Description
In the Linux kernel, the following vulnerability has been resolved:
smb: client: delete compound mids on send failure before unlock
When sending a compound request fails, smb_send_rqst() kicks off a reconnect. compound_send_recv() still has those mids on pending_mid_q, but it unlocks the server without removing them first.
During reconnect, cifs_abort_connection() walks pending_mid_q and runs each mid callback. With no response yet, those callbacks return credits and drop in_flight. Then compound_send_recv()'s send-error path returns the same credits again. in_flight ends up decremented twice and smb2_add_credits() WARNs.
syzbot hits this during SMB2_negotiate when the socket send fails.
cifs_call_async() already calls delete_mid() before unlock on send failure. Do the same for compound chains and set cancelled_mid[] so the out: path does not delete them again.
Metrics
No CVSS score has been published yet.
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
No affected versions have been published.
Timeline
- Published
- Oct 18, 2026
- Last modified
- Oct 19, 2026
- NVD status
- Received