track function symbols

grub-core/gensymlist.sh

@@ -47,7 +47,7 @@ grub_register_exported_symbols (void)
 EOF
 
 cat <<EOF
-  struct symtab { const char *name; void *addr; };
+  struct symtab { const char *name; void *addr; int isfunc; };
   struct symtab *p;
   static struct symtab tab[] =
     {
@@ -56,16 +56,16 @@ EOF
 (while read LINE; do echo $LINE; done) \
   | grep -v '^#' \
   | sed -n \
-        -e '/EXPORT_FUNC *([a-zA-Z0-9_]*)/{s/.*EXPORT_FUNC *(\([a-zA-Z0-9_]*\)).*/      {"\1", \1},/;p;}' \
-        -e '/EXPORT_VAR *([a-zA-Z0-9_]*)/{s/.*EXPORT_VAR *(\([a-zA-Z0-9_]*\)).*/      {"\1", \&\1},/;p;}' \
+        -e '/EXPORT_FUNC *([a-zA-Z0-9_]*)/{s/.*EXPORT_FUNC *(\([a-zA-Z0-9_]*\)).*/      {"\1", \1, 1},/;p;}' \
+        -e '/EXPORT_VAR *([a-zA-Z0-9_]*)/{s/.*EXPORT_VAR *(\([a-zA-Z0-9_]*\)).*/      {"\1", \&\1, 0},/;p;}' \
   | sort -u
 
 cat <<EOF
-      {0, 0}
+      {0, 0, 0}
     };
 
   COMPILE_TIME_ASSERT (sizeof (tab) > sizeof (tab[0]));
   for (p = tab; p->name; p++)
-    grub_dl_register_symbol (p->name, p->addr, 0);
+    grub_dl_register_symbol (p->name, p->addr, p->isfunc, 0);
 }
 EOF

grub-core/kern/dl.c

@@ -90,6 +90,7 @@ struct grub_symbol
   struct grub_symbol *next;
   const char *name;
   void *addr;
+  int isfunc;
   grub_dl_t mod;	/* The module to which this symbol belongs.  */
 };
 typedef struct grub_symbol *grub_symbol_t;
@@ -114,21 +115,22 @@ grub_symbol_hash (const char *s)
 
 /* Resolve the symbol name NAME and return the address.
    Return NULL, if not found.  */
-static void *
+static grub_symbol_t
 grub_dl_resolve_symbol (const char *name)
 {
   grub_symbol_t sym;
 
   for (sym = grub_symtab[grub_symbol_hash (name)]; sym; sym = sym->next)
     if (grub_strcmp (sym->name, name) == 0)
-      return sym->addr;
+      return sym;
 
   return 0;
 }
 
 /* Register a symbol with the name NAME and the address ADDR.  */
 grub_err_t
-grub_dl_register_symbol (const char *name, void *addr, grub_dl_t mod)
+grub_dl_register_symbol (const char *name, void *addr, int isfunc,
+			 grub_dl_t mod)
 {
   grub_symbol_t sym;
   unsigned k;
@@ -151,6 +153,7 @@ grub_dl_register_symbol (const char *name, void *addr, grub_dl_t mod)
 
   sym->addr = addr;
   sym->mod = mod;
+  sym->isfunc = isfunc;
 
   k = grub_symbol_hash (name);
   sym->next = grub_symtab[k];
@@ -371,17 +374,20 @@ grub_dl_resolve_symbols (grub_dl_t mod, Elf_Ehdr *e)
 	  /* Resolve a global symbol.  */
 	  if (sym->st_name != 0 && sym->st_shndx == 0)
 	    {
-	      sym->st_value = (Elf_Addr) grub_dl_resolve_symbol (name);
-	      if (! sym->st_value)
+	      grub_symbol_t nsym = grub_dl_resolve_symbol (name);
+	      if (! nsym)
 		return grub_error (GRUB_ERR_BAD_MODULE,
 				   "symbol not found: `%s'", name);
+	      sym->st_value = (Elf_Addr) nsym->addr;
+	      if (nsym->isfunc)
+		sym->st_info = ELF_ST_INFO (bind, STT_FUNC);
 	    }
 	  else
 	    {
 	      sym->st_value += (Elf_Addr) grub_dl_get_section_addr (mod,
 								    sym->st_shndx);
 	      if (bind != STB_LOCAL)
-		if (grub_dl_register_symbol (name, (void *) sym->st_value, mod))
+		if (grub_dl_register_symbol (name, (void *) sym->st_value, 0, mod))
 		  return grub_errno;
 	    }
 	  break;
@@ -398,13 +404,11 @@ grub_dl_resolve_symbols (grub_dl_t mod, Elf_Ehdr *e)
 		return grub_errno;
 	      desc[0] = (void *) sym->st_value;
 	      desc[1] = mod->base;
-	      if (grub_dl_register_symbol (name, (void *) desc, mod))
-		return grub_errno;
 	      sym->st_value = (grub_addr_t) desc;
 	  }
 #endif
 	  if (bind != STB_LOCAL)
-	    if (grub_dl_register_symbol (name, (void *) sym->st_value, mod))
+	    if (grub_dl_register_symbol (name, (void *) sym->st_value, 1, mod))
 	      return grub_errno;
 	  if (grub_strcmp (name, "grub_mod_init") == 0)
 	    mod->init = (void (*) (grub_dl_t)) sym->st_value;

include/grub/dl.h

@@ -116,7 +116,7 @@ extern grub_dl_t EXPORT_VAR(grub_dl_head);
 
 grub_dl_t EXPORT_FUNC(grub_dl_get) (const char *name);
 grub_err_t grub_dl_register_symbol (const char *name, void *addr,
-				    grub_dl_t mod);
+				    int isfunc, grub_dl_t mod);
 
 grub_err_t grub_arch_dl_check_header (void *ehdr);
 grub_err_t grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr);

include/grub/elf.h

@@ -2348,6 +2348,8 @@ typedef Elf32_Xword Elf_Xword;
 
 #define ELF_ST_BIND(val)	ELF32_ST_BIND(val)
 #define ELF_ST_TYPE(val)	ELF32_ST_TYPE(val)
+#define ELF_ST_INFO(a,b)	ELF32_ST_INFO(a,b)
+
 #define ELF_R_SYM(val)		ELF32_R_SYM(val)
 #define ELF_R_TYPE(val)		ELF32_R_TYPE(val)
 #define ELF_R_INFO(sym, type)	ELF32_R_INFO(sym, type)
@@ -2369,6 +2371,7 @@ typedef Elf64_Xword Elf_Xword;
 
 #define ELF_ST_BIND(val)	ELF64_ST_BIND (val)
 #define ELF_ST_TYPE(val)	ELF64_ST_TYPE (val)
+#define ELF_ST_INFO(a,b)	ELF64_ST_INFO(a,b)
 #define ELF_R_SYM(val)		ELF64_R_SYM(val)
 #define ELF_R_TYPE(val)		ELF64_R_TYPE(val)
 #define ELF_R_INFO(sym, type)	ELF64_R_INFO(sym, type)