1 /*
2 * Copyright (c) 2010 Konstantin Belousov <kib@freebsd.org>
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. Neither the name of the author nor the names of any co-contributors
11 * may be used to endorse or promote products derived from this software
12 * without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29 #include <sys/types.h>
30 #include <sys/mman.h>
31 #include <sys/resource.h>
32 #include <sys/sysctl.h>
33 #include <link.h>
34 #include <stddef.h>
35
36 int __elf_phdr_match_addr(struct dl_phdr_info *, void *);
37 void __pthread_map_stacks_exec(void);
38
39 int
__elf_phdr_match_addr(struct dl_phdr_info * phdr_info,void * addr)40 __elf_phdr_match_addr(struct dl_phdr_info *phdr_info, void *addr)
41 {
42 const Elf_Phdr *ph;
43 int i;
44
45 for (i = 0; i < phdr_info->dlpi_phnum; i++) {
46 ph = &phdr_info->dlpi_phdr[i];
47 if (ph->p_type != PT_LOAD || (ph->p_flags & PF_X) == 0)
48 continue;
49 if (phdr_info->dlpi_addr + ph->p_vaddr <= (uintptr_t)addr &&
50 (uintptr_t)addr + sizeof(addr) < phdr_info->dlpi_addr +
51 ph->p_vaddr + ph->p_memsz)
52 break;
53 }
54 return (i != phdr_info->dlpi_phnum);
55 }
56
57 #pragma weak __pthread_map_stacks_exec
58 void
__pthread_map_stacks_exec(void)59 __pthread_map_stacks_exec(void)
60 {
61 int mib[2];
62 struct rlimit rlim;
63 u_long usrstack;
64 size_t len;
65
66 mib[0] = CTL_KERN;
67 mib[1] = KERN_USRSTACK;
68 len = sizeof(usrstack);
69 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), &usrstack, &len, NULL, 0)
70 == -1)
71 return;
72 if (getrlimit(RLIMIT_STACK, &rlim) == -1)
73 return;
74 mprotect((void *)(uintptr_t)(usrstack - rlim.rlim_cur),
75 rlim.rlim_cur, _rtld_get_stack_prot());
76 }
77
78