libelf: section index 0 is special

When iterating over sections, table entry zero needs to be ignored.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/common/libelf/libelf-dominfo.c
+++ b/xen/common/libelf/libelf-dominfo.c
@@ -536,7 +536,7 @@ elf_errorstatus elf_xen_parse(struct elf
     if ( xen_elfnotes == 0 )
     {
         count = elf_shdr_count(elf);
-        for ( i = 0; i < count; i++ )
+        for ( i = 1; i < count; i++ )
         {
             shdr = elf_shdr_by_index(elf, i);
             if ( !elf_access_ok(elf, ELF_HANDLE_PTRVAL(shdr), 1) )
--- a/xen/common/libelf/libelf-loader.c
+++ b/xen/common/libelf/libelf-loader.c
@@ -79,7 +79,7 @@ elf_errorstatus elf_init(struct elf_bina
 
     /* Find symbol table and symbol string table. */
     count = elf_shdr_count(elf);
-    for ( i = 0; i < count; i++ )
+    for ( i = 1; i < count; i++ )
     {
         shdr = elf_shdr_by_index(elf, i);
         if ( !elf_access_ok(elf, ELF_HANDLE_PTRVAL(shdr), 1) )
--- a/xen/common/libelf/libelf-tools.c
+++ b/xen/common/libelf/libelf-tools.c
@@ -153,7 +153,7 @@ ELF_HANDLE_DECL(elf_shdr) elf_shdr_by_na
     const char *sname;
     unsigned i;
 
-    for ( i = 0; i < count; i++ )
+    for ( i = 1; i < count; i++ )
     {
         shdr = elf_shdr_by_index(elf, i);
         if ( !elf_access_ok(elf, ELF_HANDLE_PTRVAL(shdr), 1) )