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Remove page level mprotects

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Freeing block mprotects on the page which it turn
may lead to application crash if linker subsequently
tries to modify another block on the page.

Bug: 14895266
Change-Id: I8ff7f5df467d7be184242de652032b3c84e24b76
This commit is contained in:
Dmitriy Ivanov
2014-05-13 18:34:48 -07:00
parent d597d263bc
commit bc23e530c4
3 changed files with 0 additions and 44 deletions
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30
linker/tests/linker_allocator_test.cpp
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@@ -61,8 +61,6 @@ TEST(linker_allocator, test_nominal) {
ptr1->value = 42;
allocator.protect_page(ptr1, PROT_READ);
allocator.free(ptr1);
allocator.free(ptr2);
}
@@ -91,8 +89,6 @@ TEST(linker_allocator, test_larger) {
ASSERT_EQ(ptr1+1, ptr2);
allocator.protect_page(ptr2, PROT_READ);
// lets allocate until we reach next page.
size_t n = kPageSize/sizeof(test_struct_larger) + 1 - 2;
@@ -102,31 +98,6 @@ TEST(linker_allocator, test_larger) {
}
static void protect_one_page() {
LinkerAllocator<test_struct_larger> allocator;
allocator.init();
// number of allocs to reach the end of first page
size_t n = kPageSize/sizeof(test_struct_larger) - 1;
test_struct_larger* page1_ptr = allocator.alloc();
for (size_t i=0; i<n; ++i) {
allocator.alloc();
}
test_struct_larger* page2_ptr = allocator.alloc();
allocator.protect_page(page2_ptr, PROT_READ);
// check that we still have access to page1
page1_ptr->dummy_str[17] = 52;
fprintf(stderr, "trying to access protected page");
// this should result in segmentation fault
page2_ptr->dummy_str[12] = 3;
}
static void protect_all() {
LinkerAllocator<test_struct_larger> allocator;
allocator.init();
@@ -155,7 +126,6 @@ static void protect_all() {
TEST(linker_allocator, test_protect) {
testing::FLAGS_gtest_death_test_style = "threadsafe";
ASSERT_EXIT(protect_one_page(), testing::KilledBySignal(SIGSEGV), "trying to access protected page");
ASSERT_EXIT(protect_all(), testing::KilledBySignal(SIGSEGV), "trying to access protected page");
}