Calling an IFUNC function defined in unrelocated executable also leads to
segfault. Issue a fatal error message when calling IFUNC function defined
in the unrelocated executable from a shared library.
On x86, ifuncmain6pie failed with:
[hjl@gnu-cfl-2 build-i686-linux]$ ./elf/ifuncmain6pie --direct
./elf/ifuncmain6pie: IFUNC symbol 'foo' referenced in '/export/build/gnu/tools-build/glibc-32bit/build-i686-linux/elf/ifuncmod6.so' is defined in the executable and creates an unsatisfiable circular dependency.
[hjl@gnu-cfl-2 build-i686-linux]$ readelf -rW elf/ifuncmod6.so | grep foo
00003ff4 00000706 R_386_GLOB_DAT
0000400c foo_ptr
00003ff8 00000406 R_386_GLOB_DAT
00000000 foo
0000400c 00000401 R_386_32
00000000 foo
[hjl@gnu-cfl-2 build-i686-linux]$
Remove non-JUMP_SLOT relocations against foo in ifuncmod6.so, which
trigger the circular IFUNC dependency, and build ifuncmain6pie with
-Wl,-z,lazy.
(cherry picked from commits
6ea5b57afa5cdc9ce367d2b69a2cebfb273e4617
and
7137d682ebfcb6db5dfc5f39724718699922f06c)
[18035] Fix pldd hang
[19444] build failures with -O1 due to -Wmaybe-uninitialized
[20018] getaddrinfo should reject IP addresses with trailing characters
+ [20019] NULL pointer dereference in libc.so.6 IFUNC due to uninitialized GOT
[20209] localedata: Spelling mistake for Sunday in Greenlandic kl_GL
[20568] Fix crash in _IO_wfile_sync
[22927] libanl: properly cleanup if first helper thread creation failed
CFLAGS-ifuncmain6pie.c += $(pie-ccflag)
CFLAGS-ifuncmain7pie.c += $(pie-ccflag)
+LDFLAGS-ifuncmain6pie = -Wl,-z,lazy
+
$(objpfx)ifuncmain1pie: $(objpfx)ifuncmod1.so
$(objpfx)ifuncmain1staticpie: $(objpfx)ifuncdep1pic.o
$(objpfx)ifuncmain1vispie: $(objpfx)ifuncmod1.so
#include "ifunc-sel.h"
typedef int (*foo_p) (void);
-extern foo_p foo_ptr;
static int
one (void)
}
extern int foo (void);
-extern foo_p get_foo (void);
+extern int call_foo (void);
extern foo_p get_foo_p (void);
-foo_p my_foo_ptr = foo;
+foo_p foo_ptr = foo;
int
main (void)
{
foo_p p;
- p = get_foo ();
- if (p != foo)
- abort ();
- if ((*p) () != -30)
+ if (call_foo () != -30)
abort ();
p = get_foo_p ();
if (foo_ptr != foo)
abort ();
- if (my_foo_ptr != foo)
- abort ();
if ((*foo_ptr) () != -30)
abort ();
- if ((*my_foo_ptr) () != -30)
- abort ();
if (foo () != -30)
abort ();
typedef int (*foo_p) (void);
-foo_p foo_ptr = foo;
+extern foo_p foo_ptr;
foo_p
get_foo_p (void)
return foo_ptr;
}
-foo_p
-get_foo (void)
+int
+call_foo (void)
{
- return foo;
+ return foo ();
}
{
# ifndef RTLD_BOOTSTRAP
if (sym_map != map
- && sym_map->l_type != lt_executable
&& !sym_map->l_relocated)
{
const char *strtab
= (const char *) D_PTR (map, l_info[DT_STRTAB]);
- _dl_error_printf ("\
+ if (sym_map->l_type == lt_executable)
+ _dl_fatal_printf ("\
+%s: IFUNC symbol '%s' referenced in '%s' is defined in the executable \
+and creates an unsatisfiable circular dependency.\n",
+ RTLD_PROGNAME, strtab + refsym->st_name,
+ map->l_name);
+ else
+ _dl_error_printf ("\
%s: Relink `%s' with `%s' for IFUNC symbol `%s'\n",
- RTLD_PROGNAME, map->l_name,
- sym_map->l_name,
- strtab + refsym->st_name);
+ RTLD_PROGNAME, map->l_name,
+ sym_map->l_name,
+ strtab + refsym->st_name);
}
# endif
value = ((Elf32_Addr (*) (void)) value) ();
{
# ifndef RTLD_BOOTSTRAP
if (sym_map != map
- && sym_map->l_type != lt_executable
&& !sym_map->l_relocated)
{
const char *strtab
= (const char *) D_PTR (map, l_info[DT_STRTAB]);
- _dl_error_printf ("\
+ if (sym_map->l_type == lt_executable)
+ _dl_fatal_printf ("\
+%s: IFUNC symbol '%s' referenced in '%s' is defined in the executable \
+and creates an unsatisfiable circular dependency.\n",
+ RTLD_PROGNAME, strtab + refsym->st_name,
+ map->l_name);
+ else
+ _dl_error_printf ("\
%s: Relink `%s' with `%s' for IFUNC symbol `%s'\n",
- RTLD_PROGNAME, map->l_name,
- sym_map->l_name,
- strtab + refsym->st_name);
+ RTLD_PROGNAME, map->l_name,
+ sym_map->l_name,
+ strtab + refsym->st_name);
}
# endif
value = ((ElfW(Addr) (*) (void)) value) ();