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CVE-2021-47256— mm/memory-failure: make sure wait for page writeback in memory_failure

EPSS 0.02% · P4
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I. Basic Information for CVE-2021-47256

Vulnerability Information

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Vulnerability Title
mm/memory-failure: make sure wait for page writeback in memory_failure
Source: NVD (National Vulnerability Database)
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: mm/memory-failure: make sure wait for page writeback in memory_failure Our syzkaller trigger the "BUG_ON(!list_empty(&inode->i_wb_list))" in clear_inode: kernel BUG at fs/inode.c:519! Internal error: Oops - BUG: 0 [#1] SMP Modules linked in: Process syz-executor.0 (pid: 249, stack limit = 0x00000000a12409d7) CPU: 1 PID: 249 Comm: syz-executor.0 Not tainted 4.19.95 Hardware name: linux,dummy-virt (DT) pstate: 80000005 (Nzcv daif -PAN -UAO) pc : clear_inode+0x280/0x2a8 lr : clear_inode+0x280/0x2a8 Call trace: clear_inode+0x280/0x2a8 ext4_clear_inode+0x38/0xe8 ext4_free_inode+0x130/0xc68 ext4_evict_inode+0xb20/0xcb8 evict+0x1a8/0x3c0 iput+0x344/0x460 do_unlinkat+0x260/0x410 __arm64_sys_unlinkat+0x6c/0xc0 el0_svc_common+0xdc/0x3b0 el0_svc_handler+0xf8/0x160 el0_svc+0x10/0x218 Kernel panic - not syncing: Fatal exception A crash dump of this problem show that someone called __munlock_pagevec to clear page LRU without lock_page: do_mmap -> mmap_region -> do_munmap -> munlock_vma_pages_range -> __munlock_pagevec. As a result memory_failure will call identify_page_state without wait_on_page_writeback. And after truncate_error_page clear the mapping of this page. end_page_writeback won't call sb_clear_inode_writeback to clear inode->i_wb_list. That will trigger BUG_ON in clear_inode! Fix it by checking PageWriteback too to help determine should we skip wait_on_page_writeback.
Source: NVD (National Vulnerability Database)
CVSS Information
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Type
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞。攻击者利用该漏洞导致内核错误。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

VendorProductAffected VersionsCPESubscribe
LinuxLinux 0bc1f8b0682caa39f45ce1e0228ebf43acb46111 ~ d05267fd27a5c4f54e06daefa3035995d765ca0c -
LinuxLinux 3.16 -

II. Public POCs for CVE-2021-47256

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III. Intelligence Information for CVE-2021-47256

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Same Patch Batch · Linux · 2024-05-21 · 361 CVEs total

CVE-2021-47432lib/generic-radix-tree.c: Don't overflow in peek()
CVE-2023-52760gfs2: Fix slab-use-after-free in gfs2_qd_dealloc
CVE-2023-52757smb: client: fix potential deadlock when releasing mids
CVE-2023-52755ksmbd: fix slab out of bounds write in smb_inherit_dacl()
CVE-2023-52754media: imon: fix access to invalid resource for the second interface
CVE-2023-52753drm/amd/display: Avoid NULL dereference of timing generator
CVE-2023-52752smb: client: fix use-after-free bug in cifs_debug_data_proc_show()
CVE-2023-52751smb: client: fix use-after-free in smb2_query_info_compound()
CVE-2023-52750arm64: Restrict CPU_BIG_ENDIAN to GNU as or LLVM IAS 15.x or newer
CVE-2023-52749spi: Fix null dereference on suspend
CVE-2023-52748f2fs: avoid format-overflow warning
CVE-2022-48710drm/radeon: fix a possible null pointer dereference
CVE-2023-52742net: USB: Fix wrong-direction WARNING in plusb.c
CVE-2023-52738drm/amdgpu/fence: Fix oops due to non-matching drm_sched init/fini
CVE-2023-52740powerpc/64s/interrupt: Fix interrupt exit race with security mitigation switch
CVE-2023-52739Fix page corruption caused by racy check in __free_pages
CVE-2023-52741cifs: Fix use-after-free in rdata->read_into_pages()
CVE-2023-52743ice: Do not use WQ_MEM_RECLAIM flag for workqueue
CVE-2023-52746xfrm/compat: prevent potential spectre v1 gadget in xfrm_xlate32_attr()
CVE-2023-52747IB/hfi1: Restore allocated resources on failed copyout

Showing top 20 of 361 CVEs. View all on vendor page → →

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