KASAN: vmalloc-out-of-bounds Read in acpi_nfit_ctl

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    040a3c33 Merge tag 'iommu-fixes-v5.5-rc5' of git://git.ker..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=120a5d8ee00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7e89bd00623fe71e
dashboard link: https://syzkaller.appspot.com/bug?extid=002f559bf34c2c7467d0
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
userspace arch: i386

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+002f559bf34c2c7467d0@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: vmalloc-out-of-bounds in test_bit  
include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
BUG: KASAN: vmalloc-out-of-bounds in acpi_nfit_ctl+0x47f/0x1840  
drivers/acpi/nfit/core.c:495
Read of size 8 at addr ffffc90002ddbbb8 by task syz-executor.1/5941

CPU: 3 PID: 5941 Comm: syz-executor.1 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS  
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
 __kasan_check_read+0x11/0x20 mm/kasan/common.c:95
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
 acpi_nfit_ctl+0x47f/0x1840 drivers/acpi/nfit/core.c:495
 __nd_ioctl drivers/nvdimm/bus.c:1152 [inline]
 nd_ioctl.isra.0+0xfe2/0x1580 drivers/nvdimm/bus.c:1230
 bus_ioctl+0x59/0x70 drivers/nvdimm/bus.c:1242
 compat_ptr_ioctl+0x6e/0xa0 fs/ioctl.c:788
 __do_compat_sys_ioctl fs/compat_ioctl.c:214 [inline]
 __se_compat_sys_ioctl fs/compat_ioctl.c:142 [inline]
 __ia32_compat_sys_ioctl+0x233/0x610 fs/compat_ioctl.c:142
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f37a39
Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c  
24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90  
90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5d330cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000000560a
RDX: 0000000020000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000


Memory state around the buggy address:
 ffffc90002ddba80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffffc90002ddbb00: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
> ffffc90002ddbb80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
                                        ^
 ffffc90002ddbc00: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffffc90002ddbc80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
==================================================================


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