mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 13:00:06 +00:00
9c443ac455
The inline and library functions that the CMSG_NXTHDR macro may expand to increment the pointer to the header before checking the stride of the increment against available space. Since C only allows incrementing pointers to one past the end of an array, the increment must be done after a length check. This commit fixes that and includes a regression test for CMSG_FIRSTHDR and CMSG_NXTHDR. The Linux, Hurd, and generic headers are all changed. Tested on Linux on armv7hl, i686, x86_64, aarch64, ppc64le, and s390x. [BZ #28846] Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
93 lines
3.4 KiB
C
93 lines
3.4 KiB
C
/* Test ancillary data header creation.
|
|
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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
/* We use the preprocessor to generate the function/macro tests instead of
|
|
using indirection because having all the macro expansions alongside
|
|
each other lets the compiler warn us about suspicious pointer
|
|
arithmetic across subsequent CMSG_{FIRST,NXT}HDR expansions. */
|
|
|
|
#include <stdint.h>
|
|
|
|
#define RUN_TEST_CONCAT(suffix) run_test_##suffix
|
|
#define RUN_TEST_FUNCNAME(suffix) RUN_TEST_CONCAT (suffix)
|
|
|
|
static void
|
|
RUN_TEST_FUNCNAME (CMSG_NXTHDR_IMPL) (void)
|
|
{
|
|
struct msghdr m = {0};
|
|
struct cmsghdr *cmsg;
|
|
char cmsgbuf[3 * CMSG_SPACE (sizeof (PAYLOAD))] = {0};
|
|
|
|
m.msg_control = cmsgbuf;
|
|
m.msg_controllen = sizeof (cmsgbuf);
|
|
|
|
/* First header should point to the start of the buffer. */
|
|
cmsg = CMSG_FIRSTHDR (&m);
|
|
TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf);
|
|
|
|
/* If the first header length consumes the entire buffer, there is no
|
|
space remaining for additional headers. */
|
|
cmsg->cmsg_len = sizeof (cmsgbuf);
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg == NULL);
|
|
|
|
/* The first header length is so big, using it would cause an overflow. */
|
|
cmsg = CMSG_FIRSTHDR (&m);
|
|
TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf);
|
|
cmsg->cmsg_len = SIZE_MAX;
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg == NULL);
|
|
|
|
/* The first header leaves just enough space to hold another header. */
|
|
cmsg = CMSG_FIRSTHDR (&m);
|
|
TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf);
|
|
cmsg->cmsg_len = sizeof (cmsgbuf) - sizeof (struct cmsghdr);
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg != NULL);
|
|
|
|
/* The first header leaves space but not enough for another header. */
|
|
cmsg = CMSG_FIRSTHDR (&m);
|
|
TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf);
|
|
cmsg->cmsg_len ++;
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg == NULL);
|
|
|
|
/* The second header leaves just enough space to hold another header. */
|
|
cmsg = CMSG_FIRSTHDR (&m);
|
|
TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf);
|
|
cmsg->cmsg_len = CMSG_LEN (sizeof (PAYLOAD));
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg != NULL);
|
|
cmsg->cmsg_len = sizeof (cmsgbuf)
|
|
- CMSG_SPACE (sizeof (PAYLOAD)) /* First header. */
|
|
- sizeof (struct cmsghdr);
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg != NULL);
|
|
|
|
/* The second header leaves space but not enough for another header. */
|
|
cmsg = CMSG_FIRSTHDR (&m);
|
|
TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf);
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg != NULL);
|
|
cmsg->cmsg_len ++;
|
|
cmsg = CMSG_NXTHDR_IMPL (&m, cmsg);
|
|
TEST_VERIFY_EXIT (cmsg == NULL);
|
|
|
|
return;
|
|
}
|