@@ -321,6 +321,7 @@ tests := \
tst-getaddrinfo \
tst-getaddrinfo2 \
tst-getaddrinfo3 \
+ tst-getaddrinfo6 \
tst-gethnm \
tst-getpw \
tst-gshadow \
@@ -95,7 +95,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
struct gaih_service
{
const char *name;
- int num;
+ unsigned long num;
};
struct gaih_servtuple
@@ -2375,7 +2375,19 @@ getaddrinfo (const char *name, const char *service,
return EAI_NONAME;
}
- gaih_service.num = -1;
+ /* 0 means "no numeric port provided" (which is equivalent to
+ passing 0 as port) */
+ gaih_service.num = 0;
+ }
+ /* port number must be in range [0, USHRT_MAX].
+ Any other value is invalid.
+ strtoul returns ULONG_MAX in case of out-of-range
+ input and it is caught by this check */
+ else if (gaih_service.num > USHRT_MAX)
+ {
+ /* the provided port number is invalid */
+ __free_in6ai (in6ai);
+ return EAI_NONAME;
}
pservice = &gaih_service;
new file mode 100644
@@ -0,0 +1,84 @@
+/* Test invalid port/service lookup [BZ #16208].
+ Copyright (C) 2014-2024 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+
+static int
+do_one_test (const char *service, int expected_err)
+{
+ const int family[2] = { AF_INET, AF_INET6 };
+ struct addrinfo hints, *aitop;
+ int index, gaierr;
+ int result = 0;
+
+ for (index = 0; index < sizeof (family) / sizeof (family[0]); ++index)
+ {
+ memset (&hints, '\0', sizeof (hints));
+ hints.ai_family = family[index];
+
+ gaierr = getaddrinfo (NULL, service, &hints, &aitop);
+ if (gaierr != expected_err)
+ {
+ printf ("FAIL getaddrinfo returned %d, should return %d\n",
+ gaierr, expected_err);
+ result = 1;
+ }
+ }
+
+ return result;
+}
+
+
+static int
+do_test (void)
+{
+ int err = 0;
+
+ // 0 is accepted, test should succeed
+ err |= do_one_test ("0", 0);
+ err |= do_one_test ("70000", EAI_NONAME);
+ err |= do_one_test ("-1", EAI_NONAME);
+
+ // INT_MIN
+ err |= do_one_test ("-2147483648", EAI_NONAME);
+ // INT_MAX
+ err |= do_one_test ("2147483647", EAI_NONAME);
+ // UINT_MAX / ULONG_MAX 32bit
+ err |= do_one_test ("4294967295", EAI_NONAME);
+ // ULONG_MAX 64bit / ULLONG_MAX
+ err |= do_one_test ("18446744073709551615", EAI_NONAME);
+ // LONG_MAX 64bit / LLONG_MAX
+ err |= do_one_test ("9223372036854775807", EAI_NONAME);
+ // LONG_MIN 64bit / LLONG_MIN
+ err |= do_one_test ("-9223372036854775808", EAI_NONAME);
+
+ // ULONG_MAX 64bit +1 / ULLONG_MAX +1
+ err |= do_one_test ("18446744073709551616", EAI_NONAME);
+ // LONG_MIN 64bit -1 / LLONG_MIN -1
+ err |= do_one_test ("-9223372036854775809", EAI_NONAME);
+
+ return err;
+}
+#define TEST_FUNCTION do_test ()
+
+#include "../test-skeleton.c"
When passing a numeric string as port/service to getaddrinfo() representing a number larger than 65535, the function will not complain and will simply extract the lowest 16bits of the converted number. Specifically, the string is converted to int by calling strtoul() and later it is moved to gaih_servtuple.num after passing through htons(). For example, invoking getaddrinfo() with service equal to "70000" will result in no error and ai_addr->sin_port set to 4464. This issue was (re)discovered by researcher Anqi Chen while stress testing OpenVPN with invalid config parameters. Thanks a lot to Arne Schwabe for finding out that the root cause was hidden inside glibc. Similarly when passing an out of range value, no error is thrown while it should. Add proper checks to reject invalid values immediately. The 'num' member has been converted to unsigned long in order to properly store the result of strtoul(). Then, while checking for 'num' being greater than USHRT_MAX, we also catch overflows/out-of-range values (strtoul() returns ULONG_MAX in that case). Cc: Arne Schwabe <arne@rfc2549.org> Cc: Cristina Nita-Rotaru <crisn@ccs.neu.edu> Reported-by: Anqi Chen <chen.anqi3@northeastern.edu> Signed-off-by: Antonio Quartulli <a@unstable.cc> --- Changes from v3: * extended unit test with more notorius integer constants * rephrased comment * removed mention of 0 being invalid from commit message Changes from v2: * allowed specifying 0 as port number (equivalent to not passing any port) * changed unit-test to check success when passing 0 as port --- nss/Makefile | 1 + nss/getaddrinfo.c | 16 +++++++- nss/tst-getaddrinfo6.c | 84 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 99 insertions(+), 2 deletions(-) create mode 100644 nss/tst-getaddrinfo6.c