@@ -467,12 +467,19 @@ extern unsigned long guest_stack_size;
#define VERIFY_READ 0
#define VERIFY_WRITE 1 /* implies read access */
-static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
+static inline bool access_ok(int type, abi_ulong addr, abi_ulong size)
{
- return guest_addr_valid(addr) &&
- (size == 0 || guest_addr_valid(addr + size - 1)) &&
- page_check_range((target_ulong)addr, size,
- (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
+ if (!guest_addr_valid(addr)) {
+ return false;
+ }
+ if (size != 0 &&
+ (addr + size - 1 < addr ||
+ !guest_addr_valid(addr + size - 1))) {
+ return false;
+ }
+ return page_check_range((target_ulong)addr, size,
+ (type == VERIFY_READ) ? PAGE_READ :
+ (PAGE_READ | PAGE_WRITE)) == 0;
}
/* NOTE __get_user and __put_user use host pointers and don't check access.
Verify that addr + size - 1 does not wrap around. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- linux-user/qemu.h | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)