ocfs2: fix readdir position truncation on 32-bit kernels
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix readdir position truncation on 32-bit kernels In ocfs2_dir_foreach_blk_el(), the directory cookie position is rebuilt with ctx->pos = (ctx->pos & ~(sb->s_blocksize - 1)) | offset; `ctx->pos` is loff_t (signed 64-bit), while `sb->s_blocksize` is unsigned long. On 32-bit kernels unsigned long is 32-bit, so the mask ~(sb->s_blocksize - 1) is computed as a 32-bit unsigned value (e.g. 0xfffff000 for a 4 KiB block size). In the AND expression with the 64-bit `ctx->pos`, that unsigned operand is zero-extended to 64 bits per the usual arithmetic conversions, yielding 0x00000000fffff000. The high 32 bits of `ctx->pos` are silently cleared, even though directory size is allowed to exceed 4 GiB. When readdir() crosses the 4 GiB boundary on a 32-bit kernel the position is reset back into the first 4 GiB block, making the re-validation path re-enumerate already-returned dirents indefinitely. This is ocfs2_dir_foreach_blk_el(), the extent-list readdir path taken for all non-inline directories, so a directory large enough to cross 4 GiB reaches it. This is the same class of bug that commit 3dce5bb82c97 ("exfat: Fix bitwise operation having different size") fixed in exfat, and the fix mirrors the equivalent ext4 fix in this series. Cast the operand to loff_t so the mask is 64-bit before the AND: ctx->pos = (ctx->pos & ~((loff_t)sb->s_blocksize - 1)) | offset; 64-bit kernels are unaffected.
CVE-2026-89490
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-89490
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "c28dc3407937aa8f225942538cd585c9b28ea65a",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "94569154ba49f5f85645d2019c8e206213d8404e",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "1ae7029823ae4c91664cb32eec7fb8dd5e1a337a",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "f9dd5cad8d09110ddff2db1fe756aae93c7552ff",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "1001fb3b69a11eaa0dc7c7428f6edfa48b88997a",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "c0c165487a2ea5a37ddcdab4259157b7a527129c",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "b53e2b271eeb6040c2a4a78230c570dc41cdcfa4",
"versionType": "git"
},
{
"status": "affected",
"version": "ccd979bdbce9fba8412beb3f1de68a9d0171b12c",
"lessThan": "a63308ab426f3a3c7e33b02c150ea59054620261",
"versionType": "git"
}
],
"programFiles": [
"fs/ocfs2/dir.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.16"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.16",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/ocfs2/dir.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89490
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #35016 · Revision 1
- Added to Heist Feed
- Publisher date