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 ]---
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CVSS Details
- CVSS 3.1 Base Score: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade linux | Jul 27, 2026 | Jul 27, 2026 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Jul 12, 2024 |
| Ubuntu | — | Upgrade linux-image-kvmUpgrade linux-image-generic-lpaeUpgrade linux-image-nvidia-64k-6.8Upgrade linux-image-gkeUpgrade linux-image-gcpUpgrade linux-image-6.8.0-1010-gkeUpgrade linux-image-generic-64k-hwe-22.04Upgrade linux-image-6.8.0-1012-oracleUpgrade linux-image-nvidia-lowlatency-64kUpgrade linux-image-6.8.0-1011-raspiUpgrade linux-image-6.8.0-1012-ibmUpgrade linux-image-6.8.0-1012-oracle-64kUpgrade linux-image-6.8.0-1013-nvidia-lowlatency-64kUpgrade linux-image-oracleUpgrade linux-image-virtualUpgrade linux-image-lowlatency-hwe-22.04Upgrade linux-image-virtual-hwe-24.04Upgrade linux-image-6.8.0-44-lowlatencyUpgrade linux-image-lowlatency-64k-hwe-22.04Upgrade linux-image-6.8.0-1014-azureUpgrade linux-image-oem-22.04dUpgrade linux-image-generic-64k-hwe-24.04Upgrade linux-image-awsUpgrade linux-image-6.8.0-1013-nvidia-lowlatencyUpgrade linux-image-6.8.0-44-lowlatency-64kUpgrade linux-image-6.8.0-44-genericUpgrade linux-image-6.8.0-45-genericUpgrade linux-image-lowlatencyUpgrade linux-image-raspiUpgrade linux-image-nvidia-lowlatencyUpgrade linux-image-6.8.0-45-generic-64kUpgrade linux-image-generic-hwe-22.04Upgrade linux-image-oem-22.04Upgrade linux-image-6.8.0-1013-nvidiaUpgrade linux-image-ibm-classicUpgrade linux-image-6.8.0-1014-azure-fdeUpgrade linux-image-6.8.0-1015-awsUpgrade linux-image-lowlatency-64kUpgrade linux-image-nvidiaUpgrade linux-image-oem-22.04bUpgrade linux-image-generic-64kUpgrade linux-image-6.8.0-1012-oemUpgrade linux-image-6.8.0-1013-nvidia-64kUpgrade linux-image-azureUpgrade linux-image-oem-22.04aUpgrade linux-image-virtual-hwe-22.04Upgrade linux-image-oem-22.04cUpgrade linux-image-genericUpgrade linux-image-ibmUpgrade linux-image-generic-hwe-24.04Upgrade linux-image-6.8.0-44-generic-64kUpgrade linux-image-nvidia-6.8Upgrade linux-image-nvidia-64kUpgrade linux-image-oracle-64kUpgrade linux-image-ibm-lts-24.04Upgrade linux-image-azure-fdeUpgrade linux-image-6.8.0-1014-gcp | Sep 12, 2024 | Jul 12, 2024 |
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