Answer in brief
CVE-2024-40949 records a Unknown severity vulnerability in mm: shmem: fix getting incorrect lruvec when replacing a shmem folio. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=85ce2c517ade0d51b7ad95f2e88be9bbe294379a <8c6c3719ebb7913f8a665d11816d2e38b0eadbab || >=85ce2c517ade0d51b7ad95f2e88be9bbe294379a <9094b4a1c76cfe84b906cc152bab34d4ba26fa5c | 8c6c3719ebb7913f8a665d11816d2e38b0eadbab, 9094b4a1c76cfe84b906cc152bab34d4ba26fa5c |
| Linux/Linuxgeneric | 6.7 | Not reported |
Published upstream
Jul 12, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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 ]--- [[email protected]: remove less helpful comments, per Matthew]
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2024-40949 records a Unknown severity vulnerability in mm: shmem: fix getting incorrect lruvec when replacing a shmem folio. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=85ce2c517ade0d51b7ad95f2e88be9bbe294379a <8c6c3719ebb7913f8a665d11816d2e38b0eadbab || >=85ce2c517ade0d51b7ad95f2e88be9bbe294379a <9094b4a1c76cfe84b906cc152bab34d4ba26fa5c | 8c6c3719ebb7913f8a665d11816d2e38b0eadbab, 9094b4a1c76cfe84b906cc152bab34d4ba26fa5c |
| Linux/Linuxgeneric | 6.7 | Not reported |
Published upstream
Jul 12, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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 ]--- [[email protected]: remove less helpful comments, per Matthew]
Quoted source text, attributed separately from HOL analysis.