CVE-2026-80980 (GCVE-0-2026-80980)
Vulnerability from cvelistv5
Published
2026-09-11 19:42
Modified
2026-10-21 12:47
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
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
Impacted products
Vendor Product Version
Linux Linux Version: b286a0651e4404ab96cdfdcdad8a839a26b3751e
Version: b286a0651e4404ab96cdfdcdad8a839a26b3751e
Version: b286a0651e4404ab96cdfdcdad8a839a26b3751e
Version: b286a0651e4404ab96cdfdcdad8a839a26b3751e
Version: b286a0651e4404ab96cdfdcdad8a839a26b3751e
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