[PATCH 4.2.y-ckt 126/273] powerpc: Fix dedotify for binutils >= 2.26

[Kamal Mostafa]

4.2.8-ckt5 -stable review patch.  If anyone has any objections, please let me know.

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

From: Andreas Schwab <schwab@xxxxxxxxxxxxxx>

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 <schwab@xxxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 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 59663af..e4f7d4e 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -335,7 +335,7 @@ 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++;
 		}
 	}
 }
-- 
2.7.0