Описание
In the Linux kernel, the following vulnerability has been resolved: ocfs2: reject dinodes with non-canonical i_mode type Patch series "ocfs2: harden inode validators against forged metadata", v2. This series adds three structural checks to OCFS2 dinode validation so malformed on-disk fields are rejected before ocfs2_populate_inode() copies them into the in-core inode. The checks cover:
- i_mode values whose type bits do not name a canonical POSIX file type;
- non-device dinodes whose id1.dev1.i_rdev field is non-zero; and
- non-inline dinodes that claim non-zero i_size while i_clusters is
zero, covering directories unconditionally and regular files on
non-sparse volumes.
The normal read path reports these through ocfs2_error(), matching the
existing suballoc-slot, inline-data, chain-list, and refcount checks. The
online filecheck path uses the same structural predicates but keeps its
own reporting contract, returning OCFS2_FILECHECK_ERR_INVALIDINO instead
of calling ocfs2_error().
This patch (of 3):
ocfs2_validate_inode_block() currently accepts any non-zero i_mode value.
ocfs2_populate_inode() then copies that mode verbatim into inode->i_mode
and dispatches on i_mode & S_IFMT to the file/dir/symlink/special_file
iops; an unrecognised type falls through to ocfs2_special_file_iops and
init_special_inode().
Reject dinodes whose type bits do not name one of the seven canonical
POSIX file types. Use fs_umode_to_ftype(), the same generic file-type
conversion helper OCFS2 already uses for directory entries, so the
accepted inode type set matches the kernel file-type vocabulary instead of
open-coding a local switch.
Apply the same structural check to the online filecheck read path.
filecheck keeps its own error namespace, so it reports malformed i_mode
through the filecheck logger and OCFS2_FILECHECK_ERR_INVALIDINO instead of
calling ocfs2_error(), but it must not allow a malformed dinode to proceed
into ocfs2_populate_inode().
A flaw was found in ocfs2 (Oracle Cluster File System version 2) in the Linux kernel. This vulnerability arises from insufficient validation of on-disk inode metadata, specifically thei_modetype bits. A local attacker could exploit this by crafting a malformed disk inode with a non-canonical POSIX file type. This could bypass existing validation checks, potentially leading to unexpected system behavior or instability when the kernel processes the malformed inode.
Отчет
A moderate severity flaw was found in the Linux kernel's OCFS2 file system. The ocfs2_validate_inode_block() function accepted on-disk dinodes whose i_mode type bits did not name one of the seven canonical POSIX file types, and ocfs2_populate_inode() copied such a mode verbatim into the in-core inode, where an unrecognized type fell through to the special-file inode operations. A local attacker able to supply a crafted OCFS2 file system image, which requires local access and privileges sufficient to present such metadata, could use a malformed inode to bypass existing validation, causing unexpected system behavior or instability and a denial of service. Red Hat rated this flaw CVSS 3.1 5.5 (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) because exploitation requires local access and the impact is limited to system availability; this is lower than the upstream CVE record severity of 8.8, which assumes a network attack vector that the technical evidence does not support. All currently assessed Red Hat product streams (Red Hat Enterprise Linux 6 through 10, including kernel-rt, and Red Hat In-Vehicle OS) are recorded as not affected because the vulnerable code is not present in those shipped kernels.
Меры по смягчению последствий
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Not affected | ||
| Red Hat Enterprise Linux 6 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel | Not affected | ||
| Red Hat Enterprise Linux 8 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Not affected |
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Дополнительная информация
Статус:
EPSS
5.5 Medium
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: ocfs2: reject dinodes with non-canonical i_mode type Patch series "ocfs2: harden inode validators against forged metadata", v2. This series adds three structural checks to OCFS2 dinode validation so malformed on-disk fields are rejected before ocfs2_populate_inode() copies them into the in-core inode. The checks cover: - i_mode values whose type bits do not name a canonical POSIX file type; - non-device dinodes whose id1.dev1.i_rdev field is non-zero; and - non-inline dinodes that claim non-zero i_size while i_clusters is zero, covering directories unconditionally and regular files on non-sparse volumes. The normal read path reports these through ocfs2_error(), matching the existing suballoc-slot, inline-data, chain-list, and refcount checks. The online filecheck path uses the same structural predicates but keeps its own reporting contract, returning OCFS2_FILECHECK_ERR_INVALIDINO instead of calling ocfs2_error(). ...
In the Linux kernel, the following vulnerability has been resolved: ocfs2: reject dinodes with non-canonical i_mode type Patch series "ocfs2: harden inode validators against forged metadata", v2. This series adds three structural checks to OCFS2 dinode validation so malformed on-disk fields are rejected before ocfs2_populate_inode() copies them into the in-core inode. The checks cover: - i_mode values whose type bits do not name a canonical POSIX file type; - non-device dinodes whose id1.dev1.i_rdev field is non-zero; and - non-inline dinodes that claim non-zero i_size while i_clusters is zero, covering directories unconditionally and regular files on non-sparse volumes. The normal read path reports these through ocfs2_error(), matching the existing suballoc-slot, inline-data, chain-list, and refcount checks. The online filecheck path uses the same structural predicates but keeps its own reporting contract, returning OCFS2_FILECHECK_ERR_INVALIDINO instead of ca
In the Linux kernel, the following vulnerability has been resolved: o ...
EPSS
5.5 Medium
CVSS3