(elf_machine_rel): Correct handling of PC24 relocs with negative value.

diff --git a/sysdeps/arm/dl-machine.h b/sysdeps/arm/dl-machine.h
index 9b40e6f..36ae4cf 100644 (file)
--- a/sysdeps/arm/dl-machine.h
+++ b/sysdeps/arm/dl-machine.h
@@ -478,17 +478,25 @@ elf_machine_rel (struct link_map *map, const Elf32_Rel *reloc,
        case R_ARM_PC24:
          {
             Elf32_Sword addend;
-            Elf32_Addr newvalue;
+            Elf32_Addr newvalue, topbits;
 
             addend = *reloc_addr & 0x00ffffff;
             if (addend & 0x00800000) addend |= 0xff000000;
 
             newvalue = value - (Elf32_Addr)reloc_addr + (addend << 2);
-            if (newvalue & 0xfc000003)
-              newvalue = fix_bad_pc24(reloc_addr, value)
-                - (Elf32_Addr)reloc_addr + (addend << 2);
-
-            newvalue = newvalue >> 2;
+            topbits = newvalue & 0xfe000000;
+            if (topbits != 0xfe000000 && topbits != 0x00000000)
+              {
+                newvalue = fix_bad_pc24(reloc_addr, value)
+                  - (Elf32_Addr)reloc_addr + (addend << 2);
+                topbits = newvalue & 0xfe000000;
+                if (topbits != 0xfe000000 && topbits != 0x00000000)
+                  {
+                    _dl_signal_error (0, map->l_name,
+                                      "R_ARM_PC24 relocation out of range");
+                  }
+              }
+            newvalue >>= 2;
             value = (*reloc_addr & 0xff000000) | (newvalue & 0x00ffffff);
             *reloc_addr = value;
          }