Subject: CVE-2023-52770: f2fs: split initial and dynamic conditions for extent_cache

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

f2fs: split initial and dynamic conditions for extent_cache

Let's allocate the extent_cache tree without dynamic conditions to avoid a
missing condition causing a panic as below.

 # create a file w/ a compressed flag
 # disable the compression
 # panic while updating extent_cache

F2FS-fs (dm-64): Swapfile: last extent is not aligned to section
F2FS-fs (dm-64): Swapfile (3) is not align to section: 1) creat(), 2) ioctl(F2FS_IOC_SET_PIN_FILE), 3) fallocate(2097152 * N)
Adding 124996k swap on ./swap-file.  Priority:0 extents:2 across:17179494468k
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write out/common/include/linux/instrumented.h:101 [inline]
BUG: KASAN: null-ptr-deref in atomic_try_cmpxchg_acquire out/common/include/asm-generic/atomic-instrumented.h:705 [inline]
BUG: KASAN: null-ptr-deref in queued_write_lock out/common/include/asm-generic/qrwlock.h:92 [inline]
BUG: KASAN: null-ptr-deref in __raw_write_lock out/common/include/linux/rwlock_api_smp.h:211 [inline]
BUG: KASAN: null-ptr-deref in _raw_write_lock+0x5a/0x110 out/common/kernel/locking/spinlock.c:295
Write of size 4 at addr 0000000000000030 by task syz-executor154/3327

CPU: 0 PID: 3327 Comm: syz-executor154 Tainted: G           O      5.10.185 #1
Hardware name: emulation qemu-x86/qemu-x86, BIOS 2023.01-21885-gb3cc1cd24d 01/01/2023
Call Trace:
 __dump_stack out/common/lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x17e/0x1c4 out/common/lib/dump_stack.c:118
 __kasan_report+0x16c/0x260 out/common/mm/kasan/report.c:415
 kasan_report+0x51/0x70 out/common/mm/kasan/report.c:428
 kasan_check_range+0x2f3/0x340 out/common/mm/kasan/generic.c:186
 __kasan_check_write+0x14/0x20 out/common/mm/kasan/shadow.c:37
 instrument_atomic_read_write out/common/include/linux/instrumented.h:101 [inline]
 atomic_try_cmpxchg_acquire out/common/include/asm-generic/atomic-instrumented.h:705 [inline]
 queued_write_lock out/common/include/asm-generic/qrwlock.h:92 [inline]
 __raw_write_lock out/common/include/linux/rwlock_api_smp.h:211 [inline]
 _raw_write_lock+0x5a/0x110 out/common/kernel/locking/spinlock.c:295
 __drop_extent_tree+0xdf/0x2f0 out/common/fs/f2fs/extent_cache.c:1155
 f2fs_drop_extent_tree+0x17/0x30 out/common/fs/f2fs/extent_cache.c:1172
 f2fs_insert_range out/common/fs/f2fs/file.c:1600 [inline]
 f2fs_fallocate+0x19fd/0x1f40 out/common/fs/f2fs/file.c:1764
 vfs_fallocate+0x514/0x9b0 out/common/fs/open.c:310
 ksys_fallocate out/common/fs/open.c:333 [inline]
 __do_sys_fallocate out/common/fs/open.c:341 [inline]
 __se_sys_fallocate out/common/fs/open.c:339 [inline]
 __x64_sys_fallocate+0xb8/0x100 out/common/fs/open.c:339
 do_syscall_64+0x35/0x50 out/common/arch/x86/entry/common.c:46

The Linux kernel CVE team has assigned CVE-2023-52770 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.2 with commit 72840cccc0a1 and fixed in 6.5.13 with commit 9de787139b02
	Issue introduced in 6.2 with commit 72840cccc0a1 and fixed in 6.6.3 with commit d83309e7e006
	Issue introduced in 6.2 with commit 72840cccc0a1 and fixed in 6.7 with commit f803982190f0
	Issue introduced in 6.1.29 with commit 4377b1d3b19e

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2023-52770
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	fs/f2fs/extent_cache.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/9de787139b0258a5dd1f498780c26d76b61d2958
	https://git.kernel.org/stable/c/d83309e7e006cee8afca83523559017c824fbf7a
	https://git.kernel.org/stable/c/f803982190f0265fd36cf84670aa6daefc2b0768