CVS commit: src/lib/libexecinfo

[Christos Zoulas]

Module Name:    src
Committed By:   christos
Date:           Wed Apr 20 14:00:16 UTC 2016

Modified Files:
        src/lib/libexecinfo: symtab.c

Log Message:
Don't subtract base if not pie.


To generate a diff of this commit:
cvs rdiff -u -r1.4 -r1.5 src/lib/libexecinfo/symtab.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/lib/libexecinfo/symtab.c
diff -u src/lib/libexecinfo/symtab.c:1.4 src/lib/libexecinfo/symtab.c:1.5
--- src/lib/libexecinfo/symtab.c:1.4	Mon Apr 11 11:30:18 2016
+++ src/lib/libexecinfo/symtab.c	Wed Apr 20 10:00:16 2016
@@ -1,4 +1,4 @@
-/*	$NetBSD: symtab.c,v 1.4 2016/04/11 15:30:18 christos Exp $	*/
+/*	$NetBSD: symtab.c,v 1.5 2016/04/20 14:00:16 christos Exp $	*/
 
 /*-
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -29,12 +29,13 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: symtab.c,v 1.4 2016/04/11 15:30:18 christos Exp $");
+__RCSID("$NetBSD: symtab.c,v 1.5 2016/04/20 14:00:16 christos Exp $");
 
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <err.h>
 #include <dlfcn.h>
 
@@ -58,6 +59,7 @@ struct symbol {
 struct symtab {
 	size_t nsymbols;
 	struct symbol *symbols;
+	bool ispie;
 };
 
 static int
@@ -85,6 +87,7 @@ symtab_create(int fd, int bind, int type
 	Elf *elf;
 	symtab_t *st;
 	Elf_Scn *scn = NULL;
+	GElf_Ehdr ehdr;
 
 	if (elf_version(EV_CURRENT) == EV_NONE) {
 		warnx("Elf Library is out of date.");
@@ -102,6 +105,13 @@ symtab_create(int fd, int bind, int type
 		elf_end(elf);
 		return NULL;
 	}
+	if (gelf_getehdr(elf, &ehdr) == NULL) {
+		warnx("Error getting ELF Ehdr");
+		elf_end(elf);
+		return NULL;
+	}
+
+	st->ispie = ehdr.e_type == ET_DYN;
 
 	while ((scn = elf_nextscn(elf, scn)) != NULL) {
 		GElf_Shdr shdr;
@@ -176,12 +186,14 @@ symtab_find(const symtab_t *st, const vo
 	size_t hi = ns;
 	size_t lo = 0;
 	size_t mid = ns / 2;
-	uintptr_t dd, sd, me = (uintptr_t)p - (uintptr_t)dli->dli_fbase;
-	uintptr_t ad = (uintptr_t)dli->dli_saddr - (uintptr_t)dli->dli_fbase;
+	uintptr_t fbase = st->ispie ? (uintptr_t)dli->dli_fbase : 0;
+	uintptr_t dd, sd, me = (uintptr_t)p - fbase;
+	uintptr_t ad = (uintptr_t)dli->dli_saddr - fbase;
 
 #ifdef SYMTAB_DEBUG
-	fprintf(stderr, "%s: [fbase=%p, saddr=%p, me=%#jx]\n", __func__,
-	    dli->dli_fbase, dli->dli_saddr, (uintmax_t)me);
+	fprintf(stderr, "%s: [fbase=%#jx, saddr=%p, me=%#jx ad=%#jx]\n",
+	    __func__, (uintmax_t)fbase, dli->dli_saddr, (uintmax_t)me,
+	    (uintmax_t)ad);
 #endif
 	for (;;) {
 		if (s[mid].st_value < me)
@@ -202,14 +214,14 @@ symtab_find(const symtab_t *st, const vo
 		dli->dli_saddr = (void *)s[mid].st_value;
 		dli->dli_sname = s[mid].st_name;
 #ifdef SYMTAB_DEBUG
-		fprintf(stderr, "%s: %p -> [%p, %s]\n", __func__,
-		    p, dli->dli_saddr, dli->dli_sname);
+		fprintf(stderr, "%s: me=%#jx -> [%#jx, %s]\n", __func__,
+		    (uintmax_t)me, (uintmax_t)sd, dli->dli_sname);
 #endif
 	}
 #ifdef SYMTAB_DEBUG
 	else
-		fprintf(stderr, "%s: %p -> [%p, ***]\n", __func__,
-		    p, dli->dli_saddr);
+		fprintf(stderr, "%s: %#jx -> [%#jx, ***]\n", __func__,
+		    (uintmax_t)me, (uintmax_t)sd);
 #endif
 	return 1;
 }