File 0001-Accept-read-only-PT_LOAD-segments-and-.rod... of Package valgrind.9221

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File 0001-Accept-read-only-PT_LOAD-segments-and-.rodata.patch of Package valgrind.9221

From cb72566ac3af13889f7ae88068c3b3ee6a6b757b Mon Sep 17 00:00:00 2001
From: Mark Wielaard <mark@klomp.org>
Date: Thu, 12 Jul 2018 13:56:00 +0200
Subject: [PATCH] Accept read-only PT_LOAD segments and .rodata.

The new binutils ld -z separate-code option creates multiple read-only
PT_LOAD segments and might place .rodata in a non-executable segment.

Allow and keep track of separate read-only segments and allow a readonly
page with .rodata section.

Based on patches from Tom Hughes <tom@compton.nu> and
H.J. Lu <hjl.tools@gmail.com>.

https://bugs.kde.org/show_bug.cgi?id=395682

[sbruens] Backported to 3.13.0 release
---
 coregrind/m_debuginfo/debuginfo.c |  2 --
 coregrind/m_debuginfo/readelf.c   | 34 +++++++++++++++++++++++--------
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/coregrind/m_debuginfo/debuginfo.c b/coregrind/m_debuginfo/debuginfo.c
index 24814d8..2cf433a 100644
--- a/coregrind/m_debuginfo/debuginfo.c
+++ b/coregrind/m_debuginfo/debuginfo.c
@@ -957,9 +957,7 @@ ULong VG_(di_notify_mmap)( Addr a, Bool allow_SkFileV, Int use_fd )
 #    error "Unknown platform"
 #  endif
 
-#  if defined(VGP_x86_darwin) && DARWIN_VERS >= DARWIN_10_7
    is_ro_map = seg->hasR && !seg->hasW && !seg->hasX;
-#  endif
 
 #  if defined(VGO_solaris)
    is_rx_map = seg->hasR && seg->hasX && !seg->hasW;
diff --git a/coregrind/m_debuginfo/readelf.c b/coregrind/m_debuginfo/readelf.c
index 3c8e62b..34a40c9 100644
--- a/coregrind/m_debuginfo/readelf.c
+++ b/coregrind/m_debuginfo/readelf.c
@@ -1785,7 +1785,7 @@ Bool ML_(read_elf_debug_info) ( struct _DebugInfo* di )
                Bool loaded = False;
                for (j = 0; j < VG_(sizeXA)(di->fsm.maps); j++) {
                   const DebugInfoMapping* map = VG_(indexXA)(di->fsm.maps, j);
-                  if (   (map->rx || map->rw)
+                  if (   (map->rx || map->rw || map->ro)
                       && map->size > 0 /* stay sane */
                       && a_phdr.p_offset >= map->foff
                       && a_phdr.p_offset <  map->foff + map->size
@@ -1816,6 +1816,16 @@ Bool ML_(read_elf_debug_info) ( struct _DebugInfo* di )
                            i, (UWord)item.bias);
                         loaded = True;
                      }
+                     if (map->ro
+                         && (a_phdr.p_flags & (PF_R | PF_W | PF_X))
+                            == PF_R) {
+                        item.exec = False;
+                        VG_(addToXA)(svma_ranges, &item);
+                        TRACE_SYMTAB(
+                           "PT_LOAD[%ld]:   acquired as ro, bias 0x%lx\n",
+                           i, (UWord)item.bias);
+                        loaded = True;
+                     }
                   }
                }
                if (!loaded) {
@@ -2083,17 +2093,25 @@ Bool ML_(read_elf_debug_info) ( struct _DebugInfo* di )
          }
       }
 
-      /* Accept .rodata where mapped as rx (data), even if zero-sized */
+      /* Accept .rodata where mapped as rx or rw (data), even if zero-sized */
       if (0 == VG_(strcmp)(name, ".rodata")) {
-         if (inrx && !di->rodata_present) {
-            di->rodata_present = True;
+         if (!di->rodata_present) {
             di->rodata_svma = svma;
-            di->rodata_avma = svma + inrx->bias;
+            di->rodata_avma = svma;
             di->rodata_size = size;
-            di->rodata_bias = inrx->bias;
             di->rodata_debug_svma = svma;
-            di->rodata_debug_bias = inrx->bias;
-                                    /* NB was 'inrw' prior to r11794 */
+            if (inrx) {
+               di->rodata_avma += inrx->bias;
+               di->rodata_bias = inrx->bias;
+               di->rodata_debug_bias = inrx->bias;
+            } else if (inrw) {
+               di->rodata_avma += inrw->bias;
+               di->rodata_bias = inrw->bias;
+               di->rodata_debug_bias = inrw->bias;
+            } else {
+               BAD(".rodata");
+            }
+            di->rodata_present = True;
             TRACE_SYMTAB("acquiring .rodata svma = %#lx .. %#lx\n",
                          di->rodata_svma,
                          di->rodata_svma + di->rodata_size - 1);
-- 
2.18.0

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File 0001-Accept-read-only-PT_LOAD-segments-and-.rodata.patch of Package valgrind.9221

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