/*
* Check decoding of process_vm_readv/process_vm_writev syscall.
*
* Copyright (c) 2016 Eugene Syromyatnikov <evgsyr@gmail.com>
* 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 <inttypes.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/uio.h>
#if OP_WR
# define in_iovec rmt_iovec
# define out_iovec lcl_iovec
# define in_iov rmt_iov
# define out_iov lcl_iov
#else
# define in_iovec lcl_iovec
# define out_iovec rmt_iovec
# define in_iov lcl_iov
# define out_iov rmt_iov
#endif
typedef void (*iov_print_fn)(const struct iovec *, const void *, long);
enum { MAX_SEGM_COUNT = 2, MAX_STR_LEN = 5 };
struct print_iov_arg {
uint32_t count;
uint32_t valid :1,
string :1,
addr_term:1,
check_rc :1;
uint32_t str_segms;
uint8_t str_base[MAX_SEGM_COUNT];
uint8_t str_size[MAX_SEGM_COUNT];
};
static void
print_iov(const struct iovec *iov, const void *arg_ptr, long rc)
{
const struct print_iov_arg *arg = arg_ptr;
uint32_t i;
uint32_t num_segm = 0;
uint64_t segm_offs = 0;
if (!arg || !arg->valid) {
if (iov)
printf("%p", iov);
else
printf("NULL");
return;
}
printf("[");
for (i = 0; i < arg->count; i++) {
if (i)
printf(", ");
if (i >= MAX_STR_LEN) {
printf("...");
break;
}
printf("{iov_base=");
if (arg->string && (!arg->check_rc || (rc != -1))) {
uint64_t str_left = iov[i].iov_len;
uint64_t pr_count = 0;
printf("\"");
while (str_left--) {
static const char oct_str[] = "01234567";
uint8_t c = arg->str_base[num_segm] + segm_offs;
if ((num_segm >= arg->str_segms) ||
(num_segm >= MAX_SEGM_COUNT))
error_msg_and_fail("print_iov: segment "
"count overrun");
if (pr_count++ < MAX_STR_LEN)
printf("\\%.1s%.1s%d",
(c >> 6) ?
oct_str + (c >> 6) : "",
(c >> 3) ?
oct_str + ((c >> 3) & 7) : "",
c & 7);
segm_offs++;
if (segm_offs >= arg->str_size[num_segm]) {
num_segm++;
segm_offs = 0;
}
}
printf("\"");
if (pr_count > MAX_STR_LEN)
printf("...");
} else {
if (iov[i].iov_base)
printf("%p", iov[i].iov_base);
else
printf("NULL");
}
printf(", iov_len=%zu}", iov[i].iov_len);
}
if (arg->addr_term)
printf(", %p", iov + arg->count);
printf("]");
}
static void
do_call(kernel_ulong_t pid,
kernel_ulong_t local_iov, const char *local_arg,
kernel_ulong_t liovcnt,
kernel_ulong_t remote_iov, const char *remote_arg,
kernel_ulong_t riovcnt,
kernel_ulong_t flags, iov_print_fn pr_iov)
{
long rc;
const char *errstr;
rc = syscall(OP_NR, pid, local_iov, liovcnt, remote_iov, riovcnt,
flags);
errstr = sprintrc(rc);
printf("%s(%d, ", OP_STR, (int) pid);
if (pr_iov)
pr_iov((const struct iovec *) (uintptr_t) local_iov, local_arg,
rc);
else
printf("%s", local_arg);
printf(", %lu, ", (unsigned long) liovcnt);
if (pr_iov)
pr_iov((const struct iovec *) (uintptr_t) remote_iov,
remote_arg, rc);
else
printf("%s", remote_arg);
printf(", %lu, %lu) = %s\n", (unsigned long) riovcnt,
(unsigned long) flags, errstr);
}
kernel_ulong_t
ptr_cast(void *ptr)
{
return (kernel_ulong_t) (uintptr_t) ptr;
}
int
main(void)
{
enum {
SIZE_11 = 2,
SIZE_12 = 3,
SIZE_13 = 4,
SIZE_1 = SIZE_11 + SIZE_12 + SIZE_13,
SIZE_21 = 5,
SIZE_22 = 6,
SIZE_23 = 7,
SIZE_2 = SIZE_21 + SIZE_22 + SIZE_23,
};
enum {
SEGM1_BASE = 0x80,
SEGM2_BASE = 0xA0,
};
static const kernel_ulong_t bogus_pid =
(kernel_ulong_t) 0xbadfaceddeadca57ULL;
static const kernel_ulong_t bogus_iovcnt1 =
(kernel_ulong_t) 0xdec0ded1defaced2ULL;
static const kernel_ulong_t bogus_iovcnt2 =
(kernel_ulong_t) 0xdec0ded3defaced4ULL;
static const kernel_ulong_t bogus_flags =
(kernel_ulong_t) 0xdeadc0deda7adeadULL;
pid_t my_pid = getpid();
char *data1_out = tail_alloc(SIZE_1);
char *data2_out = tail_alloc(SIZE_2);
char *data1_in = tail_alloc(SIZE_2);
char *data2_in = tail_alloc(SIZE_1);
struct iovec bogus_iovec[] = {
{ data1_out + SIZE_1, (size_t) 0xdeadfaceca57beefULL },
{ data1_in + SIZE_2, (size_t) 0xbadc0dedda7adeadULL },
{ data2_out + SIZE_2, (size_t) 0xf157facedec0ded1ULL },
{ data2_in + SIZE_1, (size_t) 0xdefaced2bea7be57ULL },
};
struct iovec out_iovec[] = {
{ data1_out, SIZE_11 },
{ data1_out + SIZE_11, SIZE_12 },
{ data1_out + SIZE_11 + SIZE_12, SIZE_13 },
{ data2_out, SIZE_21 },
{ data2_out + SIZE_21, SIZE_22 },
{ data2_out + SIZE_21 + SIZE_22, SIZE_23 },
};
struct iovec in_iovec[] = {
{ data1_in, SIZE_23 },
{ data1_in + SIZE_23, SIZE_22 },
{ data1_in + SIZE_23 + SIZE_22, SIZE_21 },
{ data2_in, SIZE_13 },
{ data2_in + SIZE_13, SIZE_12 },
{ data2_in + SIZE_13 + SIZE_12, SIZE_11 },
};
struct iovec *bogus_iov = tail_memdup(bogus_iovec, sizeof(bogus_iovec));
struct iovec *lcl_iov = tail_memdup(lcl_iovec, sizeof(lcl_iovec));
struct iovec *rmt_iov = tail_memdup(rmt_iovec, sizeof(rmt_iovec));
struct print_iov_arg bogus_arg = { ARRAY_SIZE(bogus_iovec), 1 };
struct print_iov_arg lcl_arg = { ARRAY_SIZE(lcl_iovec), 1, 1, 0, 0,
2, {SEGM1_BASE, SEGM2_BASE}, {SIZE_1, SIZE_2} };
struct print_iov_arg rmt_arg = { ARRAY_SIZE(rmt_iovec), 1 };
struct print_iov_arg bogus_arg_cut =
{ ARRAY_SIZE(bogus_iovec) - 2, 1, 0, 1 };
struct print_iov_arg lcl_arg_cut =
{ ARRAY_SIZE(lcl_iovec) - 2, 1, 1, 1, 0, 2,
{SEGM1_BASE + SIZE_11 + SIZE_12, SEGM2_BASE},
{SIZE_13, SIZE_2} };
struct print_iov_arg rmt_arg_cut =
{ ARRAY_SIZE(rmt_iovec) - 2, 1 };
fill_memory_ex(data1_out, SIZE_1, SEGM1_BASE, SIZE_1);
fill_memory_ex(data2_out, SIZE_2, SEGM2_BASE, SIZE_2);
do_call(bogus_pid, (kernel_ulong_t) (uintptr_t) ARG_STR(NULL),
bogus_iovcnt1, (kernel_ulong_t) (uintptr_t) ARG_STR(NULL),
bogus_iovcnt2, bogus_flags, NULL);
do_call(my_pid, ptr_cast(bogus_iov + ARRAY_SIZE(bogus_iovec)),
"[]", 0, ptr_cast(in_iov + ARRAY_SIZE(in_iovec)), "[]",
0, 0, NULL);
do_call(my_pid, ptr_cast(bogus_iov + ARRAY_SIZE(bogus_iovec)), NULL,
bogus_iovcnt1, ptr_cast(in_iov + ARRAY_SIZE(in_iovec)), NULL,
bogus_iovcnt2, 0, print_iov);
do_call(my_pid, ptr_cast(bogus_iov), (char *) &bogus_arg,
ARRAY_SIZE(bogus_iovec), ptr_cast(rmt_iov + 2),
(char *) &rmt_arg_cut, ARRAY_SIZE(rmt_iovec) - 2, 0, print_iov);
#if !OP_WR
lcl_arg.check_rc = 1;
lcl_arg_cut.check_rc = 1;
#endif
do_call(my_pid, ptr_cast(lcl_iov + 2), (char *) &lcl_arg_cut,
ARRAY_SIZE(lcl_iovec) - 1, ptr_cast(bogus_iov + 2),
(char *) &bogus_arg_cut, ARRAY_SIZE(bogus_iovec) - 1, 0,
print_iov);
lcl_arg_cut.addr_term = 0;
rmt_arg_cut.addr_term = 1;
rmt_arg_cut.count = 5;
do_call(my_pid, ptr_cast(lcl_iov + 2), (char *) &lcl_arg_cut,
ARRAY_SIZE(lcl_iovec) - 2, ptr_cast(rmt_iov + 1),
(char *) &rmt_arg_cut, ARRAY_SIZE(rmt_iovec), 0, print_iov);
/* Correct call */
do_call(my_pid, ptr_cast(lcl_iov), (char *) &lcl_arg,
ARRAY_SIZE(lcl_iovec), ptr_cast(rmt_iov), (char *) &rmt_arg,
ARRAY_SIZE(rmt_iovec), 0, print_iov);
puts("+++ exited with 0 +++");
return 0;
}