batman-adv: bla: avoid CRC corruption due to parallel claim add
In the Linux kernel, the following vulnerability has been resolved: batman-adv: bla: avoid CRC corruption due to parallel claim add batadv_bla_add_claim() is used to add claims and modify the backbone of claims for CLAIM frames from remote backbones and local packets. When it handles a claim, it needs to either * add the new claim's CRC to the backbone CRC * remove the already existing claim's CRC from the old backbone and add it to the new backbone But when the "new" claim code was running in parallel to the "change backbone" code, it can happen that the CRC was invalid because the backbone_gw of the claim was changed twice in the "new" claim code path: * CPU0 creates the claim for gateway A and publishes it in the claim hash. The crc16 of the address has not yet been added to A's crc at this point. * CPU1 processes a claim frame of gateway B for the same client, finds the just published claim, and performs the ownership change: it switches the pointer to B, removes the crc16 from A's crc - which never contained it - and adds it to B's crc. * CPU0 continues behind the creation branch, unconditionally switches the pointer back to A without compensating B's crc (its remove_crc is false for the creation path), and finally adds the crc16 to A's crc The CRC is then wrong for both: * claim belongs to A: but CRC is not part of backbone A's CRC * claim doesn't belong to B: CRC is still part of backbone B's CRC This wrong CRC is never recomputated from the stored claims. For local ba
CVE-2026-93203
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-2026-93203
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": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "3d4a9ae2c69c0fe4c3c69587288241243bb7a39b",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "ad982d925f00d860d2467811256ffadcccd9e4a7",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "d5b0e7574da5a485f4dbec32a15911900a4487c2",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "a3e07db74f22a85aeeb51c600da5c98b9cbca11f",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "1d390db003cbb52cdd86837608bff3794501a5ea",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "8bcfa58c4277bff1882a23547c37ab08aa1de12f",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "e54602d9e38db8573f2097d60c7ea8be0a5af1fa",
"versionType": "git"
},
{
"status": "affected",
"version": "23721387c409087fd3b97e274f34d3ddc0970b74",
"lessThan": "08645ab95768b88e2ff85a89211994651710465b",
"versionType": "git"
}
],
"programFiles": [
"net/batman-adv/bridge_loop_avoidance.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.5"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.5",
"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": "6.12.110",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/batman-adv/bridge_loop_avoidance.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-93203
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #37907 · Revision 1
- Added to Heist Feed
- Publisher date