strip: Fix check test for SHN_XINDEX symbol.

The check for whether a symbol used the extended section table was
wrong causing the run-strip-test-many.sh testcase to declare the
testfile was an illformed file.

Fixing this exposed a strict elfutils check for the '.shstrtab'
section having this exact name and a SHT_STRTAB type. This might
be a little too strict, but easily worked around by changing the
name of the "old" shstrtab section in the addsections program.

Signed-off-by: Mark Wielaard <[email protected]>

4 files changed, 39 insertions, 10 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 0ea106c5..0544fceb 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2019-01-24  Mark Wielaard  <[email protected]>
+
+	* strip.c (handle_elf): Fix check test for SHN_XINDEX symbol.
+
 2019-01-22  Mark Wielaard  <[email protected]>
 
 	* readelf.c (print_debug_line_section): Check we are not at end of
diff --git a/src/strip.c b/src/strip.c
index 15180737..a73009d9 100644
--- a/src/strip.c
+++ b/src/strip.c
@@ -1944,7 +1944,7 @@ handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
 		      INTERNAL_ERROR (fname);
 
 		    if (sym->st_shndx == SHN_UNDEF
-			|| (sym->st_shndx >= shnum
+			|| (sym->st_shndx >= SHN_LORESERVE
 			    && sym->st_shndx != SHN_XINDEX))
 		      {
 			/* This is no section index, leave it alone
diff --git a/tests/ChangeLog b/tests/ChangeLog
index 8c9e7807..2dd8026d 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,9 @@
+2019-01-24  Mark Wielaard  <[email protected]>
+
+	* addsections.c (add_sections): Change the name of the old shstrtab
+	section to ".old_shstrtab" and give the old shstrtab name to the
+	new shstrtab section.
+
 2019-01-09  Ulf Hermann <[email protected]>
 
 	* run-readelf-compressed.sh: Skip if USE_BZIP2 not found.
diff --git a/tests/addsections.c b/tests/addsections.c
index 391c5b47..cc8d0655 100644
--- a/tests/addsections.c
+++ b/tests/addsections.c
@@ -92,7 +92,7 @@ add_sections (const char *name, size_t nr, int use_mmap)
 
   /* We will add a new shstrtab section with two new names at the end.
      Just get the current shstrtab table and add two entries '.extra'
-     and '.new_shstrtab' at the end of the table, so all existing indexes
+     and '.old_shstrtab' at the end of the table, so all existing indexes
      are still valid.  */
   size_t shstrndx;
   if (elf_getshdrstrndx (elf, &shstrndx) < 0)
@@ -115,7 +115,7 @@ add_sections (const char *name, size_t nr, int use_mmap)
     }
   size_t new_shstrtab_size = (shstrtab_data->d_size
 			      + strlen (".extra") + 1
-			      + strlen (".new_shstrtab") + 1);
+			      + strlen (".old_shstrtab") + 1);
   void *new_shstrtab_buf = malloc (new_shstrtab_size);
   if (new_shstrtab_buf == NULL)
     {
@@ -124,9 +124,30 @@ add_sections (const char *name, size_t nr, int use_mmap)
     }
   memcpy (new_shstrtab_buf, shstrtab_data->d_buf, shstrtab_data->d_size);
   size_t extra_idx = shstrtab_data->d_size;
-  size_t new_shstrtab_idx = extra_idx + strlen (".extra") + 1;
+  size_t old_shstrtab_idx = extra_idx + strlen (".extra") + 1;
   strcpy (new_shstrtab_buf + extra_idx, ".extra");
-  strcpy (new_shstrtab_buf + new_shstrtab_idx, ".new_shstrtab");
+  strcpy (new_shstrtab_buf + old_shstrtab_idx, ".old_shstrtab");
+
+  /* Change the name of the old shstrtab section, because elflint
+     has a strict check on the name/type for .shstrtab.  */
+  GElf_Shdr shdr_mem;
+  GElf_Shdr *shdr = gelf_getshdr (shstrtab_scn, &shdr_mem);
+  if (shdr == NULL)
+    {
+      printf ("cannot get header for old shstrtab section: %s\n",
+              elf_errmsg (-1));
+      exit (1);
+    }
+
+  size_t shstrtab_idx = shdr->sh_name;
+  shdr->sh_name = old_shstrtab_idx;
+
+  if (gelf_update_shdr (shstrtab_scn, shdr) == 0)
+    {
+      printf ("cannot update old shstrtab section header: %s\n",
+	      elf_errmsg (-1));
+      exit (1);
+    }
 
   // Add lots of .extra sections...
   size_t cnt = 0;
@@ -153,8 +174,7 @@ add_sections (const char *name, size_t nr, int use_mmap)
       data->d_type = ELF_T_BYTE;
       data->d_align = 1;
 
-      GElf_Shdr shdr_mem;
-      GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
+      shdr = gelf_getshdr (scn, &shdr_mem);
       if (shdr == NULL)
 	{
 	  printf ("cannot get header for new section (%zd): %s\n", cnt,
@@ -201,8 +221,7 @@ add_sections (const char *name, size_t nr, int use_mmap)
   new_shstrtab_data->d_type = ELF_T_BYTE;
   new_shstrtab_data->d_align = 1;
 
-  GElf_Shdr shdr_mem;
-  GElf_Shdr *shdr = gelf_getshdr (new_shstrtab_scn, &shdr_mem);
+  shdr = gelf_getshdr (new_shstrtab_scn, &shdr_mem);
   if (shdr == NULL)
     {
       printf ("cannot get header for new shstrtab section: %s\n",
@@ -218,7 +237,7 @@ add_sections (const char *name, size_t nr, int use_mmap)
   shdr->sh_addralign = 1;
   shdr->sh_entsize = 0;
   shdr->sh_size = new_shstrtab_size;
-  shdr->sh_name = new_shstrtab_idx;
+  shdr->sh_name = shstrtab_idx;
 
   // Finished new shstrtab section, update the header.
   if (gelf_update_shdr (new_shstrtab_scn, shdr) == 0)