Subject: CVE-2024-27061: crypto: sun8i-ce - Fix use after free in unprepare

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

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

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

crypto: sun8i-ce - Fix use after free in unprepare

sun8i_ce_cipher_unprepare should be called before
crypto_finalize_skcipher_request, because client callbacks may
immediately free memory, that isn't needed anymore. But it will be
used by unprepare after free. Before removing prepare/unprepare
callbacks it was handled by crypto engine in crypto_finalize_request.

Usually that results in a pointer dereference problem during a in
crypto selftest.
 Unable to handle kernel NULL pointer dereference at
                                      virtual address 0000000000000030
 Mem abort info:
   ESR = 0x0000000096000004
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x04: level 0 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=000000004716d000
 [0000000000000030] pgd=0000000000000000, p4d=0000000000000000
 Internal error: Oops: 0000000096000004 [#1] SMP

This problem is detected by KASAN as well.
 ==================================================================
 BUG: KASAN: slab-use-after-free in sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce]
 Read of size 8 at addr ffff00000dcdc040 by task 1c15000.crypto-/373

 Hardware name: Pine64 PinePhone (1.2) (DT)
 Call trace:
  dump_backtrace+0x9c/0x128
  show_stack+0x20/0x38
  dump_stack_lvl+0x48/0x60
  print_report+0xf8/0x5d8
  kasan_report+0x90/0xd0
  __asan_load8+0x9c/0xc0
  sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce]
  crypto_pump_work+0x354/0x620 [crypto_engine]
  kthread_worker_fn+0x244/0x498
  kthread+0x168/0x178
  ret_from_fork+0x10/0x20

 Allocated by task 379:
  kasan_save_stack+0x3c/0x68
  kasan_set_track+0x2c/0x40
  kasan_save_alloc_info+0x24/0x38
  __kasan_kmalloc+0xd4/0xd8
  __kmalloc+0x74/0x1d0
  alg_test_skcipher+0x90/0x1f0
  alg_test+0x24c/0x830
  cryptomgr_test+0x38/0x60
  kthread+0x168/0x178
  ret_from_fork+0x10/0x20

 Freed by task 379:
  kasan_save_stack+0x3c/0x68
  kasan_set_track+0x2c/0x40
  kasan_save_free_info+0x38/0x60
  __kasan_slab_free+0x100/0x170
  slab_free_freelist_hook+0xd4/0x1e8
  __kmem_cache_free+0x15c/0x290
  kfree+0x74/0x100
  kfree_sensitive+0x80/0xb0
  alg_test_skcipher+0x12c/0x1f0
  alg_test+0x24c/0x830
  cryptomgr_test+0x38/0x60
  kthread+0x168/0x178
  ret_from_fork+0x10/0x20

 The buggy address belongs to the object at ffff00000dcdc000
  which belongs to the cache kmalloc-256 of size 256
 The buggy address is located 64 bytes inside of
  freed 256-byte region [ffff00000dcdc000, ffff00000dcdc100)

The Linux kernel CVE team has assigned CVE-2024-27061 to this issue.

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

	Issue introduced in 6.6 with commit 4136212ab18e and fixed in 6.6.24 with commit dc60b25540c8
	Issue introduced in 6.6 with commit 4136212ab18e and fixed in 6.7.12 with commit 51a7d338c212
	Issue introduced in 6.6 with commit 4136212ab18e and fixed in 6.8 with commit 183420038444

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-2024-27061
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:
	drivers/crypto/allwinner/sun8i-ce/sun8i-ce-cipher.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/dc60b25540c82fc4baa95d1458ae96ead21859e0
	https://git.kernel.org/stable/c/51a7d338c212e0640b1aca52ba6590d5bea49879
	https://git.kernel.org/stable/c/183420038444547c149a0fc5f58e792c2752860c