ghsa-qm36-7xcx-862v
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
mm, thp: bail out early in collapse_file for writeback page
Currently collapse_file does not explicitly check PG_writeback, instead, page_has_private and try_to_release_page are used to filter writeback pages. This does not work for xfs with blocksize equal to or larger than pagesize, because in such case xfs has no page->private.
This makes collapse_file bail out early for writeback page. Otherwise, xfs end_page_writeback will panic as follows.
page:fffffe00201bcc80 refcount:0 mapcount:0 mapping:ffff0003f88c86a8 index:0x0 pfn:0x84ef32 aops:xfs_address_space_operations [xfs] ino:30000b7 dentry name:"libtest.so" flags: 0x57fffe0000008027(locked|referenced|uptodate|active|writeback) raw: 57fffe0000008027 ffff80001b48bc28 ffff80001b48bc28 ffff0003f88c86a8 raw: 0000000000000000 0000000000000000 00000000ffffffff ffff0000c3e9a000 page dumped because: VM_BUG_ON_PAGE(((unsigned int) page_ref_count(page) + 127u <= 127u)) page->mem_cgroup:ffff0000c3e9a000 ------------[ cut here ]------------ kernel BUG at include/linux/mm.h:1212! Internal error: Oops - BUG: 0 [#1] SMP Modules linked in: BUG: Bad page state in process khugepaged pfn:84ef32 xfs(E) page:fffffe00201bcc80 refcount:0 mapcount:0 mapping:0 index:0x0 pfn:0x84ef32 libcrc32c(E) rfkill(E) aes_ce_blk(E) crypto_simd(E) ... CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Tainted: ... pstate: 60400005 (nZCv daif +PAN -UAO -TCO BTYPE=--) Call trace: end_page_writeback+0x1c0/0x214 iomap_finish_page_writeback+0x13c/0x204 iomap_finish_ioend+0xe8/0x19c iomap_writepage_end_bio+0x38/0x50 bio_endio+0x168/0x1ec blk_update_request+0x278/0x3f0 blk_mq_end_request+0x34/0x15c virtblk_request_done+0x38/0x74 [virtio_blk] blk_done_softirq+0xc4/0x110 __do_softirq+0x128/0x38c __irq_exit_rcu+0x118/0x150 irq_exit+0x1c/0x30 __handle_domain_irq+0x8c/0xf0 gic_handle_irq+0x84/0x108 el1_irq+0xcc/0x180 arch_cpu_idle+0x18/0x40 default_idle_call+0x4c/0x1a0 cpuidle_idle_call+0x168/0x1e0 do_idle+0xb4/0x104 cpu_startup_entry+0x30/0x9c secondary_start_kernel+0x104/0x180 Code: d4210000 b0006161 910c8021 94013f4d (d4210000) ---[ end trace 4a88c6a074082f8c ]--- Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt
{
"affected": [],
"aliases": [
"CVE-2021-47492"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-22T09:15:11Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm, thp: bail out early in collapse_file for writeback page\n\nCurrently collapse_file does not explicitly check PG_writeback, instead,\npage_has_private and try_to_release_page are used to filter writeback\npages. This does not work for xfs with blocksize equal to or larger\nthan pagesize, because in such case xfs has no page-\u003eprivate.\n\nThis makes collapse_file bail out early for writeback page. Otherwise,\nxfs end_page_writeback will panic as follows.\n\n page:fffffe00201bcc80 refcount:0 mapcount:0 mapping:ffff0003f88c86a8 index:0x0 pfn:0x84ef32\n aops:xfs_address_space_operations [xfs] ino:30000b7 dentry name:\"libtest.so\"\n flags: 0x57fffe0000008027(locked|referenced|uptodate|active|writeback)\n raw: 57fffe0000008027 ffff80001b48bc28 ffff80001b48bc28 ffff0003f88c86a8\n raw: 0000000000000000 0000000000000000 00000000ffffffff ffff0000c3e9a000\n page dumped because: VM_BUG_ON_PAGE(((unsigned int) page_ref_count(page) + 127u \u003c= 127u))\n page-\u003emem_cgroup:ffff0000c3e9a000\n ------------[ cut here ]------------\n kernel BUG at include/linux/mm.h:1212!\n Internal error: Oops - BUG: 0 [#1] SMP\n Modules linked in:\n BUG: Bad page state in process khugepaged pfn:84ef32\n xfs(E)\n page:fffffe00201bcc80 refcount:0 mapcount:0 mapping:0 index:0x0 pfn:0x84ef32\n libcrc32c(E) rfkill(E) aes_ce_blk(E) crypto_simd(E) ...\n CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Tainted: ...\n pstate: 60400005 (nZCv daif +PAN -UAO -TCO BTYPE=--)\n Call trace:\n end_page_writeback+0x1c0/0x214\n iomap_finish_page_writeback+0x13c/0x204\n iomap_finish_ioend+0xe8/0x19c\n iomap_writepage_end_bio+0x38/0x50\n bio_endio+0x168/0x1ec\n blk_update_request+0x278/0x3f0\n blk_mq_end_request+0x34/0x15c\n virtblk_request_done+0x38/0x74 [virtio_blk]\n blk_done_softirq+0xc4/0x110\n __do_softirq+0x128/0x38c\n __irq_exit_rcu+0x118/0x150\n irq_exit+0x1c/0x30\n __handle_domain_irq+0x8c/0xf0\n gic_handle_irq+0x84/0x108\n el1_irq+0xcc/0x180\n arch_cpu_idle+0x18/0x40\n default_idle_call+0x4c/0x1a0\n cpuidle_idle_call+0x168/0x1e0\n do_idle+0xb4/0x104\n cpu_startup_entry+0x30/0x9c\n secondary_start_kernel+0x104/0x180\n Code: d4210000 b0006161 910c8021 94013f4d (d4210000)\n ---[ end trace 4a88c6a074082f8c ]---\n Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt",
"id": "GHSA-qm36-7xcx-862v",
"modified": "2024-05-22T09:31:46Z",
"published": "2024-05-22T09:31:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47492"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5e669d8ab30ab61dec3c36e27b4711f07611e6fc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/69a7fa5cb0de06c8956b040f19a7248c8c8308ca"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/74c42e1baacf206338b1dd6b6199ac964512b5bb"
}
],
"schema_version": "1.4.0",
"severity": []
}
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