CVE-2023-52560

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

mm/damon/vaddr-test: fix memory leak in damondotestapplythree_regions()

When CONFIGDAMONVADDRKUNITTEST=y and making CONFIGDEBUGKMEMLEAK=y and CONFIGDEBUGKMEMLEAKAUTOSCAN=y, the below memory leak is detected.

Since commit 9f86d624292c ("mm/damon/vaddr-test: remove unnecessary variables"), the damondestroyctx() is removed, but still call damonnewtarget() and damonnewregion(), the damonregion which is allocated by kmemcachealloc() in damonnewregion() and the damontarget which is allocated by kmalloc in damonnewtarget() are not freed. And the damonregion which is allocated in damonnewregion() in damonset_regions() is also not freed.

So use damondestroytarget to free all the damonregions and damontarget.

unreferenced object 0xffff888107c9a940 (size 64):
  comm "kunit_try_catch", pid 1069, jiffies 4294670592 (age 732.761s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 06 00 00 00 6b 6b 6b 6b  ............kkkk
    60 c7 9c 07 81 88 ff ff f8 cb 9c 07 81 88 ff ff  `...............
  backtrace:
    [<ffffffff817e0167>] kmalloc_trace+0x27/0xa0
    [<ffffffff819c11cf>] damon_new_target+0x3f/0x1b0
    [<ffffffff819c7d55>] damon_do_test_apply_three_regions.constprop.0+0x95/0x3e0
    [<ffffffff819c82be>] damon_test_apply_three_regions1+0x21e/0x260
    [<ffffffff829fce6a>] kunit_generic_run_threadfn_adapter+0x4a/0x90
    [<ffffffff81237cf6>] kthread+0x2b6/0x380
    [<ffffffff81097add>] ret_from_fork+0x2d/0x70
    [<ffffffff81003791>] ret_from_fork_asm+0x11/0x20
unreferenced object 0xffff8881079cc740 (size 56):
  comm "kunit_try_catch", pid 1069, jiffies 4294670592 (age 732.761s)
  hex dump (first 32 bytes):
    05 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00  ................
    6b 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 6b 6b 6b 6b  kkkkkkkk....kkkk
  backtrace:
    [<ffffffff819bc492>] damon_new_region+0x22/0x1c0
    [<ffffffff819c7d91>] damon_do_test_apply_three_regions.constprop.0+0xd1/0x3e0
    [<ffffffff819c82be>] damon_test_apply_three_regions1+0x21e/0x260
    [<ffffffff829fce6a>] kunit_generic_run_threadfn_adapter+0x4a/0x90
    [<ffffffff81237cf6>] kthread+0x2b6/0x380
    [<ffffffff81097add>] ret_from_fork+0x2d/0x70
    [<ffffffff81003791>] ret_from_fork_asm+0x11/0x20
unreferenced object 0xffff888107c9ac40 (size 64):
  comm "kunit_try_catch", pid 1071, jiffies 4294670595 (age 732.843s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 06 00 00 00 6b 6b 6b 6b  ............kkkk
    a0 cc 9c 07 81 88 ff ff 78 a1 76 07 81 88 ff ff  ........x.v.....
  backtrace:
    [<ffffffff817e0167>] kmalloc_trace+0x27/0xa0
    [<ffffffff819c11cf>] damon_new_target+0x3f/0x1b0
    [<ffffffff819c7d55>] damon_do_test_apply_three_regions.constprop.0+0x95/0x3e0
    [<ffffffff819c851e>] damon_test_apply_three_regions2+0x21e/0x260
    [<ffffffff829fce6a>] kunit_generic_run_threadfn_adapter+0x4a/0x90
    [<ffffffff81237cf6>] kthread+0x2b6/0x380
    [<ffffffff81097add>] ret_from_fork+0x2d/0x70
    [<ffffffff81003791>] ret_from_fork_asm+0x11/0x20
unreferenced object 0xffff8881079ccc80 (size 56):
  comm "kunit_try_catch", pid 1071, jiffies 4294670595 (age 732.843s)
  hex dump (first 32 bytes):
    05 00 00 00 00 00 00 00 14 00 00 00 00 00 00 00  ................
    6b 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 6b 6b 6b 6b  kkkkkkkk....kkkk
  backtrace:
    [<ffffffff819bc492>] damon_new_region+0x22/0x1c0
    [<ffffffff819c7d91>] damon_do_test_apply_three_regions.constprop.0+0xd1/0x3e0
    [<ffffffff819c851e>] damon_test_apply_three_regions2+0x21e/0x260
    [<ffffffff829fce6a>] kunit_generic_run_threadfn_adapter+0x4a/0x90
    [<ffffffff81237cf6>] kthread+0x2b6/0x380
    [<ffffffff81097add>] ret_from_fork+0x2d/0x70
    [&lt;ffff

---truncated---