| 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-2024-40914: mm/huge_memory: don't unpoison huge_zero_folio |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| mm/huge_memory: don't unpoison huge_zero_folio |
| |
| When I did memory failure tests recently, below panic occurs: |
| |
| kernel BUG at include/linux/mm.h:1135! |
| invalid opcode: 0000 [#1] PREEMPT SMP NOPTI |
| CPU: 9 PID: 137 Comm: kswapd1 Not tainted 6.9.0-rc4-00491-gd5ce28f156fe-dirty #14 |
| RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0 |
| RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246 |
| RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8 |
| RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0 |
| RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492 |
| R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000 |
| R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00 |
| FS: 0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0 |
| Call Trace: |
| <TASK> |
| do_shrink_slab+0x14f/0x6a0 |
| shrink_slab+0xca/0x8c0 |
| shrink_node+0x2d0/0x7d0 |
| balance_pgdat+0x33a/0x720 |
| kswapd+0x1f3/0x410 |
| kthread+0xd5/0x100 |
| ret_from_fork+0x2f/0x50 |
| ret_from_fork_asm+0x1a/0x30 |
| </TASK> |
| Modules linked in: mce_inject hwpoison_inject |
| ---[ end trace 0000000000000000 ]--- |
| RIP: 0010:shrink_huge_zero_page_scan+0x168/0x1a0 |
| RSP: 0018:ffff9933c6c57bd0 EFLAGS: 00000246 |
| RAX: 000000000000003e RBX: 0000000000000000 RCX: ffff88f61fc5c9c8 |
| RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff88f61fc5c9c0 |
| RBP: ffffcd7c446b0000 R08: ffffffff9a9405f0 R09: 0000000000005492 |
| R10: 00000000000030ea R11: ffffffff9a9405f0 R12: 0000000000000000 |
| R13: 0000000000000000 R14: 0000000000000000 R15: ffff88e703c4ac00 |
| FS: 0000000000000000(0000) GS:ffff88f61fc40000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: 000055f4da6e9878 CR3: 0000000c71048000 CR4: 00000000000006f0 |
| |
| The root cause is that HWPoison flag will be set for huge_zero_folio |
| without increasing the folio refcnt. But then unpoison_memory() will |
| decrease the folio refcnt unexpectedly as it appears like a successfully |
| hwpoisoned folio leading to VM_BUG_ON_PAGE(page_ref_count(page) == 0) when |
| releasing huge_zero_folio. |
| |
| Skip unpoisoning huge_zero_folio in unpoison_memory() to fix this issue. |
| We're not prepared to unpoison huge_zero_folio yet. |
| |
| The Linux kernel CVE team has assigned CVE-2024-40914 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.15.41 with commit f8f836100fff594cea8a0a027affb9d5520f09a7 and fixed in 5.15.162 with commit 688bb46ad339497b5b7f527b6636d2afe04b46af |
| Issue introduced in 5.18 with commit 478d134e9506c7e9bfe2830ed03dd85e97966313 and fixed in 6.1.95 with commit b2494506f30675245a3e6787281f79601af087bf |
| Issue introduced in 5.18 with commit 478d134e9506c7e9bfe2830ed03dd85e97966313 and fixed in 6.6.35 with commit 0d73477af964dbd7396163a13817baf13940bca9 |
| Issue introduced in 5.18 with commit 478d134e9506c7e9bfe2830ed03dd85e97966313 and fixed in 6.9.6 with commit d72b7711919de49d92a67dfc844a6cf4c23dd794 |
| Issue introduced in 5.18 with commit 478d134e9506c7e9bfe2830ed03dd85e97966313 and fixed in 6.10 with commit fe6f86f4b40855a130a19aa589f9ba7f650423f4 |
| Issue introduced in 5.17.9 with commit 13d9b8cd12f37d133b07ea5b323583e8a0c6b738 |
| |
| 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-2024-40914 |
| 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/memory-failure.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/688bb46ad339497b5b7f527b6636d2afe04b46af |
| https://git.kernel.org/stable/c/b2494506f30675245a3e6787281f79601af087bf |
| https://git.kernel.org/stable/c/0d73477af964dbd7396163a13817baf13940bca9 |
| https://git.kernel.org/stable/c/d72b7711919de49d92a67dfc844a6cf4c23dd794 |
| https://git.kernel.org/stable/c/fe6f86f4b40855a130a19aa589f9ba7f650423f4 |
