btrfs: avoid potential out-of-bounds in btrfs_encode_fh()
In the Linux kernel, the following vulnerability has been resolved: btrfs: avoid potential out-of-bounds in btrfs_encode_fh() The function btrfs_encode_fh() does not properly account for the three cases it handles. Before writing to the file handle (fh), the function only returns to the user BTRFS_FID_SIZE_NON_CONNECTABLE (5 dwords, 20 bytes) or BTRFS_FID_SIZE_CONNECTABLE (8 dwords, 32 bytes). However, when a parent exists and the root ID of the parent and the inode are different, the function writes BTRFS_FID_SIZE_CONNECTABLE_ROOT (10 dwords, 40 bytes). If *max_len is not large enough, this write goes out of bounds because BTRFS_FID_SIZE_CONNECTABLE_ROOT is greater than BTRFS_FID_SIZE_CONNECTABLE originally returned. This results in an 8-byte out-of-bounds write at fid->parent_root_objectid = parent_root_id. A previous attempt to fix this issue was made but was lost. https://lore.kernel.org/all/4CADAEEC020000780001B32C@vpn.id2.novell.com/ Although this issue does not seem to be easily triggerable, it is a potential memory corruption bug that should be fixed. This patch resolves the issue by ensuring the function returns the appropriate size for all three cases and validates that *max_len is large enough before writing any data.
CVE-2025-40205
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-2025-40205
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": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "60de2f55d2aca53e81b4ef2a67d7cc9e1eb677db",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "742b44342204e5dfe3926433823623c1a0c581df",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "d3a9a8e1275eb9b87f006b5562a287aea3f6885f",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "d91f6626133698362bba08fbc04bd72c466806d3",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "0276c8582488022f057b4cec21975a5edf079f47",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "361d67276eb8ec6be8f27f4ad6c6090459438fee",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "43143776b0a7604d873d1a6f3e552a00aa930224",
"versionType": "git"
},
{
"status": "affected",
"version": "be6e8dc0ba84029997075a1ec77b4ddb863cbe15",
"lessThan": "dff4f9ff5d7f289e4545cc936362e01ed3252742",
"versionType": "git"
}
],
"programFiles": [
"fs/btrfs/export.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.29"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.29",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.4.301",
"versionType": "semver",
"lessThanOrEqual": "5.4.*"
},
{
"status": "unaffected",
"version": "5.10.246",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.195",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.157",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.113",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.54",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.17.4",
"versionType": "semver",
"lessThanOrEqual": "6.17.*"
},
{
"status": "unaffected",
"version": "6.18",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/btrfs/export.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2025-40205
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #30694 · Revision 1
- Added to Heist Feed
- Publisher date