[PATCH 3/3] makedumpfile: Add support for MM randomization

[Atsushi Kumagai]

>> > 	/*
>> > 	 * On linux-2.6.26, MAX_PHYSMEM_BITS is changed to 44 from 40.
>> >@@ -159,22 +160,13 @@ get_versiondep_info_x86_64(void)
>> > 	else
>> > 		info->max_physmem_bits  = _MAX_PHYSMEM_BITS_2_6_31;
>> >
>> >-	if (info->kernel_version < KERNEL_VERSION(2, 6, 27))
>> >-		info->page_offset = __PAGE_OFFSET_ORIG;
>> >-	else
>> >-		info->page_offset = __PAGE_OFFSET_2_6_27;
>> >+	info->page_offset = NUMBER(page_offset);
>> >
>> >-	if (info->kernel_version < KERNEL_VERSION(2, 6, 31)) {
>> >-		info->vmalloc_start = VMALLOC_START_ORIG;
>> >-		info->vmalloc_end   = VMALLOC_END_ORIG;
>> >-		info->vmemmap_start = VMEMMAP_START_ORIG;
>> >-		info->vmemmap_end   = VMEMMAP_END_ORIG;
>> >-	} else {
>> >-		info->vmalloc_start = VMALLOC_START_2_6_31;
>> >-		info->vmalloc_end   = VMALLOC_END_2_6_31;
>> >-		info->vmemmap_start = VMEMMAP_START_2_6_31;
>> >-		info->vmemmap_end   = VMEMMAP_END_2_6_31;
>> >-	}
>>
>> These *_END_* are no longer used, it's better to remove the definitions
>> of them.
>
>
>Seems is_vmalloc_addr_x86_64 still needs VMALLOC_END and VMEMMAP_END to
>make a judgement.

Yes, VMALLOC_END and VMEMMAP_END are necessary, but what I mentioned were
VMALLOC_END_ORIG, VMEMMAP_END_ORIG , VMALLOC_END_2_6_31 and VMEMMAP_END_2_6_31.
The symbols were used only to initialize info->vmalloc_end and info->vmemmap_end,
so they will be unnecessary by this patch.

>> >+
>> >+	info->vmalloc_start = NUMBER(vmalloc_start);
>> >+	info->vmalloc_end   = info->vmalloc_start + VMALLOC_SIZE - 1;
>> >+	info->vmemmap_start = NUMBER(vmemmap_start);
>> >+	info->vmemmap_end   = info->vmemmap_start + VMEMMAP_SIZE - 1;

Thanks,
Atsushi Kumagai

>> > 	return TRUE;
>> > }
>> >diff --git a/makedumpfile.c b/makedumpfile.c
>> >index 2713f8a..6b0c6ab 100644
>> >--- a/makedumpfile.c
>> >+++ b/makedumpfile.c
>> >@@ -1985,6 +1985,7 @@ get_value_for_old_linux(void)
>> > 			NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE) =
>> > 			PAGE_BUDDY_MAPCOUNT_VALUE_v2_6_39_to_latest_version;
>> > 	}
>> >+	ERRMSG("info->kernel_version=%d\n", info->kernel_version);
>>
>> Is this just a debug message ?
>
>Yes, sorry for this. Will remove it.
>
>>
>> > #ifdef __x86_64__
>> > 	if (NUMBER(KERNEL_IMAGE_SIZE) == NOT_FOUND_NUMBER) {
>> > 		if (info->kernel_version < KERNEL_VERSION(2, 6, 26))
>> >@@ -1992,6 +1993,26 @@ get_value_for_old_linux(void)
>> > 		else
>> > 			NUMBER(KERNEL_IMAGE_SIZE) = KERNEL_IMAGE_SIZE_2_6_26;
>> > 	}
>> >+	if (NUMBER(page_offset) == NOT_FOUND_NUMBER) {
>> >+		if (info->kernel_version < KERNEL_VERSION(2, 6, 27))
>> >+			NUMBER(page_offset) = __PAGE_OFFSET_ORIG;
>> >+		else
>> >+			NUMBER(page_offset) = __PAGE_OFFSET_2_6_27;
>> >+	}
>> >+	if (NUMBER(vmalloc_start) == NOT_FOUND_NUMBER) {
>> >+		if (info->kernel_version < KERNEL_VERSION(2, 6, 31)) {
>> >+			NUMBER(vmalloc_start) = VMALLOC_START_ORIG;
>> >+		} else {
>> >+			NUMBER(vmalloc_start) = VMALLOC_START_2_6_31;
>> >+		}
>> >+	}
>> >+	if (NUMBER(vmemmap_start) == NOT_FOUND_NUMBER) {
>> >+		if (info->kernel_version < KERNEL_VERSION(2, 6, 31))
>> >+			NUMBER(vmemmap_start) = VMEMMAP_START_ORIG;
>> >+		else
>> >+			NUMBER(vmemmap_start) = VMEMMAP_START_2_6_31;
>> >+	}
>> >+
>>
>> (I should have said this when you post the early kaslr patch.)
>> This logic is only for x86_64, I don't like to take it out to
>> here(general pass) with #ifdef. Is there any necessity to write
>> this code here ?
>
>Yes, you are right. I plan to put them into get_versiondep_info_x86_64.
>>
>> > #endif
>> > 	if (SIZE(pageflags) == NOT_FOUND_STRUCTURE) {
>> > 		if (info->kernel_version >= KERNEL_VERSION(2, 6, 27))
>> >@@ -2249,6 +2270,9 @@ write_vmcoreinfo_data(void)
>> >
>> > 	WRITE_NUMBER("PAGE_BUDDY_MAPCOUNT_VALUE", PAGE_BUDDY_MAPCOUNT_VALUE);
>> > 	WRITE_NUMBER("KERNEL_IMAGE_SIZE", KERNEL_IMAGE_SIZE);
>> >+	WRITE_NUMBER("PAGE_OFFSET", page_offset);
>> >+	WRITE_NUMBER("VMALLOC_START", vmalloc_start);
>> >+	WRITE_NUMBER("VMEMMAP_START", vmemmap_start);
>> >
>> > 	WRITE_NUMBER("HUGETLB_PAGE_DTOR", HUGETLB_PAGE_DTOR);
>> >
>> >@@ -2595,6 +2619,9 @@ read_vmcoreinfo(void)
>> >
>> > 	READ_NUMBER("PAGE_BUDDY_MAPCOUNT_VALUE", PAGE_BUDDY_MAPCOUNT_VALUE);
>> > 	READ_NUMBER("KERNEL_IMAGE_SIZE", KERNEL_IMAGE_SIZE);
>> >+	READ_NUMBER("PAGE_OFFSET", page_offset);
>> >+	READ_NUMBER("VMALLOC_START", vmalloc_start);
>> >+	READ_NUMBER("VMEMMAP_START", vmemmap_start);
>> >
>> > 	READ_NUMBER("HUGETLB_PAGE_DTOR", HUGETLB_PAGE_DTOR);
>> >
>> >@@ -3826,7 +3853,7 @@ initial(void)
>> > 		debug_info = TRUE;
>> > 	}
>> >
>> >-	info->kernel_version = get_kernel_version(info.release);
>> >+	info->kernel_version = get_kernel_version(info->release);
>>
>> Why don't you write "info->release" in [PATCH 1/3] ?
>Yes, will do.
>
>Thanks for your comments and great suggestions!
>
>Thanks
>Baoquan
>
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