can: isotp: serialize TX state transitions under so->rx_lock
In the Linux kernel, the following vulnerability has been resolved: can: isotp: serialize TX state transitions under so->rx_lock The TX state machine (so->tx.state) is driven from three contexts: sendmsg() claiming and progressing a transfer, the RX path consuming Flow Control/echo frames, and two hrtimers timing out a stalled transfer. Mixing a lock-free cmpxchg() claim in sendmsg() with hrtimer_cancel() calls made under so->rx_lock elsewhere left windows where a frame or timer callback could act on a state that had already moved on, corrupting an unrelated transfer. so->rx_lock now covers the full lifecycle of a TX claim: sendmsg() takes it to check so->tx.state is ISOTP_IDLE, switch it to ISOTP_SENDING, bump so->tx_gen and drain the previous transfer's timers - all as one critical section. isotp_rcv_fc()/isotp_rcv_cf() already run under this lock via isotp_rcv(), and isotp_rcv_echo() now takes it itself, so none of them can ever observe a transfer mid-claim. This also means a transfer can no longer be handed to sendmsg()'s cleanup paths (signal or send error) while another thread is concurrently claiming or finishing it, so those paths can cancel timers and reset the state unconditionally. isotp_release() claims the socket the same way, so a racing sendmsg() sees a consistent ISOTP_SHUTDOWN and skips arming its timer or sending. Only the hrtimer callbacks stay outside so->rx_lock, since they run under so->rx_lock's cancellation elsewhere and taking it themselves would dead
CVE-2026-72124
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-2026-72124
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": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "bbedeb67a9a684f2fb78c55bd3662c400526715e",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "377a8f500704da42ed86a4541ed930e9dcfdb2ea",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "6da8119e8dd542194103139812d1a4b7dcd1aedd",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "0b05eca9589f609e2491b528dccf683168a4cda8",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "a7d90e7b5e75d7406c889fe36e9a61ee364a00cb",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "37beb16e08cae94cc05840c7274225e3b0b38ae7",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "4f1fdf1a1c317bcac0c6b6c8e12642c9983de1ca",
"versionType": "git"
},
{
"status": "affected",
"version": "e057dd3fc20ffb3d7f150af46542a51b59b90127",
"lessThan": "cf070fe33bfbd1a4c21236078fadb35dd223a157",
"versionType": "git"
}
],
"programFiles": [
"net/can/isotp.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.10"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.10",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.265",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.216",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.183",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.148",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.101",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/can/isotp.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-72124
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #32951 · Revision 1
- Added to Heist Feed
- Publisher date