[PATCH 3.16.y-ckt 005/142] powerpc: Fix dedotify for binutils >= 2.26

[Luis Henriques]

3.16.7-ckt26 -stable review patch.  If anyone has any objections, please let me 
know.

---8<------------------------------------------------------------

From: Andreas Schwab <sch...@linux-m68k.org>

commit f15838e9cac8f78f0cc506529bb9d3b9fa589c1f upstream.

Since binutils 2.26 BFD is doing suffix merging on STRTAB sections.  But
dedotify modifies the symbol names in place, which can also modify
unrelated symbols with a name that matches a suffix of a dotted name.  To
remove the leading dot of a symbol name we can just increment the pointer
into the STRTAB section instead.

Backport to all stables to avoid breakage when people update their
binutils - mpe.

Signed-off-by: Andreas Schwab <sch...@linux-m68k.org>
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriq...@canonical.com>
---
 arch/powerpc/kernel/module_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index ec4106224d89..1a24e1c47588 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -337,7 +337,7 @@ static void dedotify(Elf64_Sym *syms, unsigned int numsyms, 
char *strtab)
                if (syms[i].st_shndx == SHN_UNDEF) {
                        char *name = strtab + syms[i].st_name;
                        if (name[0] == '.')
-                               memmove(name, name+1, strlen(name));
+                               syms[i].st_name++;
                }
        }
 }