From a142bac4dbdb7f6c3b72c0102a4dcc4b926c3d72 Mon Sep 17 00:00:00 2001
From: Packit Service <user-cont-team+packit-service@redhat.com>
Date: Feb 12 2021 08:43:04 +0000
Subject: Apply patch glibc-rh1614979.patch


patch_name: glibc-rh1614979.patch
present_in_specfile: true
location_in_specfile: 35

---

diff --git a/sysdeps/x86/dl-prop.h b/sysdeps/x86/dl-prop.h
index 26c3131..9ab890d 100644
--- a/sysdeps/x86/dl-prop.h
+++ b/sysdeps/x86/dl-prop.h
@@ -49,6 +49,10 @@ _dl_process_cet_property_note (struct link_map *l,
 			      const ElfW(Addr) align)
 {
 #if CET_ENABLED
+  /* Skip if we have seen a NT_GNU_PROPERTY_TYPE_0 note before.  */
+  if (l->l_cet != lc_unknown)
+    return;
+
   /* The NT_GNU_PROPERTY_TYPE_0 note must be aliged to 4 bytes in
      32-bit objects and to 8 bytes in 64-bit objects.  Skip notes
      with incorrect alignment.  */
@@ -57,6 +61,9 @@ _dl_process_cet_property_note (struct link_map *l,
 
   const ElfW(Addr) start = (ElfW(Addr)) note;
 
+  unsigned int feature_1 = 0;
+  unsigned int last_type = 0;
+
   while ((ElfW(Addr)) (note + 1) - start < size)
     {
       /* Find the NT_GNU_PROPERTY_TYPE_0 note.  */
@@ -64,10 +71,18 @@ _dl_process_cet_property_note (struct link_map *l,
 	  && note->n_type == NT_GNU_PROPERTY_TYPE_0
 	  && memcmp (note + 1, "GNU", 4) == 0)
 	{
+	  /* Stop if we see more than one GNU property note which may
+	     be generated by the older linker.  */
+	  if (l->l_cet != lc_unknown)
+	    return;
+
+	  /* Check CET status now.  */
+	  l->l_cet = lc_none;
+
 	  /* Check for invalid property.  */
 	  if (note->n_descsz < 8
 	      || (note->n_descsz % sizeof (ElfW(Addr))) != 0)
-	    break;
+	    return;
 
 	  /* Start and end of property array.  */
 	  unsigned char *ptr = (unsigned char *) (note + 1) + 4;
@@ -78,9 +93,15 @@ _dl_process_cet_property_note (struct link_map *l,
 	      unsigned int type = *(unsigned int *) ptr;
 	      unsigned int datasz = *(unsigned int *) (ptr + 4);
 
+	      /* Property type must be in ascending order.  */
+	      if (type < last_type)
+		return;
+
 	      ptr += 8;
 	      if ((ptr + datasz) > ptr_end)
-		break;
+		return;
+
+	      last_type = type;
 
 	      if (type == GNU_PROPERTY_X86_FEATURE_1_AND)
 		{
@@ -89,14 +110,18 @@ _dl_process_cet_property_note (struct link_map *l,
 		     we stop the search regardless if its size is correct
 		     or not.  There is no point to continue if this note
 		     is ill-formed.  */
-		  if (datasz == 4)
-		    {
-		      unsigned int feature_1 = *(unsigned int *) ptr;
-		      if ((feature_1 & GNU_PROPERTY_X86_FEATURE_1_IBT))
-			l->l_cet |= lc_ibt;
-		      if ((feature_1 & GNU_PROPERTY_X86_FEATURE_1_SHSTK))
-			l->l_cet |= lc_shstk;
-		    }
+		  if (datasz != 4)
+		    return;
+
+		  feature_1 = *(unsigned int *) ptr;
+
+		  /* Keep searching for the next GNU property note
+		     generated by the older linker.  */
+		  break;
+		}
+	      else if (type > GNU_PROPERTY_X86_FEATURE_1_AND)
+		{
+		  /* Stop since property type is in ascending order.  */
 		  return;
 		}
 
@@ -112,6 +137,12 @@ _dl_process_cet_property_note (struct link_map *l,
 	      + ELF_NOTE_NEXT_OFFSET (note->n_namesz, note->n_descsz,
 				      align));
     }
+
+  /* We get here only if there is one or no GNU property note.  */
+  if ((feature_1 & GNU_PROPERTY_X86_FEATURE_1_IBT))
+    l->l_cet |= lc_ibt;
+  if ((feature_1 & GNU_PROPERTY_X86_FEATURE_1_SHSTK))
+    l->l_cet |= lc_shstk;
 #endif
 }
 
diff --git a/sysdeps/x86/link_map.h b/sysdeps/x86/link_map.h
index ef1206a..9367ed0 100644
--- a/sysdeps/x86/link_map.h
+++ b/sysdeps/x86/link_map.h
@@ -19,8 +19,9 @@
 /* If this object is enabled with CET.  */
 enum
   {
-    lc_none = 0,			 /* Not enabled with CET.  */
-    lc_ibt = 1 << 0,			 /* Enabled with IBT.  */
-    lc_shstk = 1 << 1,			 /* Enabled with STSHK.  */
+    lc_unknown = 0,			 /* Unknown CET status.  */
+    lc_none = 1 << 0,			 /* Not enabled with CET.  */
+    lc_ibt = 1 << 1,			 /* Enabled with IBT.  */
+    lc_shstk = 1 << 2,			 /* Enabled with STSHK.  */
     lc_ibt_and_shstk = lc_ibt | lc_shstk /* Enabled with both.  */
-  } l_cet:2;
+  } l_cet:3;