1 /* 2 * Copyright (c) 2018 The strace developers. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include "defs.h" 29 30 /* 31 * Fetch indirect syscall arguments that are provided as an array. 32 * Return a pointer to a static array of kernel_ulong_t elements, 33 * or NULL in case of fetch failure. 34 */ 35 kernel_ulong_t * 36 fetch_indirect_syscall_args(struct tcb *const tcp, 37 const kernel_ulong_t addr, 38 const unsigned int n_args) 39 { 40 static kernel_ulong_t u_arg[MAX_ARGS]; 41 42 if (current_wordsize == sizeof(*u_arg)) { 43 if (umoven(tcp, addr, sizeof(*u_arg) * n_args, u_arg)) 44 return NULL; 45 } else { 46 uint32_t narrow_arg[ARRAY_SIZE(u_arg)]; 47 48 if (umoven(tcp, addr, sizeof(*narrow_arg) * n_args, narrow_arg)) 49 return NULL; 50 for (unsigned int i = 0; i < n_args; ++i) 51 u_arg[i] = narrow_arg[i]; 52 } 53 54 return u_arg; 55 } 56
