ntdll: Fix ELF initializer address calculations on FreeBSD.

dlinfo() doesn't conform to a standard, each platform implements in differently,
if at all. On GNU and NetBSD its l_addr field returned is the "relocbase",
the relative offset between addresses wanted by the file and addresses obtained
in memory (==0 when no relocation occurred), which we add to d_un.d_ptr to
obtain the memory address where the initializer is. On FreeBSD (and possibly
Solaris) this won't work, as l_addr is the "mapbase" instead, the absolute
starting memory address where the binary was loaded, resulting in wrong
calculations and crashes on startup as we call into wrong addresses.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=49139
Signed-off-by: Damjan Jovanovic <damjan.jov@gmail.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
This commit is contained in:
Damjan Jovanovic 2020-05-17 12:49:08 +02:00 committed by Alexandre Julliard
parent 0f31e48e9b
commit 0fd3f0266e
1 changed files with 36 additions and 4 deletions

View File

@ -1317,6 +1317,35 @@ static void call_tls_callbacks( HMODULE module, UINT reason )
}
}
#ifdef __FreeBSD__
/* The PT_LOAD segments are sorted in increasing order, and the first
* starts at the beginning of the ELF file. By parsing the file, we can
* find that first PT_LOAD segment, from which we can find the base
* address it wanted, and knowing mapbase where the binary was actually
* loaded, use them to work out the relocbase offset. */
static BOOL get_relocbase(caddr_t mapbase, caddr_t *relocbase)
{
Elf_Half i;
#ifdef _WIN64
const Elf64_Ehdr *elf_header = (Elf64_Ehdr*) mapbase;
#else
const Elf32_Ehdr *elf_header = (Elf32_Ehdr*) mapbase;
#endif
const Elf_Phdr *prog_header = (const Elf_Phdr *)(mapbase + elf_header->e_phoff);
for (i = 0; i < elf_header->e_phnum; i++)
{
if (prog_header->p_type == PT_LOAD)
{
caddr_t desired_base = (caddr_t)((prog_header->p_vaddr / prog_header->p_align) * prog_header->p_align);
*relocbase = (caddr_t) (mapbase - desired_base);
return TRUE;
}
prog_header++;
}
return FALSE;
}
#endif
/*************************************************************************
* call_constructors
@ -1339,14 +1368,17 @@ static void call_constructors( WINE_MODREF *wm )
if (dlinfo( wm->so_handle, RTLD_DI_LINKMAP, &map ) == -1) return;
for (dyn = map->l_ld; dyn->d_tag; dyn++)
{
#define GET_PTR(base,ptr) ((ptr) > (base) ? (ptr) : (base) + (ptr))
caddr_t relocbase = (caddr_t)map->l_addr;
#ifdef __FreeBSD__ /* FreeBSD doesn't relocate l_addr */
if (!get_relocbase(map->l_addr, &relocbase)) return;
#endif
switch (dyn->d_tag)
{
case 0x60009990: init_array = (void *)GET_PTR( map->l_addr, dyn->d_un.d_ptr ); break;
case 0x60009990: init_array = (void *)(relocbase + dyn->d_un.d_val); break;
case 0x60009991: init_arraysz = dyn->d_un.d_val; break;
case 0x60009992: init_func = (void *)GET_PTR( map->l_addr, dyn->d_un.d_ptr ); break;
case 0x60009992: init_func = (void *)(relocbase + dyn->d_un.d_val); break;
}
#undef GET_PTR
}
TRACE( "%s: got init_func %p init_array %p %lu\n", debugstr_us( &wm->ldr.BaseDllName ),