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From:
George Koehler <kernigh@gmail.com>
Subject:
macppc ld.so: move check for unsupported PLT
To:
tech@openbsd.org
Date:
Fri, 21 Aug 2026 18:00:55 -0400

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Pike from https://pike.lysator.liu.se gave a strange error on macppc,

$ pike --features
ld.so: pike: unsupported insecure BSS PLT object
Killed

The PLT is for relocating function calls.  The old BSS PLT for powerpc
is extinct.  Pike used ld -nostartmodules to link a module with no
function calls.  This module has no PLT, and ld.so confused the
absence of a PLT with the presence of a BSS PLT.  This diff fixes it
by moving the check for the secure PLT (if PPC_GOT is nonzero) after
the check for any kind of PLT (if PLTREL is RELA).  Now pike doesn't
die, but if I make a BSS PLT, it still dies:

$ cc -fuse-ld=bfd -Wl,--bss-plt -o here here.c
$ ./here
ld.so: here: unsupported insecure BSS PLT object
Killed

ok to commit?
--gkoehler

Index: powerpc/rtld_machine.c
===================================================================
RCS file: /cvs/src/libexec/ld.so/powerpc/rtld_machine.c,v
diff -u -p -r1.73 rtld_machine.c
--- powerpc/rtld_machine.c	16 Jul 2026 11:21:37 -0000	1.73
+++ powerpc/rtld_machine.c	21 Aug 2026 01:59:18 -0000
@@ -74,9 +74,6 @@ _dl_md_reloc(elf_object_t *object, int r
 	if (relrel > numrela)
 		_dl_die("relcount > numrel: %ld > %d", relrel, numrela);
 
-	if (object->Dyn.info[DT_PROC(DT_PPC_GOT)] == 0)
-		_dl_die("unsupported insecure BSS PLT object");
-
 	/* tight loop for leading RELATIVE relocs */
 	for (i = 0; i < relrel; i++, relas++) {
 		Elf_Addr *r_addr;
@@ -273,6 +270,9 @@ _dl_md_reloc_got(elf_object_t *object, i
 
 	if (object->Dyn.info[DT_PLTREL] != DT_RELA)
 		return 0;
+
+	if (object->Dyn.info[DT_PROC(DT_PPC_GOT)] == 0)
+		_dl_die("unsupported insecure BSS PLT object");
 
 	if (!lazy) {
 		fails = _dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);