diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c
index 4dceeb1fc5e0f229305c983d39c8cf6497b5a409..cf058fecfceec989354ec17a3d681cae65315935 100644
--- a/arch/x86/vdso/vdso32-setup.c
+++ b/arch/x86/vdso/vdso32-setup.c
@@ -162,7 +162,7 @@ static __init void relocate_vdso(Elf32_Ehdr *ehdr)
 	Elf32_Shdr *shdr;
 	int i;
 
-	BUG_ON(memcmp(ehdr->e_ident, ELFMAG, 4) != 0 ||
+	BUG_ON(memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0 ||
 	       !elf_check_arch_ia32(ehdr) ||
 	       ehdr->e_type != ET_DYN);