BINFMT: fill_elf_header cleanup - use straight memset first

This patch does simplify fill_elf_header function by setting
to zero the whole elf header first. So we fillup the fields
we really need only.

before:
   text    data     bss     dec     hex filename
  11735      80       0   11815    2e27 fs/binfmt_elf.o

after:
   text    data     bss     dec     hex filename
  11710      80       0   11790    2e0e fs/binfmt_elf.o

viola, 25 bytes of text is freed

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 6 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 9924581df6f6..6cb4efbae885 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1255,26 +1255,23 @@ static int writenote(struct memelfnote *men, struct file *file,
 static void fill_elf_header(struct elfhdr *elf, int segs,
                             u16 machine, u32 flags, u8 osabi)
 {
+        memset(elf, 0, sizeof(*elf));
+
         memcpy(elf->e_ident, ELFMAG, SELFMAG);
         elf->e_ident[EI_CLASS] = ELF_CLASS;
         elf->e_ident[EI_DATA] = ELF_DATA;
         elf->e_ident[EI_VERSION] = EV_CURRENT;
         elf->e_ident[EI_OSABI] = ELF_OSABI;
-        memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
 
         elf->e_type = ET_CORE;
         elf->e_machine = machine;
         elf->e_version = EV_CURRENT;
-        elf->e_entry = 0;
         elf->e_phoff = sizeof(struct elfhdr);
-        elf->e_shoff = 0;
         elf->e_flags = flags;
         elf->e_ehsize = sizeof(struct elfhdr);
         elf->e_phentsize = sizeof(struct elf_phdr);
         elf->e_phnum = segs;
-        elf->e_shentsize = 0;
-        elf->e_shnum = 0;
-        elf->e_shstrndx = 0;
+
         return;
 }