strace/tests/poll.c
Dmitry V. Levin d54388e1ce print_array: enhance printing of unfetchable object addresses
When umoven_func invocation fails to fetch data, it prints the faulty
address.  If this happens to a subsequent umoven_func invocation,
the printed address may be undistinguishable from a valid data printed
by print_func, e.g. when the data is printed in a numeric form like
[0x1, 0x2, 0x3, 0xdefaced].

Fix this source of confusion by moving the printing of the faulty
address from umoven_func to print_array itself.  This change renames
umoven_func to tfetch_mem_func and changes its semantics, so that
 - tfetch_mem_func never prints anything;
 - tfetch_mem_func returns true if the fetch succeeded,
   and false otherwise.

* defs.h (print_array): Replace umoven_func argument with
tfetch_mem_func.
* util.c (print_array): Replace umoven_func argument with
tfetch_mem_func, document expected tfetch_mem_func return value
semantics.  When tfetch_mem_func returns false, print either addr
or "... /* addr */" depending on the context (inside the array or not).
* bpf.c (print_ebpf_prog, print_bpf_prog_info,
BEGIN_BPF_CMD_DECODER(BPF_PROG_QUERY)): Replace umoven_or_printaddr
argument of print_array with tfetch_mem.
* bpf_filter.c (print_bpf_fprog): Likewise.
* btrfs.c (btrfs_print_logical_ino_container,
btrfs_print_ino_path_container, btrfs_print_qgroup_inherit,
btrfs_ioctl): Likewise.
* dm.c (dm_decode_dm_target_deps): Likewise.
* epoll.c (epoll_wait_common): Likewise.
* file_ioctl.c (file_ioctl): Likewise.
* ipc_sem.c (tprint_sembuf_array): Likewise.
* kexec.c (print_kexec_segments): Likewise.
* mem.c (SYS_FUNC(subpage_prot)): Likewise.
* net.c (print_getsockopt): Likewise.
* netlink.c (decode_nlmsgerr_attr_cookie): Likewise.
* netlink_netlink_diag.c (decode_netlink_diag_groups): Likewise.
* netlink_packet_diag.c (decode_packet_diag_mclist): Likewise.
* netlink_unix_diag.c (decode_unix_diag_inode): Likewise.
* nlattr.c (decode_nla_meminfo): Likewise.
* numa.c (print_nodemask, SYS_FUNC(move_pages),
* perf_ioctl.c (perf_ioctl_query_bpf): Likewise.
* poll.c (decode_poll_entering): Likewise.
* printsiginfo.c (print_siginfo_array): Likewise.
* rtnl_tc.c (decode_tca_stab_data): Likewise.
* sock.c (decode_ifconf): Likewise.
* uid.c (print_groups): Likewise.
* io.c (SYS_FUNC(io_submit), SYS_FUNC(io_getevents)): Replace
umoven_or_printaddr argument of print_array with tfetch_mem.
(tprint_iov_upto): Replace umoven_or_printaddr_ignore_syserror
with tfetch_mem_ignore_syserror.
* v4l2.c (print_v4l2_format_fmt): Replace umoven_or_printaddr argument
of print_array with tfetch_mem.
(print_v4l2_ext_controls): Replace umoven_or_printaddr_ignore_syserror
with tfetch_mem_ignore_syserror.
* mmsghdr.c (fetch_struct_mmsghdr_or_printaddr): Rename
to fetch_struct_mmsghdr_for_print, do not print address, return bool.
(decode_mmsgvec): Replace fetch_struct_mmsghdr_or_printaddr
with fetch_struct_mmsghdr_for_print.
* tests/aio.c (main): Update expected output.
* tests/bpf.c (print_BPF_PROG_QUERY_attr5): Likewise.
* tests/ioctl_perf-success.c (main): Likewise.
* tests/ioctl_v4l2.c (main): Update expected output.
* tests/kexec_load.c (main): Likewise.
* tests/mmsg_name.c (test_mmsg_name): Update expected output.
* tests/move_pages.c (print_page_array, print_node_array): Likewise.
* tests/poll.c (print_pollfd_array_entering): Likewise.
* tests/preadv-pwritev.c (main): Likewise.
* tests/preadv2-pwritev2.c (dumpio): Likewise.
* tests/process_vm_readv_writev.c (print_iov): Likewise.
* tests/pwritev.c (print_iovec): Likewise.
* tests/readv.c (main): Likewise.
* tests/seccomp-filter-v.c
* tests/semop.c (main): Likewise.
* tests/set_mempolicy.c (print_nodes): Likewise.
* tests/setgroups.c (main): Likewise.
* tests/test_nlattr.h (print_nlattr) Likewise.

Co-Authored-by: Eugene Syromyatnikov <evgsyr@gmail.com>
2018-05-29 09:58:10 +00:00

315 lines
8.4 KiB
C

/*
* Check decoding of poll syscall.
*
* Copyright (c) 2016-2018 Dmitry V. Levin <ldv@altlinux.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "tests.h"
#include <asm/unistd.h>
#ifdef __NR_poll
# include <assert.h>
# include <errno.h>
# include <poll.h>
# include <stdio.h>
# include <stdlib.h>
# include <string.h>
# include <unistd.h>
#define PRINT_EVENT(flag, member) \
do { \
if (member & flag) { \
if (member != pfd->member) \
tprintf("|"); \
tprintf(#flag); \
member &= ~flag; \
} \
} while (0)
static void
print_pollfd_entering(const struct pollfd *const pfd)
{
tprintf("{fd=%d", pfd->fd);
if (pfd->fd >= 0) {
tprintf(", events=");
short events = pfd->events;
if (pfd->events) {
PRINT_EVENT(POLLIN, events);
PRINT_EVENT(POLLPRI, events);
PRINT_EVENT(POLLOUT, events);
#ifdef POLLRDNORM
PRINT_EVENT(POLLRDNORM, events);
#endif
#ifdef POLLWRNORM
PRINT_EVENT(POLLWRNORM, events);
#endif
#ifdef POLLRDBAND
PRINT_EVENT(POLLRDBAND, events);
#endif
#ifdef POLLWRBAND
PRINT_EVENT(POLLWRBAND, events);
#endif
PRINT_EVENT(POLLERR, events);
PRINT_EVENT(POLLHUP, events);
PRINT_EVENT(POLLNVAL, events);
} else
tprintf("0");
}
tprintf("}");
}
static void
print_pollfd_array_entering(const struct pollfd *const pfd,
const unsigned int size,
const unsigned int valid,
const unsigned int abbrev)
{
tprintf("[");
unsigned int i;
for (i = 0; i < size; ++i) {
if (i)
tprintf(", ");
if (i >= valid) {
tprintf("... /* %p */", &pfd[i]);
break;
}
if (i >= abbrev) {
tprintf("...");
break;
}
print_pollfd_entering(&pfd[i]);
}
tprintf("]");
}
static void
print_pollfd_exiting(const struct pollfd *const pfd,
unsigned int *const seen,
const unsigned int abbrev)
{
if (!pfd->revents || pfd->fd < 0 || *seen > abbrev)
return;
if (*seen)
tprintf(", ");
++(*seen);
if (*seen > abbrev) {
tprintf("...");
return;
}
tprintf("{fd=%d, revents=", pfd->fd);
short revents = pfd->revents;
PRINT_EVENT(POLLIN, revents);
PRINT_EVENT(POLLPRI, revents);
PRINT_EVENT(POLLOUT, revents);
#ifdef POLLRDNORM
PRINT_EVENT(POLLRDNORM, revents);
#endif
#ifdef POLLWRNORM
PRINT_EVENT(POLLWRNORM, revents);
#endif
#ifdef POLLRDBAND
PRINT_EVENT(POLLRDBAND, revents);
#endif
#ifdef POLLWRBAND
PRINT_EVENT(POLLWRBAND, revents);
#endif
PRINT_EVENT(POLLERR, revents);
PRINT_EVENT(POLLHUP, revents);
PRINT_EVENT(POLLNVAL, revents);
tprintf("}");
}
static void
print_pollfd_array_exiting(const struct pollfd *const pfd,
const unsigned int size,
const unsigned int abbrev)
{
tprintf("[");
unsigned int seen = 0;
unsigned int i;
for (i = 0; i < size; ++i)
print_pollfd_exiting(&pfd[i], &seen, abbrev);
tprintf("]");
}
int
main(int ac, char **av)
{
# ifdef PATH_TRACING_FD
skip_if_unavailable("/proc/self/fd/");
# endif
tprintf("%s", "");
assert(syscall(__NR_poll, NULL, 42, 0) == -1);
if (ENOSYS == errno)
perror_msg_and_skip("poll");
# ifndef PATH_TRACING_FD
tprintf("poll(NULL, 42, 0) = -1 EFAULT (%m)\n");
# endif
int fds[2];
if (pipe(fds) || pipe(fds))
perror_msg_and_fail("pipe");
const unsigned int abbrev = (ac > 1) ? atoi(av[1]) : -1;
const struct pollfd pfds0[] = {
{ .fd = 0, .events = POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND },
{ .fd = 1, .events = POLLOUT | POLLWRNORM | POLLWRBAND },
{ .fd = fds[0], .events = POLLIN | POLLPRI },
{ .fd = fds[1], .events = POLLOUT },
{ .fd = 2, .events = POLLOUT | POLLWRBAND }
};
struct pollfd *const tail_fds0 = tail_memdup(pfds0, sizeof(pfds0));
const int timeout = 42;
int rc = syscall(__NR_poll, tail_fds0, 0, timeout);
assert(rc == 0);
# ifndef PATH_TRACING_FD
tprintf("poll([], 0, %d) = %d (Timeout)\n", timeout, rc);
# endif
rc = syscall(__NR_poll, tail_fds0, ARRAY_SIZE(pfds0), timeout);
assert(rc == 3);
# ifndef PATH_TRACING_FD
tprintf("poll(");
print_pollfd_array_entering(tail_fds0, ARRAY_SIZE(pfds0),
ARRAY_SIZE(pfds0), abbrev);
tprintf(", %u, %d) = %d (",
(unsigned int) ARRAY_SIZE(pfds0), timeout, rc);
print_pollfd_array_exiting(tail_fds0, ARRAY_SIZE(pfds0), abbrev);
tprintf(")\n");
# endif /* !PATH_TRACING_FD */
tail_fds0[0].fd = -1;
tail_fds0[2].fd = -3;
tail_fds0[4].events = 0;
rc = syscall(__NR_poll, tail_fds0, ARRAY_SIZE(pfds0), timeout);
assert(rc == 2);
# ifndef PATH_TRACING_FD
tprintf("poll(");
print_pollfd_array_entering(tail_fds0, ARRAY_SIZE(pfds0),
ARRAY_SIZE(pfds0), abbrev);
tprintf(", %u, %d) = %d (",
(unsigned int) ARRAY_SIZE(pfds0), timeout, rc);
print_pollfd_array_exiting(tail_fds0, ARRAY_SIZE(pfds0), abbrev);
tprintf(")\n");
# endif /* !PATH_TRACING_FD */
tail_fds0[1].fd = -2;
tail_fds0[4].fd = -5;
rc = syscall(__NR_poll, tail_fds0, ARRAY_SIZE(pfds0), timeout);
assert(rc == 1);
# ifndef PATH_TRACING_FD
tprintf("poll(");
print_pollfd_array_entering(tail_fds0, ARRAY_SIZE(pfds0),
ARRAY_SIZE(pfds0), abbrev);
tprintf(", %u, %d) = %d (",
(unsigned int) ARRAY_SIZE(pfds0), timeout, rc);
print_pollfd_array_exiting(tail_fds0, ARRAY_SIZE(pfds0), abbrev);
tprintf(")\n");
# endif /* !PATH_TRACING_FD */
struct pollfd pfds1[] = {
{ .fd = 1, .events = POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND },
{ .fd = 0, .events = POLLOUT | POLLWRNORM | POLLWRBAND }
};
struct pollfd *const tail_fds1 = tail_memdup(pfds1, sizeof(pfds1));
rc = syscall(__NR_poll, tail_fds1, ARRAY_SIZE(pfds1), timeout);
assert(rc == 0);
# ifndef PATH_TRACING_FD
tprintf("poll(");
print_pollfd_array_entering(tail_fds1, ARRAY_SIZE(pfds1),
ARRAY_SIZE(pfds1), abbrev);
tprintf(", %u, %d) = %d (Timeout)\n",
(unsigned int) ARRAY_SIZE(pfds1), timeout, rc);
# endif /* !PATH_TRACING_FD */
const void *const efault = tail_fds0 + ARRAY_SIZE(pfds0);
rc = syscall(__NR_poll, efault, 1, 0);
assert(rc == -1);
# ifndef PATH_TRACING_FD
tprintf("poll(%p, 1, 0) = -1 EFAULT (%m)\n", efault);
# endif
const unsigned int valid = 1;
const void *const epfds = tail_fds0 + ARRAY_SIZE(pfds0) - valid;
rc = syscall(__NR_poll, epfds, valid + 1, 0);
assert(rc == -1);
# ifndef PATH_TRACING_FD
tprintf("poll(");
print_pollfd_array_entering(epfds, valid + 1, valid, abbrev);
errno = EFAULT;
tprintf(", %u, 0) = -1 EFAULT (%m)\n", valid + 1);
# endif /* !PATH_TRACING_FD */
# ifdef PATH_TRACING_FD
memcpy(tail_fds0, pfds0, sizeof(pfds0));
tail_fds0[4].fd = PATH_TRACING_FD;
rc = syscall(__NR_poll, tail_fds0, ARRAY_SIZE(pfds0), timeout);
assert(rc == 3);
tprintf("poll(");
print_pollfd_array_entering(tail_fds0, ARRAY_SIZE(pfds0),
ARRAY_SIZE(pfds0), abbrev);
tprintf(", %u, %d) = %d (",
(unsigned int) ARRAY_SIZE(pfds0), timeout, rc);
print_pollfd_array_exiting(tail_fds0, ARRAY_SIZE(pfds0), abbrev);
tprintf(")\n");
rc = syscall(__NR_poll, epfds, valid + 1, 0);
assert(rc == -1);
/* the 1st pollfd element is readable and contains PATH_TRACING_FD */
tprintf("poll(");
print_pollfd_array_entering(epfds, valid + 1, valid, abbrev);
errno = EFAULT;
tprintf(", %u, 0) = -1 EFAULT (%m)\n", valid + 1);
# endif /* PATH_TRACING_FD */
tprintf("+++ exited with 0 +++\n");
return 0;
}
#else
SKIP_MAIN_UNDEFINED("__NR_poll")
#endif