| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-36028: mm/hugetlb: fix DEBUG_LOCKS_WARN_ON(1) when dissolve_free_hugetlb_folio() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| mm/hugetlb: fix DEBUG_LOCKS_WARN_ON(1) when dissolve_free_hugetlb_folio() |
| |
| When I did memory failure tests recently, below warning occurs: |
| |
| DEBUG_LOCKS_WARN_ON(1) |
| WARNING: CPU: 8 PID: 1011 at kernel/locking/lockdep.c:232 __lock_acquire+0xccb/0x1ca0 |
| Modules linked in: mce_inject hwpoison_inject |
| CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3 |
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 |
| RIP: 0010:__lock_acquire+0xccb/0x1ca0 |
| RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082 |
| RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8 |
| RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0 |
| RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb |
| R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10 |
| R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004 |
| FS: 00007ff9f32aa740(0000) GS:ffffa1ce5fc00000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 00007ff9f3134ba0 CR3: 00000008484e4000 CR4: 00000000000006f0 |
| Call Trace: |
| <TASK> |
| lock_acquire+0xbe/0x2d0 |
| _raw_spin_lock_irqsave+0x3a/0x60 |
| hugepage_subpool_put_pages.part.0+0xe/0xc0 |
| free_huge_folio+0x253/0x3f0 |
| dissolve_free_huge_page+0x147/0x210 |
| __page_handle_poison+0x9/0x70 |
| memory_failure+0x4e6/0x8c0 |
| hard_offline_page_store+0x55/0xa0 |
| kernfs_fop_write_iter+0x12c/0x1d0 |
| vfs_write+0x380/0x540 |
| ksys_write+0x64/0xe0 |
| do_syscall_64+0xbc/0x1d0 |
| entry_SYSCALL_64_after_hwframe+0x77/0x7f |
| RIP: 0033:0x7ff9f3114887 |
| RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 |
| RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887 |
| RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001 |
| RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff |
| R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c |
| R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00 |
| </TASK> |
| Kernel panic - not syncing: kernel: panic_on_warn set ... |
| CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3 |
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 |
| Call Trace: |
| <TASK> |
| panic+0x326/0x350 |
| check_panic_on_warn+0x4f/0x50 |
| __warn+0x98/0x190 |
| report_bug+0x18e/0x1a0 |
| handle_bug+0x3d/0x70 |
| exc_invalid_op+0x18/0x70 |
| asm_exc_invalid_op+0x1a/0x20 |
| RIP: 0010:__lock_acquire+0xccb/0x1ca0 |
| RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082 |
| RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8 |
| RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0 |
| RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb |
| R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10 |
| R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004 |
| lock_acquire+0xbe/0x2d0 |
| _raw_spin_lock_irqsave+0x3a/0x60 |
| hugepage_subpool_put_pages.part.0+0xe/0xc0 |
| free_huge_folio+0x253/0x3f0 |
| dissolve_free_huge_page+0x147/0x210 |
| __page_handle_poison+0x9/0x70 |
| memory_failure+0x4e6/0x8c0 |
| hard_offline_page_store+0x55/0xa0 |
| kernfs_fop_write_iter+0x12c/0x1d0 |
| vfs_write+0x380/0x540 |
| ksys_write+0x64/0xe0 |
| do_syscall_64+0xbc/0x1d0 |
| entry_SYSCALL_64_after_hwframe+0x77/0x7f |
| RIP: 0033:0x7ff9f3114887 |
| RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 |
| RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887 |
| RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001 |
| RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff |
| R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c |
| R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00 |
| </TASK> |
| |
| After git bisecting and digging into the code, I believe the root cause is |
| that _deferred_list field of folio is unioned with _hugetlb_subpool field. |
| In __update_and_free_hugetlb_folio(), folio->_deferred_list is |
| initialized leading to corrupted folio->_hugetlb_subpool when folio is |
| hugetlb. Later free_huge_folio() will use _hugetlb_subpool and above |
| warning happens. |
| |
| But it is assumed hugetlb flag must have been cleared when calling |
| folio_put() in update_and_free_hugetlb_folio(). This assumption is broken |
| due to below race: |
| |
| CPU1 CPU2 |
| dissolve_free_huge_page update_and_free_pages_bulk |
| update_and_free_hugetlb_folio hugetlb_vmemmap_restore_folios |
| folio_clear_hugetlb_vmemmap_optimized |
| clear_flag = folio_test_hugetlb_vmemmap_optimized |
| if (clear_flag) <-- False, it's already cleared. |
| __folio_clear_hugetlb(folio) <-- Hugetlb is not cleared. |
| folio_put |
| free_huge_folio <-- free_the_page is expected. |
| list_for_each_entry() |
| __folio_clear_hugetlb <-- Too late. |
| |
| Fix this issue by checking whether folio is hugetlb directly instead of |
| checking clear_flag to close the race window. |
| |
| The Linux kernel CVE team has assigned CVE-2024-36028 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.1.47 with commit 1b4ce2952b4f33e198d5e993acff0611dff1e399 and fixed in 6.1.91 with commit 2effe407f7563add41750fd7e03da4ea44b98099 |
| Issue introduced in 6.5 with commit 32c877191e022b55fe3a374f3d7e9fb5741c514d and fixed in 6.6.31 with commit 7e0a322877416e8c648819a8e441cf8c790b2cce |
| Issue introduced in 6.5 with commit 32c877191e022b55fe3a374f3d7e9fb5741c514d and fixed in 6.8.9 with commit 9c9b32d46afab2d911897914181c488954012300 |
| Issue introduced in 6.5 with commit 32c877191e022b55fe3a374f3d7e9fb5741c514d and fixed in 6.9 with commit 52ccdde16b6540abe43b6f8d8e1e1ec90b0983af |
| Issue introduced in 6.4.11 with commit 9a1a43a0e7e96911eaa00ad20b20f2edefb31d8a |
| |
| 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-2024-36028 |
| 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: |
| mm/hugetlb.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/2effe407f7563add41750fd7e03da4ea44b98099 |
| https://git.kernel.org/stable/c/7e0a322877416e8c648819a8e441cf8c790b2cce |
| https://git.kernel.org/stable/c/9c9b32d46afab2d911897914181c488954012300 |
| https://git.kernel.org/stable/c/52ccdde16b6540abe43b6f8d8e1e1ec90b0983af |
