Make sure that all memory accesses are guarded.

This doesn't protect the fpreg reads completely. It's still possible to have
a bad address that has the first part in readable memory and the second part
in unreadable memory. Since none of the code android uses uses the fpreg
data, this should be okay.

Bug: 13946101

Change-Id: I9187b16d0427cbc8af6751cf0b8476ea2d1bfc38

5 files changed, 104 insertions, 40 deletions

diff --git a/include/tdep-aarch64/libunwind_i.h b/include/tdep-aarch64/libunwind_i.h
index 92541596..36250e3f 100644
--- a/include/tdep-aarch64/libunwind_i.h
+++ b/include/tdep-aarch64/libunwind_i.h
@@ -109,37 +109,49 @@ struct cursor
 static inline int
 dwarf_getfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t *val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_readable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *val = *(unw_fpreg_t *) DWARF_GET_LOC (loc);
+
+  *val = *addr;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_putfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_writable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *(unw_fpreg_t *) DWARF_GET_LOC (loc) = val;
+
+  *addr = val;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_get (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t *val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *val = *(unw_word_t *) DWARF_GET_LOC (loc);
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), val,
+				   0, c->as_arg);
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *(unw_word_t *) DWARF_GET_LOC (loc) = val;
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), &val,
+				   1, c->as_arg);
+/* End of ANDROID update. */
 }
 
 #else /* !UNW_LOCAL_ONLY */
diff --git a/include/tdep-arm/libunwind_i.h b/include/tdep-arm/libunwind_i.h
index 4577fb8c..1fed4bc5 100644
--- a/include/tdep-arm/libunwind_i.h
+++ b/include/tdep-arm/libunwind_i.h
@@ -97,37 +97,49 @@ struct cursor
 static inline int
 dwarf_getfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t *val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_readable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *val = *(unw_fpreg_t *) DWARF_GET_LOC (loc);
+
+  *val = *addr;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_putfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_writable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *(unw_fpreg_t *) DWARF_GET_LOC (loc) = val;
+
+  *addr = val;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_get (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t *val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *val = *(unw_word_t *) DWARF_GET_LOC (loc);
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), val,
+				   0, c->as_arg);
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *(unw_word_t *) DWARF_GET_LOC (loc) = val;
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), &val,
+				   1, c->as_arg);
+/* End of ANDROID update. */
 }
 
 #else /* !UNW_LOCAL_ONLY */
diff --git a/include/tdep-hppa/libunwind_i.h b/include/tdep-hppa/libunwind_i.h
index 1a595ad2..e8bb4f2b 100644
--- a/include/tdep-hppa/libunwind_i.h
+++ b/include/tdep-hppa/libunwind_i.h
@@ -94,37 +94,49 @@ struct cursor
 static inline int
 dwarf_getfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t *val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_readable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *val = *(unw_fpreg_t *) DWARF_GET_LOC (loc);
+
+  *val = *addr;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_putfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_writable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *(unw_fpreg_t *) DWARF_GET_LOC (loc) = val;
+
+  *addr = val;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_get (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t *val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *val = *(unw_word_t *) DWARF_GET_LOC (loc);
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), val,
+				   0, c->as_arg);
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *(unw_word_t *) DWARF_GET_LOC (loc) = val;
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), &val,
+				   1, c->as_arg);
+/* End of ANDROID update. */
 }
 
 #else /* !UNW_LOCAL_ONLY */
diff --git a/include/tdep-mips/libunwind_i.h b/include/tdep-mips/libunwind_i.h
index 9dae5557..0c532260 100644
--- a/include/tdep-mips/libunwind_i.h
+++ b/include/tdep-mips/libunwind_i.h
@@ -104,37 +104,53 @@ typedef long mips_reg_t;
 static inline int
 dwarf_getfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t *val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_readable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *val = *(unw_fpreg_t *) (intptr_t) DWARF_GET_LOC (loc);
+
+  *val = *addr;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_putfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_writable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *(unw_fpreg_t *) (intptr_t) DWARF_GET_LOC (loc) = val;
+
+  *addr = val;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_get (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t *val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  mips_reg_t *addr = (mips_reg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_readable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *val = *(mips_reg_t *) (intptr_t) DWARF_GET_LOC (loc);
+
+  *val = *addr;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  mips_reg_t *addr = (mips_reg_t *) (uintptr_t) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_writable ((unw_word_t) (uintptr_t) addr))
     return -1;
-  *(mips_reg_t *) (intptr_t) DWARF_GET_LOC (loc) = val;
+
+  *addr = val;
   return 0;
+/* End of ANDROID update. */
 }
 
 #else /* !UNW_LOCAL_ONLY */
diff --git a/include/tdep-sh/libunwind_i.h b/include/tdep-sh/libunwind_i.h
index dd361bfd..29b162b4 100644
--- a/include/tdep-sh/libunwind_i.h
+++ b/include/tdep-sh/libunwind_i.h
@@ -95,37 +95,49 @@ struct cursor
 static inline int
 dwarf_getfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t *val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_readable ((unw_word_t) addr))
     return -1;
-  *val = *(unw_fpreg_t *) DWARF_GET_LOC (loc);
+
+  *val = *addr;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_putfp (struct dwarf_cursor *c, dwarf_loc_t loc, unw_fpreg_t val)
 {
-  if (!DWARF_GET_LOC (loc))
+/* ANDROID support update. */
+  unw_fpreg_t *addr = (unw_fpreg_t *) DWARF_GET_LOC (loc);
+  if (!addr || !map_local_is_writable ((unw_word_t) addr))
     return -1;
-  *(unw_fpreg_t *) DWARF_GET_LOC (loc) = val;
+
+  *addr = val;
   return 0;
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_get (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t *val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *val = *(unw_word_t *) DWARF_GET_LOC (loc);
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), val,
+				   0, c->as_arg);
+/* End of ANDROID update. */
 }
 
 static inline int
 dwarf_put (struct dwarf_cursor *c, dwarf_loc_t loc, unw_word_t val)
 {
+/* ANDROID support update. */
   if (!DWARF_GET_LOC (loc))
     return -1;
-  *(unw_word_t *) DWARF_GET_LOC (loc) = val;
-  return 0;
+  return (*c->as->acc.access_mem) (c->as, DWARF_GET_LOC (loc), &val,
+				   1, c->as_arg);
+/* End of ANDROID update. */
 }
 
 #else /* !UNW_LOCAL_ONLY */