff --git a/NEWS b/NEWS
index 38a9ddb2cf..38802f0673 100644
--- a/NEWS
+++ b/NEWS
@@ -203,6 +203,9 @@ Security related changes:
parameter number when processing the expansion resulting in a crash.
Reported by Philippe Antoine.
+ CVE-2022-23218: Passing an overlong file name to the svcunix_create
+ legacy function could result in a stack-based buffer overflow.
+
The following bugs are resolved with this release:
[4737] libc: fork is not async-signal-safe
diff --git a/sunrpc/Makefile b/sunrpc/Makefile
index 183ef3dc55..a79a7195fc 100644
--- a/sunrpc/Makefile
+++ b/sunrpc/Makefile
@@ -65,7 +65,7 @@ shared-only-routines = $(routines)
endif
tests = tst-xdrmem tst-xdrmem2 test-rpcent tst-udp-error tst-udp-timeout \
- tst-udp-nonblocking
+ tst-udp-nonblocking tst-bug28768
xtests := tst-getmyaddr
ifeq ($(have-thread-library),yes)
diff --git a/sunrpc/svc_unix.c b/sunrpc/svc_unix.c
index f2280b4c49..67177a2e78 100644
--- a/sunrpc/svc_unix.c
+++ b/sunrpc/svc_unix.c
@@ -154,7 +154,10 @@ svcunix_create (int sock, u_int sendsize
SVCXPRT *xprt;
struct unix_rendezvous *r;
struct sockaddr_un addr;
- socklen_t len = sizeof (struct sockaddr_in);
+ socklen_t len = sizeof (addr);
+
+ if (__sockaddr_un_set (&addr, path) < 0)
+ return NULL;
if (sock == RPC_ANYSOCK)
{
@@ -165,12 +168,6 @@ svcunix_create (int sock, u_int sendsize
}
madesock = TRUE;
}
- memset (&addr, '\0', sizeof (addr));
- addr.sun_family = AF_UNIX;
- len = strlen (path) + 1;
- memcpy (addr.sun_path, path, len);
- len += sizeof (addr.sun_family);
-
__bind (sock, (struct sockaddr *) &addr, len);
if (__getsockname (sock, (struct sockaddr *) &addr, &len) != 0
diff --git a/sunrpc/tst-bug28768.c b/sunrpc/tst-bug28768.c
new file mode 100644
index 0000000000..35a4b7b0b3
--- /dev/null
+++ b/sunrpc/tst-bug28768.c
@@ -0,0 +1,42 @@
+/* Test to verify that long path is rejected by svcunix_create (bug 28768).
+ Copyright (C) 2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <rpc/svc.h>
+#include <shlib-compat.h>
+#include <string.h>
+#include <support/check.h>
+
+/* svcunix_create does not have a default version in linkobj/libc.so. */
+compat_symbol_reference (libc, svcunix_create, svcunix_create, GLIBC_2_1);
+
+static int
+do_test (void)
+{
+ char pathname[109];
+ memset (pathname, 'x', sizeof (pathname));
+ pathname[sizeof (pathname) - 1] = '\0';
+
+ errno = 0;
+ TEST_VERIFY (svcunix_create (RPC_ANYSOCK, 4096, 4096, pathname) == NULL);
+ TEST_COMPARE (errno, EINVAL);
+
+ return 0;
+}
+
+#include <support/test-driver.c>