From: Rémi Bernon rbernon@codeweavers.com
--- loader/main.c | 3 ++- loader/preloader.c | 38 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+), 1 deletion(-)
diff --git a/loader/main.c b/loader/main.c index c258e025183..5a208cc048c 100644 --- a/loader/main.c +++ b/loader/main.c @@ -38,7 +38,8 @@
extern char **environ;
-/* the preloader will set this variable */ +/* the preloader will set these variables */ +__attribute((visibility("default"))) struct r_debug *wine_r_debug = NULL; const __attribute((visibility("default"))) struct wine_preload_info *wine_main_preload_info = NULL;
/* canonicalize path and return its directory name */ diff --git a/loader/preloader.c b/loader/preloader.c index d0551bae63a..016f1def249 100644 --- a/loader/preloader.c +++ b/loader/preloader.c @@ -1387,6 +1387,32 @@ static void set_process_name( int argc, char *argv[] ) for (i = 1; i < argc; i++) argv[i] -= off; }
+/* GDB integration, _dl_debug_state is *required* for GDB to hook the preloader */ +__attribute((visibility("default"))) void _dl_debug_state(void) {} +static struct r_debug_extended r_debug = {.base = {.r_version = 2}}; + +/* sets the preloader r_debug address into DT_DEBUG */ +static void init_r_debug( struct wld_auxv *av ) +{ + ElfW(Phdr) *phdr, *ph; + ElfW(Dyn) *dyn = NULL; + char *l_addr; + int phnum; + + if (!(phnum = get_auxiliary( av, AT_PHNUM, 0 ))) return; + if (!(phdr = (void *)get_auxiliary( av, AT_PHDR, 0 ))) return; + l_addr = (char *)phdr - sizeof(ElfW(Ehdr)); + + for (ph = phdr; ph < &phdr[phnum]; ++ph) if (ph->p_type == PT_DYNAMIC) break; + if (ph >= &phdr[phnum]) return; + + dyn = (void *)(ph->p_vaddr + l_addr); + while (dyn->d_tag != DT_DEBUG) dyn++; + + r_debug.base.r_ldbase = (ElfW(Addr))l_addr; + r_debug.base.r_brk = (ElfW(Addr))_dl_debug_state; + if (dyn->d_tag == DT_DEBUG) dyn->d_un.d_ptr = (uintptr_t)&r_debug; +}
/* * wld_start @@ -1403,6 +1429,7 @@ void* wld_start( void **stack ) struct wld_auxv new_av[8], delete_av[3], *av; struct wld_link_map main_binary_map, ld_so_map; struct wine_preload_info **wine_main_preload_info; + struct r_debug *ld_so_r_debug, **wine_r_debug;
pargc = *stack; argv = (char **)pargc + 1; @@ -1432,6 +1459,8 @@ void* wld_start( void **stack ) dump_auxiliary( av ); #endif
+ init_r_debug( av ); + /* reserve memory that Wine needs */ if (reserve) preload_reserve( reserve ); for (i = 0; preload_info[i].size; i++) @@ -1470,6 +1499,15 @@ void* wld_start( void **stack ) interp = (char *)main_binary_map.l_addr + main_binary_map.l_interp; map_so_lib( interp, &ld_so_map );
+ /* expose ld.so _r_debug as a separate namespace in r_next */ + ld_so_r_debug = find_symbol( &ld_so_map, "_r_debug", STT_OBJECT ); + if (ld_so_r_debug) r_debug.r_next = (struct r_debug_extended *)ld_so_r_debug; + else wld_printf( "_r_debug not found in ld.so\n" ); + + wine_r_debug = find_symbol( &main_binary_map, "wine_r_debug", STT_OBJECT ); + if (wine_r_debug) *wine_r_debug = &r_debug.base; + else wld_printf( "wine_r_debug not found\n" ); + /* store pointer to the preload info into the appropriate main binary variable */ wine_main_preload_info = find_symbol( &main_binary_map, "wine_main_preload_info", STT_OBJECT ); if (wine_main_preload_info) *wine_main_preload_info = preload_info;