commit 95059f9c313a7fbd7f22e4cdc1977c0393addc7b
author Richard Henderson <richard.henderson@linaro.org> Mon Mar 06 01:26:29 2023 +0300
committer Richard Henderson <richard.henderson@linaro.org> Tue Mar 28 15:23:10 2023 -0700
tree 5cbda761db3d946f2dafca04afaab139077596dd
parent a3a67f54f0b4ec98ff2380a792e5bfeebc47d554

include/exec: Change reserved_va semantics to last byte

Change the semantics to be the last byte of the guest va, rather
than the following byte.  This avoids some overflow conditions.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

bsd-user/main.c

diff --git a/bsd-user/main.c b/bsd-user/main.c
index 89f225d..babc3b0 100644
--- a/bsd-user/main.c
+++ b/bsd-user/main.c
@@ -68,13 +68,9 @@
 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
-/*
- * There are a number of places where we assign reserved_va to a variable
- * of type abi_ulong and expect it to fit.  Avoid the last page.
- */
-#   define MAX_RESERVED_VA  (0xfffffffful & TARGET_PAGE_MASK)
+#   define MAX_RESERVED_VA  0xfffffffful
 #  else
-#   define MAX_RESERVED_VA  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
+#   define MAX_RESERVED_VA  ((1ul << TARGET_VIRT_ADDR_SPACE_BITS) - 1)
 #  endif
 # else
 #  define MAX_RESERVED_VA  0
@@ -466,7 +462,7 @@
     envlist_free(envlist);
 
     if (reserved_va) {
-            mmap_next_start = reserved_va;
+        mmap_next_start = reserved_va + 1;
     }
 
     {