Re: [PATCH] Fix i386 memmove issue [BZ #22644]

[Andrew Senkevich <andrew dot n dot senkevich at gmail dot com>]

2018-03-19 18:57 GMT+01:00 H.J. Lu <hjl.tools@gmail.com>:
> On Mon, Mar 19, 2018 at 10:52 AM, Andrew Senkevich
> <andrew.n.senkevich@gmail.com> wrote:
>> 2018-03-19 16:33 GMT+01:00 Florian Weimer <fweimer@redhat.com>:
>>> On 03/19/2018 03:25 PM, Szabolcs Nagy wrote:
>>>>
>>>> i thought not using MAP_FIXED is the 'non-overriding MAP_FIXED variant'
>>
>> Hmm, I tried so and had got much bigger address. But now I see it
>> works (with size just 0x20000000 and 0x70000000 as a hint) in both 64
>> and 32 bit cases, so proposing the following:
>>
>> diff --git a/string/test-memmove.c b/string/test-memmove.c
>> index edc7a4c..fa4037d 100644
>> --- a/string/test-memmove.c
>> +++ b/string/test-memmove.c
>> @@ -24,6 +24,7 @@
>>  # define TEST_NAME "memmove"
>>  #endif
>>  #include "test-string.h"
>> +#include <support/test-driver.h>
>>
>>  char *simple_memmove (char *, const char *, size_t);
>>
>> @@ -245,6 +246,59 @@ do_random_tests (void)
>>      }
>>  }
>>
>> +static void
>> +do_test2 (void)
>> +{
>> +  size_t size = 0x20000000;
>> +  uint32_t * large_buf;
>> +
>> +  large_buf = mmap ((void*)0x70000000, size, PROT_READ | PROT_WRITE,
>> +     MAP_PRIVATE | MAP_ANON, -1, 0);
>> +
>> +  if (large_buf == MAP_FAILED)
>> +    error (EXIT_UNSUPPORTED, errno, "Large mmap failed");
>> +
>> +  if ((uintptr_t)large_buf > 0x80000000 - 128)
>
> Don't you need to test if address is too low such that
> 0x80000000 - (uintptr_t)large_buf > 0x20000000?

Indeed, thanks. Updated below.

diff --git a/string/test-memmove.c b/string/test-memmove.c
index edc7a4c..9f1437d 100644
--- a/string/test-memmove.c
+++ b/string/test-memmove.c
@@ -24,6 +24,7 @@
 # define TEST_NAME "memmove"
 #endif
 #include "test-string.h"
+#include <support/test-driver.h>

 char *simple_memmove (char *, const char *, size_t);

@@ -245,6 +246,60 @@ do_random_tests (void)
     }
 }

+static void
+do_test2 (void)
+{
+  size_t size = 0x20000000;
+  uint32_t * large_buf;
+
+  large_buf = mmap ((void*)0x70000000, size, PROT_READ | PROT_WRITE,
+     MAP_PRIVATE | MAP_ANON, -1, 0);
+
+  if (large_buf == MAP_FAILED)
+    error (EXIT_UNSUPPORTED, errno, "Large mmap failed");
+
+  if ((uintptr_t)large_buf > 0x80000000 - 128
+      || 0x80000000 - (uintptr_t)large_buf > 0x20000000)
+    {
+      error (0, 0,"Large mmap allocated improperly");
+      ret = EXIT_UNSUPPORTED;
+      munmap((void *)large_buf, size);
+      return;
+    }
+
+  size_t bytes_move = 0x80000000 - (uintptr_t)large_buf;
+  size_t arr_size = bytes_move / sizeof(uint32_t);
+  size_t i;
+
+  FOR_EACH_IMPL (impl, 0)
+    {
+      for (i = 0; i < arr_size; i++)
+        large_buf[i] = i;
+
+      uint32_t * dst = &large_buf[33];
+
+#ifdef TEST_BCOPY
+      CALL (impl, (char *)large_buf, (char *)dst, bytes_move);
+#else
+      CALL (impl, (char *)dst, (char *)large_buf, bytes_move);
+#endif
+
+      for (i = 0; i < arr_size; i++)
+        {
+          if (dst[i] != i)
+     {
+       error (0, 0,
+      "Wrong result in function %s dst \"%p\" src \"%p\" offset \"%d\"",
+      impl->name, dst, large_buf, i);
+       ret = 1;
+       break;
+     }
+ }
+    }
+
+  munmap((void *)large_buf, size);
+}
+
 int
 test_main (void)
 {
@@ -284,6 +339,9 @@ test_main (void)
     }

   do_random_tests ();
+
+  do_test2 ();
+
   return ret;
 }



--
WBR,
Andrew