From: Alan Modra <amodra@gmail.com>
Date: Sun, 8 Nov 2015 17:29:00 +0000 (-0800)
Subject: ELF unexec: Symbol table patching
X-Git-Tag: emacs-25.0.90~877
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=190b968f189cb7d06223bb39045ec9055df67f68;p=emacs.git

ELF unexec: Symbol table patching

No st_shndx value larger than SHN_LORESERVE should be changed.
* unexelf.c (unexec): Don't adjust any st_shndx larger than
SHN_LORESERVE.  Error on SHN_XINDEX.
---

diff --git a/src/unexelf.c b/src/unexelf.c
index 0065491b453..286ba2e99c1 100644
--- a/src/unexelf.c
+++ b/src/unexelf.c
@@ -1118,7 +1118,7 @@ temacs:
 	}
 #endif /* __sgi */
 
-      /* If it is the symbol table, its st_shndx field needs to be patched.  */
+      /* Patch st_shndx field of symbol table.  */
       if (new_shdr->sh_type == SHT_SYMTAB
 	  || new_shdr->sh_type == SHT_DYNSYM)
 	{
@@ -1126,9 +1126,10 @@ temacs:
 	  ElfW (Sym) *sym = (ElfW (Sym) *) (new_shdr->sh_offset + new_base);
 	  for (; num--; sym++)
 	    {
-	      if ((sym->st_shndx == SHN_UNDEF)
-		  || (sym->st_shndx == SHN_ABS)
-		  || (sym->st_shndx == SHN_COMMON))
+	      if (sym->st_shndx == SHN_XINDEX)
+		fatal ("SHT_SYMTAB_SHNDX unsupported");
+	      if (sym->st_shndx == SHN_UNDEF
+		  || sym->st_shndx >= SHN_LORESERVE)
 		continue;
 
 	      PATCH_INDEX (sym->st_shndx);