In the Linux kernel, the following vulnerability has been resolved:
can: isotp: fix timer drain order, wakeup handling and tx_gen ordering
This patch is a follow-up to commit cf070fe33bfb ("can: isotp: serialize
TX state transitions under so->rx_lock") which addresses following
sashiko-bot findings:
- isotp_sendmsg(): drain so->txfrtimer first so a stale callback can't
re-arm echotimer after the claim
- isotp_release(): wake so->wait after forcing ISOTP_SHUTDOWN so a
sleeping sendmsg() claim isn't stranded
- isotp_sendmsg(): have both wait_event_interruptible() calls in
isotp_sendmsg() also wake on ISOTP_SHUTDOWN and do not return claim to
IDLE to avoid corrupting a concurrent isotp_release() process.
- isotp_sendmsg(): handle potential claim of a new transfer when
the wait_event_interruptible() call returns in CAN_ISOTP_WAIT_TX_DONE
mode. Don't touch timers and states of the new transfer if a new thread
incremented so->tx_gen before getting the lock at err_event_drop.
- isotp_sendmsg(): handle a stuck can_send() and omit timer and state
changes if a new transfer was claimed. wait_tx_done() returns the error
recorded in so->tx_result[], tagged with the caller's own generation.
- isotp_tx_timeout(): on a claimed timeout, record the ECOMM error for
the timed-out transfer's own generation in so->tx_result[]; sk->sk_err
is raised unconditionally, same as every other error path here.
- isotp_tx_gen_done()/isotp_tx_timeout(): always read tx.state (acquire)
before tx_gen - the reverse order let a weakly ordered CPU pair a fresh
tx.state with a stale tx_gen/tx_result slot.
- isotp_sendmsg(): wait_tx_done: drain sk_err via sock_error() once we
have read the result from so->tx_result[], so an already-reported error
doesn't stay latched for a later poll()/SO_ERROR.
Also align the remaining lock-free so->tx.state/rx.state/cfecho accesses
and use skb->hash as unique loopback echo frame indicator.
can: isotp: fix timer drain order, wakeup handling and tx_gen ordering
This patch is a follow-up to commit cf070fe33bfb ("can: isotp: serialize
TX state transitions under so->rx_lock") which addresses following
sashiko-bot findings:
- isotp_sendmsg(): drain so->txfrtimer first so a stale callback can't
re-arm echotimer after the claim
- isotp_release(): wake so->wait after forcing ISOTP_SHUTDOWN so a
sleeping sendmsg() claim isn't stranded
- isotp_sendmsg(): have both wait_event_interruptible() calls in
isotp_sendmsg() also wake on ISOTP_SHUTDOWN and do not return claim to
IDLE to avoid corrupting a concurrent isotp_release() process.
- isotp_sendmsg(): handle potential claim of a new transfer when
the wait_event_interruptible() call returns in CAN_ISOTP_WAIT_TX_DONE
mode. Don't touch timers and states of the new transfer if a new thread
incremented so->tx_gen before getting the lock at err_event_drop.
- isotp_sendmsg(): handle a stuck can_send() and omit timer and state
changes if a new transfer was claimed. wait_tx_done() returns the error
recorded in so->tx_result[], tagged with the caller's own generation.
- isotp_tx_timeout(): on a claimed timeout, record the ECOMM error for
the timed-out transfer's own generation in so->tx_result[]; sk->sk_err
is raised unconditionally, same as every other error path here.
- isotp_tx_gen_done()/isotp_tx_timeout(): always read tx.state (acquire)
before tx_gen - the reverse order let a weakly ordered CPU pair a fresh
tx.state with a stale tx_gen/tx_result slot.
- isotp_sendmsg(): wait_tx_done: drain sk_err via sock_error() once we
have read the result from so->tx_result[], so an already-reported error
doesn't stay latched for a later poll()/SO_ERROR.
Also align the remaining lock-free so->tx.state/rx.state/cfecho accesses
and use skb->hash as unique loopback echo frame indicator.
Metrics
Affected Vendors & Products
No data.
No data.
OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.
No data.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 04 Sep 2026 20:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-362 |
Fri, 04 Sep 2026 17:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: can: isotp: fix timer drain order, wakeup handling and tx_gen ordering This patch is a follow-up to commit cf070fe33bfb ("can: isotp: serialize TX state transitions under so->rx_lock") which addresses following sashiko-bot findings: - isotp_sendmsg(): drain so->txfrtimer first so a stale callback can't re-arm echotimer after the claim - isotp_release(): wake so->wait after forcing ISOTP_SHUTDOWN so a sleeping sendmsg() claim isn't stranded - isotp_sendmsg(): have both wait_event_interruptible() calls in isotp_sendmsg() also wake on ISOTP_SHUTDOWN and do not return claim to IDLE to avoid corrupting a concurrent isotp_release() process. - isotp_sendmsg(): handle potential claim of a new transfer when the wait_event_interruptible() call returns in CAN_ISOTP_WAIT_TX_DONE mode. Don't touch timers and states of the new transfer if a new thread incremented so->tx_gen before getting the lock at err_event_drop. - isotp_sendmsg(): handle a stuck can_send() and omit timer and state changes if a new transfer was claimed. wait_tx_done() returns the error recorded in so->tx_result[], tagged with the caller's own generation. - isotp_tx_timeout(): on a claimed timeout, record the ECOMM error for the timed-out transfer's own generation in so->tx_result[]; sk->sk_err is raised unconditionally, same as every other error path here. - isotp_tx_gen_done()/isotp_tx_timeout(): always read tx.state (acquire) before tx_gen - the reverse order let a weakly ordered CPU pair a fresh tx.state with a stale tx_gen/tx_result slot. - isotp_sendmsg(): wait_tx_done: drain sk_err via sock_error() once we have read the result from so->tx_result[], so an already-reported error doesn't stay latched for a later poll()/SO_ERROR. Also align the remaining lock-free so->tx.state/rx.state/cfecho accesses and use skb->hash as unique loopback echo frame indicator. | |
| Title | can: isotp: fix timer drain order, wakeup handling and tx_gen ordering | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-04T17:11:05.854Z
Reserved: 2026-08-26T14:34:25.799Z
Link: CVE-2026-80889
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-04T18:17:56.910
Modified: 2026-09-04T18:17:56.910
Link: CVE-2026-80889
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-09-04T20:30:16Z
Weaknesses