arm64: mm: use untagged address to calculate page index

arm64: mm: use untagged address to calculate page index

Nathan Chancellor reported the below bug:

[    0.149929] BUG: KASAN: invalid-access in change_memory_common+0x258/0x2d0
[    0.151006] Read of size 8 at addr f96680000268a000 by task swapper/0/1
[    0.152031]
[    0.152274] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.18.0-rc1-00012-g37cb0aab9068 #1 PREEMPT
[    0.152288] Hardware name: linux,dummy-virt (DT)
[    0.152292] Call trace:
[    0.152295]  show_stack+0x18/0x30 (C)
[    0.152309]  dump_stack_lvl+0x60/0x80
[    0.152320]  print_report+0x480/0x498
[    0.152331]  kasan_report+0xac/0xf0
[    0.152343]  kasan_check_range+0x90/0xb0
[    0.152353]  __hwasan_load8_noabort+0x20/0x34
[    0.152364]  change_memory_common+0x258/0x2d0
[    0.152375]  set_memory_ro+0x18/0x24
[    0.152386]  bpf_prog_pack_alloc+0x200/0x2e8
[    0.152397]  bpf_jit_binary_pack_alloc+0x78/0x188
[    0.152409]  bpf_int_jit_compile+0xa4c/0xc74
[    0.152420]  bpf_prog_select_runtime+0x1c0/0x2bc
[    0.152430]  bpf_prepare_filter+0x5a4/0x7c0
[    0.152443]  bpf_prog_create+0xa4/0x100
[    0.152454]  ptp_classifier_init+0x80/0xd0
[    0.152465]  sock_init+0x12c/0x178
[    0.152474]  do_one_initcall+0xa0/0x260
[    0.152484]  kernel_init_freeable+0x2d8/0x358
[    0.152495]  kernel_init+0x20/0x140
[    0.152510]  ret_from_fork+0x10/0x20

It is because the KASAN tagged address was used when calculating the page
index. The untagged address should be used.

Fixes: 37cb0aab9068 ("arm64: mm: make linear mapping permission update more robust for patial range")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Yang Shi <yang@os.amperecomputing.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>