CVE-2024-27070

In the Linux kernel, the following vulnerability has been resolved: f2fs:
fix to avoid use-after-free issue in f2fs_filemap_fault syzbot reports a
f2fs bug as below: BUG: KASAN: slab-use-after-free in
f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49 Read of size 8 at addr
ffff88807bb22680 by task syz-executor184/5058 CPU: 0 PID: 5058 Comm:
syz-executor184 Not tainted 6.7.0-syzkaller-09928-g052d534373b7 #0 Hardware
name: Google Google Compute Engine/Google Compute Engine, BIOS Google
11/17/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description
mm/kasan/report.c:377 [inline] print_report+0x163/0x540
mm/kasan/report.c:488 kasan_report+0x142/0x170 mm/kasan/report.c:601
f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49 __do_fault+0x131/0x450
mm/memory.c:4376 do_shared_fault mm/memory.c:4798 [inline] do_fault
mm/memory.c:4872 [inline] do_pte_missing mm/memory.c:3745 [inline]
handle_pte_fault mm/memory.c:5144 [inline] __handle_mm_fault+0x23b7/0x72b0
mm/memory.c:5285 handle_mm_fault+0x27e/0x770 mm/memory.c:5450
do_user_addr_fault arch/x86/mm/fault.c:1364 [inline] handle_page_fault
arch/x86/mm/fault.c:1507 [inline] exc_page_fault+0x456/0x870
arch/x86/mm/fault.c:1563 asm_exc_page_fault+0x26/0x30
arch/x86/include/asm/idtentry.h:570 The root cause is: in
f2fs_filemap_fault(), vmf->vma may be not alive after filemap_fault(), so
it may cause use-after-free issue when accessing vmf->vma->vm_flags in
trace_f2fs_filemap_fault(). So it needs to keep vm_flags in separated
temporary variable for tracepoint use.