m2-internship/libunwind-eh_elf
1
0
Fork 0
mirror of https://github.com/tobast/libunwind-eh_elf.git synced 2024-11-22 07:37:38 +01:00
Code Issues Releases Activity

Make .debug_frame support optional.

Browse source 
Because these code paths use malloc and stdio, they could
cause deadlocks when we try to unwind stack from inside malloc.
This commit is contained in:
Arun Sharma 2009-03-16 21:21:58 -07:00
parent 638302ed73
commit a2c27a4ab7
2 changed files with 24 additions and 20 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
configure.in
View file

@ -124,6 +124,10 @@ if test x$enable_cxx_exceptions = xyes; then
fi
AM_CONDITIONAL([SUPPORT_CXX_EXCEPTIONS], [test x$enable_cxx_exceptions = xyes])
AC_ARG_ENABLE(debug_frame,
[ --enable-debug-frame Load the ".debug_frame" section if available],
[enable_debug_frame=$enableval], [enable_debug_frame=yes])
AM_CONDITIONAL([CONFIG_DEBUG_FRAME], [test x$enable_debug_frame = xyes])
LIBUNWIND___THREAD
save_LDFLAGS="$LDFLAGS"

40
src/dwarf/Gfind_proc_info-lsb.c
View file

@ -92,6 +92,7 @@ linear_search (unw_addr_space_t as, unw_word_t ip,
return -UNW_ENOINFO;
}
#ifdef CONFIG_DEBUG_FRAME
/* Load .debug_frame section from FILE. Allocates and returns space
in *BUF, and sets *BUFSIZE to its size. IS_LOCAL is 1 if using the
local process, in which case we can search the system debug file
@ -132,7 +133,7 @@ load_debug_frame (const char *file, char **buf, size_t *bufsize, int is_local)
sec_hdrs = calloc (ehdr.e_shnum, sizeof (Elf_W (Shdr)));
fread (sec_hdrs, sizeof (Elf_W (Shdr)), ehdr.e_shnum, f);
Debug (4, "loading string table of size %d\n",
Debug (4, "loading string table of size %zd\n",
sec_hdrs[shstrndx].sh_size);
stringtab = malloc (sec_hdrs[shstrndx].sh_size);
fseek (f, sec_hdrs[shstrndx].sh_offset, SEEK_SET);
@ -150,7 +151,7 @@ load_debug_frame (const char *file, char **buf, size_t *bufsize, int is_local)
fseek (f, sec_hdrs[i].sh_offset, SEEK_SET);
fread (*buf, 1, *bufsize, f);
Debug (4, "read %d bytes of .debug_frame from offset %d\n",
Debug (4, "read %zd bytes of .debug_frame from offset %zd\n",
*bufsize, sec_hdrs[i].sh_offset);
}
else if (is_local >= 0 && strcmp (secname, ".gnu_debuglink") == 0)
@ -161,7 +162,7 @@ load_debug_frame (const char *file, char **buf, size_t *bufsize, int is_local)
fseek (f, sec_hdrs[i].sh_offset, SEEK_SET);
fread (linkbuf, 1, linksize, f);
Debug (4, "read %d bytes of .gnu_debuglink from offset %d\n",
Debug (4, "read %zd bytes of .gnu_debuglink from offset %zd\n",
*bufsize, sec_hdrs[i].sh_offset);
}
}
@ -220,36 +221,37 @@ load_debug_frame (const char *file, char **buf, size_t *bufsize, int is_local)
return 0;
}
#else
static int
load_debug_frame (const char *file, char **buf, size_t *bufsize, int is_local)
{
return 1;
}
#endif /* CONFIG_DEBUG_FRAME */
/* Locate the binary which originated the contents of address ADDR. Return
the name of the binary in *name (which is allocated on the heap, and must
be freed by the caller). Returns 0 if a binary is successfully found, or 1
if an error occurs. */
the name of the binary in *name (space is allocated by the caller)
Returns 0 if a binary is successfully found, or 1 if an error occurs. */
static int
find_binary_for_address (unw_word_t ip, char **name)
find_binary_for_address (unw_word_t ip, char *name, size_t name_size)
{
#ifdef __linux
struct map_iterator mi;
char path[PATH_MAX];
int found = 0;
int pid = getpid ();
unsigned long segbase, mapoff, hi;
maps_init (&mi, pid);
while (maps_next (&mi, &segbase, &hi, &mapoff, path, sizeof (path)))
while (maps_next (&mi, &segbase, &hi, &mapoff, name, name_size))
if (ip >= segbase && ip < hi)
{
found = 1;
break;
}
maps_close (&mi);
if (found)
{
*name = strdup (path);
return 0;
}
return ~found;
#endif
return 1;
@ -263,7 +265,8 @@ locate_debug_info (unw_addr_space_t as, struct dl_phdr_info *info,
unw_word_t addr, const char *dlname)
{
struct unw_debug_frame_list *w, *fdesc = 0;
char *name = 0;
char path[PATH_MAX];
char *name = path;
int err;
uint64_t start = 0, end = 0;
char *buf;
@ -284,7 +287,7 @@ locate_debug_info (unw_addr_space_t as, struct dl_phdr_info *info,
if (strcmp (dlname, "") == 0)
{
err = find_binary_for_address (addr, &name);
err = find_binary_for_address (addr, name, sizeof(path));
if (err)
{
Debug (15, "tried to locate binary for 0x%" PRIx64 ", but no luck\n",
@ -334,9 +337,6 @@ locate_debug_info (unw_addr_space_t as, struct dl_phdr_info *info,
as->debug_frames = fdesc;
}
if (name && name != dlname)
free (name);
return fdesc;
}