Paranoia about mprotect, mprotect page aligned regions for got and plt.

1 files changed, 37 insertions, 15 deletions

diff --git a/libexec/ld.so/powerpc/rtld_machine.c b/libexec/ld.so/powerpc/rtld_machine.c
index 8c5b1e89535..2a040336a6d 100644
--- a/libexec/ld.so/powerpc/rtld_machine.c
+++ b/libexec/ld.so/powerpc/rtld_machine.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtld_machine.c,v 1.23 2003/02/15 00:30:16 drahn Exp $ */
+/*	$OpenBSD: rtld_machine.c,v 1.24 2003/02/15 22:39:13 drahn Exp $ */
 
 /*
  * Copyright (c) 1999 Dale Rahn
@@ -448,9 +448,10 @@ _dl_printf(" found other symbol at %x size %d\n",
 void
 _dl_md_reloc_got(elf_object_t *object, int lazy)
 {
-	Elf32_Addr *pltresolve;
-	Elf32_Addr *first_rela;
-	Elf32_Rela  *relas;
+	Elf_Addr *pltresolve;
+	Elf_Addr *first_rela;
+	Elf_RelA *relas;
+	Elf_Addr  plt_addr;
 	int	numrela;
 	int i;
 	int index;
@@ -461,6 +462,8 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	if (object->Dyn.info[DT_PLTREL] != DT_RELA)
 		return;
 
+	object->got_addr = NULL;
+	object->got_size = 0;
 	this = NULL;
 	ooff = _dl_find_symbol("__got_start", object, &this,
 	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
@@ -475,20 +478,38 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 	if (this != NULL)
 		object->got_size = ooff + this->st_value  - object->got_addr;
 
+	plt_addr = 0;
+	object->plt_size = 0;
 	this = NULL;
 	ooff = _dl_find_symbol("__plt_start", object, &this,
 	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
 	    NULL);
 	if (this != NULL)
-		object->plt_addr = ooff + this->st_value;
+		plt_addr = ooff + this->st_value;
 
 	this = NULL;
 	ooff = _dl_find_symbol("__plt_end", object, &this,
 	    SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT,
 	    NULL);
 	if (this != NULL)
-		object->plt_size = ooff + this->st_value  - object->plt_addr;
-
+		object->plt_size = ooff + this->st_value  - plt_addr;
+
+	if (object->got_addr == NULL)
+		object->got_start = NULL;
+	else {
+		object->got_start = ELF_TRUNC(object->got_addr, _dl_pagesz);
+		object->got_size += object->got_addr - object->got_start;
+		object->got_size = ELF_ROUND(object->got_size, _dl_pagesz);
+	}
+	if (plt_addr == NULL)
+		object->plt_start = NULL;
+	else {
+		object->plt_start = ELF_TRUNC(plt_addr, _dl_pagesz);
+		object->plt_size += plt_addr - object->plt_start;
+		object->plt_size = ELF_ROUND(object->plt_size, _dl_pagesz);
+	}
+		
+	
 	if (!lazy) {
 		_dl_md_reloc(object, DT_JMPREL, DT_PLTRELSZ);
 		return;
@@ -518,13 +539,14 @@ _dl_md_reloc_got(elf_object_t *object, int lazy)
 		_dl_dcbf(&r_addr[0]);
 		_dl_dcbf(&r_addr[2]);
 	}
-	if (object->got_addr != NULL && object->got_size != 0) {
-		_dl_mprotect((void*)object->got_addr, object->got_size,
+	if (object->got_size != 0) {
+
+		_dl_mprotect((void*)object->got_start, object->got_size,
 		    PROT_READ|PROT_EXEC); /* only PPC is PROT_EXE */
 		_dl_syncicache((void*)object->got_addr, 4);
 	}
-	if (object->plt_addr != NULL && object->plt_size != 0)
-		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+	if (object->plt_size != 0)
+		_dl_mprotect((void*)object->plt_start, object->plt_size,
 		    PROT_READ|PROT_EXEC);
 }
 
@@ -560,10 +582,10 @@ _dl_bind(elf_object_t *object, int reloff)
 	}
 
 	/* if PLT is protected, allow the write */
-	if (object->plt_addr != NULL && object->plt_size != 0)  {
+	if (object->plt_size != 0)  {
 		sigfillset(&nmask);
 		_dl_sigprocmask(SIG_BLOCK, &nmask, &omask);
-		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+		_dl_mprotect((void*)object->plt_start, object->plt_size,
 		    PROT_READ|PROT_WRITE|PROT_EXEC);
 	}
 
@@ -611,8 +633,8 @@ _dl_bind(elf_object_t *object, int reloff)
 	}
 
 	/* if PLT is (to be protected, change back to RO/X */
-	if (object->plt_addr != NULL && object->plt_size != 0) {
-		_dl_mprotect((void*)object->plt_addr, object->plt_size,
+	if (object->plt_size != 0) {
+		_dl_mprotect((void*)object->plt_start, object->plt_size,
 		    PROT_READ|PROT_EXEC); /* only PPC is PROT_EXE */
 		_dl_sigprocmask(SIG_SETMASK, &omask, NULL);
 	}