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CVE-2024-40949— mm: shmem: fix getting incorrect lruvec when replacing a shmem folio

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

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，该漏洞源于 mm:shmem 组件在替换 shmem folio 时存在获取错误 lruvec 的问题。

CVSS 7.8 · High EPSS 0.22% · P12

Affected Version Matrix 6

VendorProduct Version RangeStatus
Linux Linux 85ce2c517ade0d51b7ad95f2e88be9bbe294379a< 8c6c3719ebb7913f8a665d11816d2e38b0eadbab affected
85ce2c517ade0d51b7ad95f2e88be9bbe294379a< 9094b4a1c76cfe84b906cc152bab34d4ba26fa5c affected
6.7 affected
< 6.7 unaffected
6.9.7≤ 6.9.* unaffected
6.10≤ * unaffected
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I. Basic Information for CVE-2024-40949

Vulnerability Information
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Vulnerability Title
mm: shmem: fix getting incorrect lruvec when replacing a shmem folio
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: mm: shmem: fix getting incorrect lruvec when replacing a shmem folio When testing shmem swapin, I encountered the warning below on my machine. The reason is that replacing an old shmem folio with a new one causes mem_cgroup_migrate() to clear the old folio's memcg data. As a result, the old folio cannot get the correct memcg's lruvec needed to remove itself from the LRU list when it is being freed. This could lead to possible serious problems, such as LRU list crashes due to holding the wrong LRU lock, and incorrect LRU statistics. To fix this issue, we can fallback to use the mem_cgroup_replace_folio() to replace the old shmem folio. [ 5241.100311] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5d9960 [ 5241.100317] head: order:4 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 5241.100319] flags: 0x17fffe0000040068(uptodate|lru|head|swapbacked|node=0|zone=2|lastcpupid=0x3ffff) [ 5241.100323] raw: 17fffe0000040068 fffffdffd6687948 fffffdffd69ae008 0000000000000000 [ 5241.100325] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 5241.100326] head: 17fffe0000040068 fffffdffd6687948 fffffdffd69ae008 0000000000000000 [ 5241.100327] head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 5241.100328] head: 17fffe0000000204 fffffdffd6665801 ffffffffffffffff 0000000000000000 [ 5241.100329] head: 0000000a00000010 0000000000000000 00000000ffffffff 0000000000000000 [ 5241.100330] page dumped because: VM_WARN_ON_ONCE_FOLIO(!memcg && !mem_cgroup_disabled()) [ 5241.100338] ------------[ cut here ]------------ [ 5241.100339] WARNING: CPU: 19 PID: 78402 at include/linux/memcontrol.h:775 folio_lruvec_lock_irqsave+0x140/0x150 [...] [ 5241.100374] pc : folio_lruvec_lock_irqsave+0x140/0x150 [ 5241.100375] lr : folio_lruvec_lock_irqsave+0x138/0x150 [ 5241.100376] sp : ffff80008b38b930 [...] [ 5241.100398] Call trace: [ 5241.100399] folio_lruvec_lock_irqsave+0x140/0x150 [ 5241.100401] __page_cache_release+0x90/0x300 [ 5241.100404] __folio_put+0x50/0x108 [ 5241.100406] shmem_replace_folio+0x1b4/0x240 [ 5241.100409] shmem_swapin_folio+0x314/0x528 [ 5241.100411] shmem_get_folio_gfp+0x3b4/0x930 [ 5241.100412] shmem_fault+0x74/0x160 [ 5241.100414] __do_fault+0x40/0x218 [ 5241.100417] do_shared_fault+0x34/0x1b0 [ 5241.100419] do_fault+0x40/0x168 [ 5241.100420] handle_pte_fault+0x80/0x228 [ 5241.100422] __handle_mm_fault+0x1c4/0x440 [ 5241.100424] handle_mm_fault+0x60/0x1f0 [ 5241.100426] do_page_fault+0x120/0x488 [ 5241.100429] do_translation_fault+0x4c/0x68 [ 5241.100431] do_mem_abort+0x48/0xa0 [ 5241.100434] el0_da+0x38/0xc0 [ 5241.100436] el0t_64_sync_handler+0x68/0xc0 [ 5241.100437] el0t_64_sync+0x14c/0x150 [ 5241.100439] ---[ end trace 0000000000000000 ]--- [baolin.wang@linux.alibaba.com: remove less helpful comments, per Matthew]
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
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，该漏洞源于 mm:shmem 组件在替换 shmem folio 时存在获取错误 lruvec 的问题。
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

Vendor Product Affected Versions CPE Subscribe
Linux Linux 85ce2c517ade0d51b7ad95f2e88be9bbe294379a ~ 8c6c3719ebb7913f8a665d11816d2e38b0eadbab -
Linux Linux 6.7 -

II. Public POCs for CVE-2024-40949

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III. Intelligence Information for CVE-2024-40949

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Other References for CVE-2024-40949 (2)

Same Patch Batch · Linux · 2024-07-12 · 122 CVEs total

CVE-2024-40937 9.8 CRITICAL gve: Clear napi->skb before dev_kfree_skb_any()
CVE-2024-40907 9.8 CRITICAL ionic: fix kernel panic in XDP_TX action
CVE-2024-40999 9.8 CRITICAL net: ena: Add validation for completion descriptors consistency
CVE-2024-40923 9.8 CRITICAL vmxnet3: disable rx data ring on dma allocation failure
CVE-2024-40983 9.8 CRITICAL tipc: force a dst refcount before doing decryption
CVE-2024-40910 8.8 HIGH ax25: Fix refcount imbalance on inbound connections
CVE-2024-40911 8.8 HIGH wifi: cfg80211: Lock wiphy in cfg80211_get_station
CVE-2024-40941 8.1 HIGH wifi: iwlwifi: mvm: don't read past the mfuart notifcation
CVE-2024-40953 7.9 HIGH KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin()
CVE-2024-40918 7.8 HIGH parisc: Try to fix random segmentation faults in package builds
CVE-2024-39495 7.8 HIGH greybus: Fix use-after-free bug in gb_interface_release due to race condition.
CVE-2024-40909 7.8 HIGH bpf: Fix a potential use-after-free in bpf_link_free()
CVE-2024-40991 7.8 HIGH dmaengine: ti: k3-udma-glue: Fix of_k3_udma_glue_parse_chn_by_id()
CVE-2024-40990 7.8 HIGH RDMA/mlx5: Add check for srq max_sge attribute
CVE-2024-40989 7.8 HIGH KVM: arm64: Disassociate vcpus from redistributor region on teardown
CVE-2024-40925 7.8 HIGH block: fix request.queuelist usage in flush
CVE-2024-40984 7.8 HIGH ACPICA: Revert "ACPICA: avoid Info: mapping multiple BARs. Your kernel is fine."
CVE-2024-40924 7.8 HIGH drm/i915/dpt: Make DPT object unshrinkable
CVE-2024-40970 7.8 HIGH Avoid hw_desc array overrun in dw-axi-dmac
CVE-2024-40943 7.8 HIGH ocfs2: fix races between hole punching and AIO+DIO

Showing top 20 of 122 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

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