Blob Blame Raw
--- binutils.orig/binutils/readelf.c	2018-05-31 10:14:28.019641872 +0100
+++ binutils-2.29/binutils/readelf.c	2018-05-31 10:57:28.912460915 +0100
@@ -10154,9 +10154,8 @@ process_version_sections (FILE * file)
 	case SHT_GNU_verdef:
 	  {
 	    Elf_External_Verdef * edefs;
-	    unsigned int idx;
-	    unsigned int cnt;
-	    unsigned int end;
+	    unsigned long idx;
+	    unsigned long cnt;
 	    char * endbuf;
 
 	    found = TRUE;
@@ -10178,23 +10177,16 @@ process_version_sections (FILE * file)
 	      break;
 	    endbuf = (char *) edefs + section->sh_size;
 
-	    /* PR 17531: file: id:000001,src:000172+005151,op:splice,rep:2.  */
-	    end = (section->sh_info < section->sh_size
-		   ? section->sh_info : section->sh_size);
-	    for (idx = cnt = 0; cnt < end; ++cnt)
+	    for (idx = cnt = 0; cnt < section->sh_info; ++cnt)
 	      {
 		char * vstart;
 		Elf_External_Verdef * edef;
 		Elf_Internal_Verdef ent;
 		Elf_External_Verdaux * eaux;
 		Elf_Internal_Verdaux aux;
-		unsigned int isum;
+		unsigned long isum;
 		int j;
 
-		/* Check for very large indices.  */
-		if (idx > (size_t) (endbuf - (char *) edefs))
-		  break;
-
 		vstart = ((char *) edefs) + idx;
 		if (vstart + sizeof (*edef) > endbuf)
 		  break;
@@ -10209,19 +10201,20 @@ process_version_sections (FILE * file)
 		ent.vd_aux     = BYTE_GET (edef->vd_aux);
 		ent.vd_next    = BYTE_GET (edef->vd_next);
 
-		printf (_("  %#06x: Rev: %d  Flags: %s"),
+		printf (_("  %#06lx: Rev: %d  Flags: %s"),
 			idx, ent.vd_version, get_ver_flags (ent.vd_flags));
 
 		printf (_("  Index: %d  Cnt: %d  "),
 			ent.vd_ndx, ent.vd_cnt);
 
-		/* Check for overflow and underflow.  */
-		if (ent.vd_aux + sizeof (* eaux) > (size_t) (endbuf - vstart)
-		    || (vstart + ent.vd_aux < vstart))
+		/* Check for overflow.  */
+		if (ent.vd_aux > (size_t) (endbuf - vstart))
 		  break;
 
 		vstart += ent.vd_aux;
 
+		if (vstart + sizeof (*eaux) > endbuf)
+		  break;
 		eaux = (Elf_External_Verdaux *) vstart;
 
 		aux.vda_name = BYTE_GET (eaux->vda_name);
@@ -10236,6 +10229,14 @@ process_version_sections (FILE * file)
 
 		for (j = 1; j < ent.vd_cnt; j++)
 		  {
+		    if (aux.vda_next < sizeof (*eaux)
+			&& !(j == ent.vd_cnt - 1 && aux.vda_next == 0))
+		      {
+			warn (_("Invalid vda_next field of %lx\n"),
+			      aux.vda_next);
+			j = ent.vd_cnt;
+			break;
+		      }
 		    /* Check for overflow.  */
 		    if (aux.vda_next > (size_t) (endbuf - vstart))
 		      break;
@@ -10243,18 +10244,18 @@ process_version_sections (FILE * file)
 		    isum   += aux.vda_next;
 		    vstart += aux.vda_next;
 
-		    eaux = (Elf_External_Verdaux *) vstart;
 		    if (vstart + sizeof (*eaux) > endbuf)
 		      break;
+		    eaux = (Elf_External_Verdaux *) vstart;
 
 		    aux.vda_name = BYTE_GET (eaux->vda_name);
 		    aux.vda_next = BYTE_GET (eaux->vda_next);
 
 		    if (VALID_DYNAMIC_NAME (aux.vda_name))
-		      printf (_("  %#06x: Parent %d: %s\n"),
+		      printf (_("  %#06lx: Parent %d: %s\n"),
 			      isum, j, GET_DYNAMIC_NAME (aux.vda_name));
 		    else
-		      printf (_("  %#06x: Parent %d, name index: %ld\n"),
+		      printf (_("  %#06lx: Parent %d, name index: %ld\n"),
 			      isum, j, aux.vda_name);
 		  }
 
@@ -10263,7 +10264,14 @@ process_version_sections (FILE * file)
 
 		/* PR 17531:
 		   file: id:000001,src:000172+005151,op:splice,rep:2.  */
-		if (idx + ent.vd_next < idx)
+		if (ent.vd_next < sizeof (*edef)
+		    && !(cnt == section->sh_info - 1 && ent.vd_next == 0))
+		  {
+		    warn (_("Invalid vd_next field of %lx\n"), ent.vd_next);
+		    cnt = section->sh_info;
+		    break;
+		  }
+		if (ent.vd_next > (size_t) (endbuf - ((char *) edefs + idx)))
 		  break;
 
 		idx += ent.vd_next;
@@ -10279,8 +10287,8 @@ process_version_sections (FILE * file)
 	case SHT_GNU_verneed:
 	  {
 	    Elf_External_Verneed * eneed;
-	    unsigned int idx;
-	    unsigned int cnt;
+	    unsigned long idx;
+	    unsigned long cnt;
 	    char * endbuf;
 
 	    found = TRUE;
@@ -10306,13 +10314,10 @@ process_version_sections (FILE * file)
 	      {
 		Elf_External_Verneed * entry;
 		Elf_Internal_Verneed ent;
-		unsigned int isum;
+		unsigned long isum;
 		int j;
 		char * vstart;
 
-		if (idx > (size_t) (endbuf - (char *) eneed))
-		  break;
-
 		vstart = ((char *) eneed) + idx;
 		if (vstart + sizeof (*entry) > endbuf)
 		  break;
@@ -10325,7 +10330,7 @@ process_version_sections (FILE * file)
 		ent.vn_aux     = BYTE_GET (entry->vn_aux);
 		ent.vn_next    = BYTE_GET (entry->vn_next);
 
-		printf (_("  %#06x: Version: %d"), idx, ent.vn_version);
+		printf (_("  %#06lx: Version: %d"), idx, ent.vn_version);
 
 		if (VALID_DYNAMIC_NAME (ent.vn_file))
 		  printf (_("  File: %s"), GET_DYNAMIC_NAME (ent.vn_file));
@@ -10355,24 +10360,26 @@ process_version_sections (FILE * file)
 		    aux.vna_next  = BYTE_GET (eaux->vna_next);
 
 		    if (VALID_DYNAMIC_NAME (aux.vna_name))
-		      printf (_("  %#06x:   Name: %s"),
+		      printf (_("  %#06lx:   Name: %s"),
 			      isum, GET_DYNAMIC_NAME (aux.vna_name));
 		    else
-		      printf (_("  %#06x:   Name index: %lx"),
+		      printf (_("  %#06lx:   Name index: %lx"),
 			      isum, aux.vna_name);
 
 		    printf (_("  Flags: %s  Version: %d\n"),
 			    get_ver_flags (aux.vna_flags), aux.vna_other);
 
-		    /* Check for overflow.  */
-		    if (aux.vna_next > (size_t) (endbuf - vstart)
-			|| (aux.vna_next == 0 && j < ent.vn_cnt - 1))
+		    if (aux.vna_next < sizeof (*eaux)
+			&& !(j == ent.vn_cnt - 1 && aux.vna_next == 0))
 		      {
 			warn (_("Invalid vna_next field of %lx\n"),
 			      aux.vna_next);
 			j = ent.vn_cnt;
 			break;
 		      }
+		    /* Check for overflow.  */
+		    if (aux.vna_next > (size_t) (endbuf - vstart))
+		      break;
 		    isum   += aux.vna_next;
 		    vstart += aux.vna_next;
 		  }
@@ -10380,12 +10387,15 @@ process_version_sections (FILE * file)
 		if (j < ent.vn_cnt)
 		  warn (_("Missing Version Needs auxillary information\n"));
 
-		if (ent.vn_next == 0 && cnt < section->sh_info - 1)
+		if (ent.vn_next < sizeof (*entry)
+		    && !(cnt == section->sh_info - 1 && ent.vn_next == 0))
 		  {
-		    warn (_("Corrupt Version Needs structure - offset to next structure is zero with entries still left to be processed\n"));
+		    warn (_("Invalid vn_next field of %lx\n"), ent.vn_next);
 		    cnt = section->sh_info;
 		    break;
 		  }
+		if (ent.vn_next > (size_t) (endbuf - ((char *) eneed + idx)))
+		  break;
 		idx += ent.vn_next;
 	      }
 
@@ -12859,7 +12869,9 @@ dump_section_as_strings (Elf_Internal_Sh
   real_start = start = (unsigned char *) get_section_contents (section,
 							       file);
   if (start == NULL)
-    return FALSE;
+    /* PR 21820: Do not fail if the section was empty.  */
+    return (section->sh_size == 0 || section->sh_type == SHT_NOBITS) ? TRUE : FALSE;
+
   num_bytes = section->sh_size;
 
   printf (_("\nString dump of section '%s':\n"), printable_section_name (section));
@@ -13005,7 +13017,8 @@ dump_section_as_bytes (Elf_Internal_Shdr
 
   real_start = start = (unsigned char *) get_section_contents (section, file);
   if (start == NULL)
-    return FALSE;
+    /* PR 21820: Do not fail if the section was empty.  */
+    return (section->sh_size == 0 || section->sh_type == SHT_NOBITS) ? TRUE : FALSE;
 
   section_size = section->sh_size;