| 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-2021-47090: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() |
| |
| Hulk Robot reported a panic in put_page_testzero() when testing |
| madvise() with MADV_SOFT_OFFLINE. The BUG() is triggered when retrying |
| get_any_page(). This is because we keep MF_COUNT_INCREASED flag in |
| second try but the refcnt is not increased. |
| |
| page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) |
| ------------[ cut here ]------------ |
| kernel BUG at include/linux/mm.h:737! |
| invalid opcode: 0000 [#1] PREEMPT SMP |
| CPU: 5 PID: 2135 Comm: sshd Tainted: G B 5.16.0-rc6-dirty #373 |
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 |
| RIP: release_pages+0x53f/0x840 |
| Call Trace: |
| free_pages_and_swap_cache+0x64/0x80 |
| tlb_flush_mmu+0x6f/0x220 |
| unmap_page_range+0xe6c/0x12c0 |
| unmap_single_vma+0x90/0x170 |
| unmap_vmas+0xc4/0x180 |
| exit_mmap+0xde/0x3a0 |
| mmput+0xa3/0x250 |
| do_exit+0x564/0x1470 |
| do_group_exit+0x3b/0x100 |
| __do_sys_exit_group+0x13/0x20 |
| __x64_sys_exit_group+0x16/0x20 |
| do_syscall_64+0x34/0x80 |
| entry_SYSCALL_64_after_hwframe+0x44/0xae |
| Modules linked in: |
| ---[ end trace e99579b570fe0649 ]--- |
| RIP: 0010:release_pages+0x53f/0x840 |
| |
| The Linux kernel CVE team has assigned CVE-2021-47090 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.10 with commit b94e02822debdf0cc473556aad7dcc859f216653 and fixed in 5.10.89 with commit 1f207076740101fed87074a6bc924dbe806f08a5 |
| Issue introduced in 5.10 with commit b94e02822debdf0cc473556aad7dcc859f216653 and fixed in 5.15.12 with commit c691e7575eff76e563b0199c23ec46bd454f43e3 |
| Issue introduced in 5.10 with commit b94e02822debdf0cc473556aad7dcc859f216653 and fixed in 5.16 with commit 2a57d83c78f889bf3f54eede908d0643c40d5418 |
| |
| 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-2021-47090 |
| 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/1f207076740101fed87074a6bc924dbe806f08a5 |
| https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3 |
| https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418 |
