CVE: CVE-2024-56566
Published: 2024-12-27
Description: In the Linux kernel, the following vulnerability has been resolved:

mm/slub: Avoid list corruption when removing a slab from the full list

Boot with slub_debug=UFPZ.

If allocated object failed in alloc_consistency_checks, all objects of
the slab will be marked as used, and then the slab will be removed from
the partial list.

When an object belonging to the slab got freed later, the remove_full()
function is called. Because the slab is neither on the partial list nor
on the full list, it eventually lead to a list corruption (actually a
list poison being detected).

So we need to mark and isolate the slab page with metadata corruption,
do not put it back in circulation.

Because the debug caches avoid all the fastpaths, reusing the frozen bit
to mark slab page with metadata corruption seems to be fine.

[ 4277.385669] list_del corruption, ffffea00044b3e50->next is LIST_POISON1 (dead[PII_REDACTED]00)
[ 4277.387023] ------------[ cut here ]------------
[ 4277.387880] kernel BUG at lib/list_debug.c:56!
[ 4277.388680] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[ 4277.389562] CPU: 5 PID: 90 Comm: kworker/5:1 Kdump: loaded Tainted: G           OE      6.6.1-1 #1
[ 4277.392113] Workqueue: xfs-inodegc/vda1 xfs_inodegc_worker [xfs]
[ 4277.393551] RIP: 0010:__list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.394518] Code: 48 91 82 e8 37 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 28 49 91 82 e8 26 f9 9a ff 0f 0b 48 89 fe 48 c7 c7 58 49 91
[ 4277.397292] RSP: 0018:ffffc90000333b38 EFLAGS: 00010082
[ 4277.398202] RAX:[PII_REDACTED]00004e RBX: ffffea00044b3e50 RCX: [PII_REDACTED]
[ 4277.399340] RDX: [PII_REDACTED] RSI: ffffffff828f8715 RDI: 00000000ffffffff
[ 4277.400545] RBP: ffffea00044b3e40 R08: [PII_REDACTED] R09: ffffc900003339f0
[ 4277.401710] R10: [PII_REDACTED] R11: ffffffff82d44088 R12: ffff888112cf9910
[ 4277.402887] R13: [PII_REDACTED] R14: [PII_REDACTED] R15: ffff[PII_REDACTED]c0
[ 4277.404049] FS:  [PII_REDACTED](0000) GS:ffff88842fd40000(0000) knlGS:[PII_REDACTED]
[ 4277.405357] CS:  0010 DS: 0000 ES: 0000 CR0: [PII_REDACTED]
[ 4277.406389] CR2: 00007f2ad0b24000 CR3:[PII_REDACTED]a3a006 CR4:[PII_REDACTED]7706e0
[ 4277.407589] DR0: [PII_REDACTED] DR1: [PII_REDACTED] DR2: [PII_REDACTED]
[ 4277.408780] DR3: [PII_REDACTED] DR6: 00000000fffe0ff0 DR7: [PII_REDACTED]
[ 4277.410000] PKRU: 55555554
[ 4277.410645] Call Trace:
[ 4277.411234]  <TASK>
[ 4277.411777]  ? die+0x32/0x80
[ 4277.412439]  ? do_trap+0xd6/0x100
[ 4277.413150]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.414158]  ? do_error_trap+0x6a/0x90
[ 4277.414948]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.415915]  ? exc_invalid_op+0x4c/0x60
[ 4277.416710]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.417675]  ? asm_exc_invalid_op+0x16/0x20
[ 4277.418482]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.419466]  ? __list_del_entry_valid_or_report+0x7b/0xc0
[ 4277.420410]  free_to_partial_list+0x515/0x5e0
[ 4277.421242]  ? xfs_iext_remove+0x41a/0xa10 [xfs]
[ 4277.422298]  xfs_iext_remove+0x41a/0xa10 [xfs]
[ 4277.423316]  ? xfs_inodegc_worker+0xb4/0x1a0 [xfs]
[ 4277.424383]  xfs_bmap_del_extent_delay+0x4fe/0x7d0 [xfs]
[ 4277.425490]  __xfs_bunmapi+0x50d/0x840 [xfs]
[ 4277.426445]  xfs_itruncate_extents_flags+0x13a/0x490 [xfs]
[ 4277.427553]  xfs_inactive_truncate+0xa3/0x120 [xfs]
[ 4277.428567]  xfs_inactive+0x22d/0x290 [xfs]
[ 4277.429500]  xfs_inodegc_worker+0xb4/0x1a0 [xfs]
[ 4277.430479]  process_one_work+0x171/0x340
[ 4277.431227]  worker_thread+0x277/0x390
[ 4277.431962]  ? __pfx_worker_thread+0x10/0x10
[ 4277.432752]  kthread+0xf0/0x120
[ 4277.433382]  ? __pfx_kthread+0x10/0x10
[ 4277.434134]  ret_from_fork+0x2d/0x50
[ 4277.434837]  ? __pfx_kthread+0x10/0x10
[ 4277.435566]  ret_from_fork_asm+0x1b/0x30
[ 4277.436280]  </TASK>
CVSS Score: 5.5 (MEDIUM)
CWE: CWE-401
References: https://git.kernel.org/stable/c/33a213c04faff6c3a7fe77e947db81bc7270fe32; https://git.kernel.org/stable/c/943c0f601cd28c1073b92b5f944c6c6c2643e709; https://git.kernel.org/stable/c/dbc16915279a548a204154368da23d402c141c81