mirror of
https://github.com/tobast/libunwind-eh_elf.git
synced 2024-06-26 11:21:44 +02:00
b56375e76a
Currently, libunwind allocates several PATH_MAX entries on stack, while trying to find a binary via /proc/.../maps. However stack space may be at premium (especially when sigaltstack is used), and PATH_MAX on Linux is 4096, while SIGSTKSZ is only 8192 on x86. Attached patch eliminates multiple PATH_MAX stack allocations, and simplifies code in maps_next, at the cost of being unable to do anything if we can't mmap one page. It appears to me that under such low-memory conditions, libunwind will fail shortly elsewhere anyway. This patch also disables more of debug_frame-handling code when CONFIG_DEBUG_FRAME is undefined. Tested on Linux/x86_64 with and without CONFIG_DEBUG_FRAME, no regressions.
64 lines
1.8 KiB
C
64 lines
1.8 KiB
C
/* libunwind - a platform-independent unwind library
|
|
Copyright (C) 2003-2005 Hewlett-Packard Co
|
|
Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
|
|
|
|
This file is part of libunwind.
|
|
|
|
Permission is hereby granted, free of charge, to any person obtaining
|
|
a copy of this software and associated documentation files (the
|
|
"Software"), to deal in the Software without restriction, including
|
|
without limitation the rights to use, copy, modify, merge, publish,
|
|
distribute, sublicense, and/or sell copies of the Software, and to
|
|
permit persons to whom the Software is furnished to do so, subject to
|
|
the following conditions:
|
|
|
|
The above copyright notice and this permission notice shall be
|
|
included in all copies or substantial portions of the Software.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
|
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
|
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
|
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
|
|
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
|
|
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
|
|
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
|
|
|
|
#ifndef UNW_REMOTE_ONLY
|
|
|
|
#include <limits.h>
|
|
#include <stdio.h>
|
|
|
|
#include "libunwind_i.h"
|
|
#include "os-linux.h"
|
|
|
|
PROTECTED int
|
|
tdep_get_elf_image (struct elf_image *ei, pid_t pid, unw_word_t ip,
|
|
unsigned long *segbase, unsigned long *mapoff)
|
|
{
|
|
struct map_iterator mi;
|
|
int found = 0, rc;
|
|
unsigned long hi;
|
|
|
|
if (maps_init (&mi, pid) < 0)
|
|
return -1;
|
|
|
|
while (maps_next (&mi, segbase, &hi, mapoff))
|
|
if (ip >= *segbase && ip < hi)
|
|
{
|
|
found = 1;
|
|
break;
|
|
}
|
|
|
|
if (!found)
|
|
{
|
|
maps_close (&mi);
|
|
return -1;
|
|
}
|
|
|
|
rc = elf_map_image (ei, mi.path);
|
|
maps_close (&mi);
|
|
return rc;
|
|
}
|
|
|
|
#endif /* UNW_REMOTE_ONLY */
|