CVE-2021-47491
published 2024-05-22CVE-2021-47491: In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for filesystems…
PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
11.3th percentile
In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for filesystems will collapse THP for files opened
readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB
misses for large text segments. But it doesn't restrict the file types
so a THP could be collapsed for a non-regular file, for example, block
device, if it is opened readonly and mapped with EXEC permission. This
may cause bugs, like [1] and [2].
This is definitely not the intended usecase, so just collapse THP for
regular files in order to close the attack surface.
[[email protected]: fix vm_file check [3]]
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.15.3-1 (bookworm) | linux 5.15.3-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 99cb0dbd47a15d395bf3faa78dc122bc5efe3fc0 < 6d67b2a73b8e3a079c355bab3c1aef7d85a044b8 | 6d67b2a73b8e3a079c355bab3c1aef7d85a044b8 |
| linux | linux | >= 99cb0dbd47a15d395bf3faa78dc122bc5efe3fc0 < 5fcb6fce74ffa614d964667110cf1a516c48c6d9 | 5fcb6fce74ffa614d964667110cf1a516c48c6d9 |
| linux | linux | >= 99cb0dbd47a15d395bf3faa78dc122bc5efe3fc0 < a4aeaa06d45e90f9b279f0b09de84bd00006e733 | a4aeaa06d45e90f9b279f0b09de84bd00006e733 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.84-1 | 5.10.84-1 |
| linux | linux_kernel | >= 0 < 5.15.3-1 | 5.15.3-1 |
| linux | linux_kernel | >= 0 < 5.15.3-1 | 5.15.3-1 |
| linux | linux_kernel | >= 0 < 5.15.3-1 | 5.15.3-1 |
| linux | linux_kernel | >= 5.11 < 5.14.16 | 5.14.16 |
| linux | linux_kernel | >= 5.4 < 5.10.78 | 5.10.78 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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Red Hat
kernel: mm: khugepaged: skip huge page collapse for special files
vendor_redhat·2024-05-22·CVSS 5.5
CVE-2021-47491 [MEDIUM] CWE-664 kernel: mm: khugepaged: skip huge page collapse for special files
kernel: mm: khugepaged: skip huge page collapse for special files
In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for filesystems will collapse THP for files opened
readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB
misses for large text segments. But it doesn't restrict the file types
so a THP could be collapsed for a non-regular file, for example, block
device, if it is opened readonly and mapped with EXEC permission. This
may cause bugs, like [1] and [2].
This is definitely not the intended usecase, so just collapse THP for
regular files in order to close the attack surface.
[[email protected]: fix vm_file check [3]]
Package: kernel (Red Hat Enterprise Linux 6) - Out o
Debian
CVE-2021-47491: linux - In the Linux kernel, the following vulnerability has been resolved: mm: khugepa...
vendor_debian·2021·CVSS 5.5
CVE-2021-47491 [MEDIUM] CVE-2021-47491: linux - In the Linux kernel, the following vulnerability has been resolved: mm: khugepa...
In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2]. This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface. [[email protected]: fix vm_file check [3]]
Scope: local
bookworm: resolved (fixed in 5.15.3-1)
bullseye: resolved (fixed in 5.10.84-1)
forky: resolved (fixed in 5.
OSV
CVE-2021-47491: In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for fi
osv·2024-05-22·CVSS 5.5
CVE-2021-47491 [MEDIUM] CVE-2021-47491: In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for fi
In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2]. This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface. [[email protected]: fix vm_file check [3]]
GHSA
GHSA-8g2p-p68f-4wqr: In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for
ghsa_unreviewed·2024-05-22
CVE-2021-47491 [MEDIUM] GHSA-8g2p-p68f-4wqr: In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for
In the Linux kernel, the following vulnerability has been resolved:
mm: khugepaged: skip huge page collapse for special files
The read-only THP for filesystems will collapse THP for files opened
readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB
misses for large text segments. But it doesn't restrict the file types
so a THP could be collapsed for a non-regular file, for example, block
device, if it is opened readonly and mapped with EXEC permission. This
may cause bugs, like [1] and [2].
This is definitely not the intended usecase, so just collapse THP for
regular files in order to close the attack surface.
[[email protected]: fix vm_file check [3]]
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/5fcb6fce74ffa614d964667110cf1a516c48c6d9https://git.kernel.org/stable/c/6d67b2a73b8e3a079c355bab3c1aef7d85a044b8https://git.kernel.org/stable/c/a4aeaa06d45e90f9b279f0b09de84bd00006e733https://git.kernel.org/stable/c/5fcb6fce74ffa614d964667110cf1a516c48c6d9https://git.kernel.org/stable/c/6d67b2a73b8e3a079c355bab3c1aef7d85a044b8https://git.kernel.org/stable/c/a4aeaa06d45e90f9b279f0b09de84bd00006e733
2024-05-22
Published