CVE-2023-52560 mm/damon/vaddr-test: fix memory leak in damon_do_test_apply_three_regions()

What is CVE-2023-52560?

CVE-2023-52560 is a medium-severity denial of service vulnerability in Linux kernel, published on 2 Mar 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

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

When CONFIG_DAMON_VADDR_KUNIT_TEST=y and making CONFIG_DEBUG_KMEMLEAK=y and CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN=y, the below memory leak is detected.

Since commit 9f86d624292c ("mm/damon/vaddr-test: remove unnecessary variables"), the damon_destroy_ctx() is removed, but still call damon_new_target() and damon_new_region(), the damon_region which is allocated by kmem_cache_alloc() in damon_new_region() and the damon_target which is allocated by kmalloc in damon_new_target() are not freed. And the damon_region which is allocated in damon_new_region() in damon_set_regions() is also not freed.

So use damon_destroy_target to free all the damon_regions and damon_target.

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 [<ffff ---truncated---

Weakness: CWE-401

Which versions are affected by CVE-2023-52560?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-52560?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2023-52560 being exploited?

There is no known exploitation of CVE-2023-52560 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-52560, DEBIAN-CVE-2023-52560, GHSA-65mj-5f83-m897, UBUNTU-CVE-2023-52560.