CVEvulnerability
CVE-2026-80980
9.8 CRITICAL
Official page ↗
- Status
- Received
- Published
- 2026-09-11
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
net/smc: stop killed, freed and out_of_sync sharing a byte
The three connection state flags are single-bit bitfields, so they occupy
one byte of struct smc_connection and every store to one is a
read-modify-write of the other two:
u8 killed : 1;
u8 freed : 1;
u8 out_of_sync : 1;
They are not written under a common lock. smc_cdc_msg_validate() sets
out_of_sync from the receive tasklet, while smc_conn_kill() sets killed
from process context under lock_sock(), and the receive path does not defer
to the backlog when the socket is owned -- smc_cdc_msg_recv() takes only
bh_lock_sock().
Give each flag its own byte so a store no longer touches its neighbours.
All readers test them as booleans and are unchanged. struct smc_connection
grows by two bytes.
References
- https://git.kernel.org/stable/c/09a9cbadc05f452405de31012bd2c428b601291a git.kernel.org
- https://git.kernel.org/stable/c/297e96f38d3e4f1a3b84068950dd5c7a55bbdc7b git.kernel.org
- https://git.kernel.org/stable/c/2cb7a8d64b7e8ccdc69bbe48fe9c4eaa79c33aec git.kernel.org
- https://git.kernel.org/stable/c/313f79149eb337411c64e2c247234b62ef9a3cb9 git.kernel.org
- https://git.kernel.org/stable/c/db51a8658c11a82432b64999519a269c3aabb447 git.kernel.org