From: Rich Felker <dalias@aerifal.cx>
Date: Thu, 4 Jun 2015 15:45:17 +0000 (-0400)
Subject: fix dynamic linker regression processing R_*_NONE type relocations
X-Git-Tag: v1.1.10~1
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=b6a6cd703ffefa6352249fb01f4da28d85d17306;p=oweals%2Fmusl.git

fix dynamic linker regression processing R_*_NONE type relocations

commit f3ddd173806fd5c60b3f034528ca24542aecc5b9 inadvertently removed
the early check for "none" type relocations, causing the address
dso->base+0 to be dereferenced to obtain an addend. shared libraries,
(including libc.so) and PIE executables were unaffected, since their
base addresses are the actual address of their mappings and are
readable. non-PIE main executables, however, have a base address of 0
because their load addresses are absolute and not offset at load time.

in practice none-type relocations do not arise with toolchains that
are in use except on mips, and on mips it's moderately rare for a
non-PIE executable to have a relocation table, since the mips-specific
got processing serves in its place for most purposes.
---

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index 42930adf..42b056d2 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -270,6 +270,7 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri
 	for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
 		if (skip_relative && IS_RELATIVE(rel[1])) continue;
 		type = R_TYPE(rel[1]);
+		if (type == REL_NONE) continue;
 		sym_index = R_SYM(rel[1]);
 		reloc_addr = (void *)(base + rel[0]);
 		if (sym_index) {