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Re: [PATCH] Fix i386 memmove issue [BZ #22644]
- From: Andrew Senkevich <andrew dot n dot senkevich at gmail dot com>
- To: Andreas Schwab <schwab at suse dot de>
- Cc: libc-alpha <libc-alpha at sourceware dot org>, Max Horn <max at quendi dot de>
- Date: Wed, 14 Mar 2018 15:43:14 +0100
- Subject: Re: [PATCH] Fix i386 memmove issue [BZ #22644]
- References: <CAMXFM3s5b2a6o_CMS0cJ35oE3SuJUHssqLAUY94LSZhEEtG71A@mail.gmail.com> <mvm606ts2w6.fsf@suse.de>
2018-02-19 11:13 GMT+01:00 Andreas Schwab <schwab@suse.de>:
> On Feb 19 2018, Andrew Senkevich <andrew.n.senkevich@gmail.com> wrote:
>
>> diff --git a/string/test-memmove.c b/string/test-memmove.c
>> index edc7a4c..8dc152b
>> --- a/string/test-memmove.c
>> +++ b/string/test-memmove.c
>> @@ -245,6 +245,49 @@ do_random_tests (void)
>> }
>> }
>>
>> +#if __SIZEOF_POINTER__ == 4
>> +static void
>> +do_test2 (void)
>> +{
>> + uint32_t i;
>> + uint32_t num = 0x20000000;
>> + uint32_t * large_buf = mmap (0, sizeof(uint32_t) * num, PROT_READ |
>> PROT_WRITE,
>> + MAP_PRIVATE | MAP_ANON, -1, 0);
>> + if (large_buf == MAP_FAILED)
>> + error (EXIT_FAILURE, errno, "large mmap failed");
>> +
>> + if (!((uint32_t)(large_buf) < (0x80000000 - 128) && (0x80000000 +
>> 128) < (uint32_t)(&large_buf[num])))
>> + {
>> + error (0, 0,"allocated large memory doesn't cross 0x80000000 boundary");
>> + ret = 1;
>> + return;
>
> Please properly fold long lines, and remove the redundant parens. Also,
> there is no guarantee that the address range is unallocated.
Thanks, updated patch below. Any comment or it is Ok for trunk?
diff --git a/string/test-memmove.c b/string/test-memmove.c
index edc7a4c..a8c4af4 100644
--- a/string/test-memmove.c
+++ b/string/test-memmove.c
@@ -245,6 +245,57 @@ do_random_tests (void)
}
}
+#if __SIZEOF_POINTER__ == 4
+static void
+do_test2 (void)
+{
+ uint32_t i;
+ uint32_t num = 0x20000000;
+ uint32_t * large_buf = mmap (0, sizeof(uint32_t) * num,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON, -1, 0);
+ if (large_buf == MAP_FAILED)
+ error (EXIT_FAILURE, errno, "Large mmap failed");
+
+ if ((uint32_t)large_buf > 0x80000000 - 128
+ || (uint32_t)&large_buf[num] < 0x80000000 + 128)
+ {
+ error (0, 0,"Large mmap doesn't cross 0x80000000 boundary");
+ ret = EXIT_UNSUPPORTED;
+ munmap((void *)large_buf, sizeof(uint32_t) * num);
+ return;
+ }
+
+ int bytes_move = 0x80000000 - (uint32_t)large_buf;
+ int arr_size = bytes_move / sizeof(uint32_t);
+
+ FOR_EACH_IMPL (impl, 0)
+ {
+ for (i = 0; i < arr_size; i++)
+ large_buf[i] = i;
+
+ uint32_t * dst = &large_buf[33];
+
+ CALL (impl, (char *)dst, (char *)large_buf, bytes_move);
+
+ 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;
+ munmap((void *)large_buf, sizeof(uint32_t) * num);
+ return;
+ }
+ }
+ }
+
+ munmap((void *)large_buf, sizeof(uint32_t) * num);
+}
+#endif
+
int
test_main (void)
{
@@ -284,6 +335,11 @@ test_main (void)
}
do_random_tests ();
+
+#if __SIZEOF_POINTER__ == 4
+ do_test2 ();
+#endif
+
return ret;
}
diff --git a/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
b/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
index 9c3bbe7..9aa17de 100644
--- a/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
+++ b/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
@@ -72,7 +72,7 @@ ENTRY (MEMCPY)
cmp %edx, %eax
# ifdef USE_AS_MEMMOVE
- jg L(check_forward)
+ ja L(check_forward)
L(mm_len_0_or_more_backward):
/* Now do checks for lengths. We do [0..16], [16..32], [32..64], [64..128]
@@ -81,7 +81,7 @@ L(mm_len_0_or_more_backward):
jbe L(mm_len_0_16_bytes_backward)
cmpl $32, %ecx
- jg L(mm_len_32_or_more_backward)
+ ja L(mm_len_32_or_more_backward)
/* Copy [0..32] and return. */
movdqu (%eax), %xmm0
@@ -92,7 +92,7 @@ L(mm_len_0_or_more_backward):
L(mm_len_32_or_more_backward):
cmpl $64, %ecx
- jg L(mm_len_64_or_more_backward)
+ ja L(mm_len_64_or_more_backward)
/* Copy [0..64] and return. */
movdqu (%eax), %xmm0
@@ -107,7 +107,7 @@ L(mm_len_32_or_more_backward):
L(mm_len_64_or_more_backward):
cmpl $128, %ecx
- jg L(mm_len_128_or_more_backward)
+ ja L(mm_len_128_or_more_backward)
/* Copy [0..128] and return. */
movdqu (%eax), %xmm0
@@ -132,7 +132,7 @@ L(mm_len_128_or_more_backward):
add %ecx, %eax
cmp %edx, %eax
movl SRC(%esp), %eax
- jle L(forward)
+ jbe L(forward)
PUSH (%esi)
PUSH (%edi)
PUSH (%ebx)
@@ -269,7 +269,7 @@ L(check_forward):
add %edx, %ecx
cmp %eax, %ecx
movl LEN(%esp), %ecx
- jle L(forward)
+ jbe L(forward)
/* Now do checks for lengths. We do [0..16], [0..32], [0..64], [0..128]
separately. */
--
WBR,
Andrew