scsi: qla2xxx: Avoid double completion in async IOCB timeout
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.8epss 0.7%
exploitation probability
0.7%top 49% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Avoid double completion in async IOCB timeout
qla2x00_async_iocb_timeout() tries to abort a timed-out async IOCB. When
qla24xx_async_abort_cmd() fails, both the SRB_LOGIN_CMD path and the
SRB_CTRL_VP/default path scan outstanding_cmds[] for the SRB and then
call sp->done(sp, QLA_FUNCTION_TIMEOUT) unconditionally, without checking
whether the SRB was actually found and removed.
If the response ISR completes the same handle first, it removes the SRB
under qp_lock_ptr and runs sp->done() -> complete(sp->comp). The
submitter qla24xx_control_vp() wakes from wait_for_completion(), clears
sp->comp, drops its reference and returns, reclaiming the on-stack
completion. The timer reference keeps the SRB alive across the timeout
handler, but not the submitter's stack. The timeout then issues a second
sp->done() -> qla_ctrlvp_sp_done(), which evaluates "if (sp->comp)
complete(sp->comp)"; with the pointer loaded before the submitter's NULL
store, complete() writes into the freed stack frame, a use-after-free.
Track whether this path removed the SRB from outstanding_cmds and only
call sp->done() when it did, so the command is completed exactly once by
whichever path owns it. This mirrors the sp_found guard already used in
qla24xx_abort_iocb_timeout().
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Linux · LinuxReferences
https://git.kernel.org/stable/c/6e217a9482eabbd8b29847be334c74cf468d3544https://git.kernel.org/stable/c/71a7b6e3c7f121439f51a058e53d4a8e05b63dechttps://git.kernel.org/stable/c/7257b5e1fb6c9387714f66e01b79ec82b717eedehttps://git.kernel.org/stable/c/845d4abd92cd2f97551356c8b281ad6e197acb07https://git.kernel.org/stable/c/9fa1d71233a82416492d9c9de9756ebe140fe714https://git.kernel.org/stable/c/bb45bc4bd53c95a7bf6f782577b5ede94c0f8aa8https://git.kernel.org/stable/c/d6d856c722f40f0694ff755208552e658db6dd42https://git.kernel.org/stable/c/f5b660e0b0d9190d8853c795c2522cc5f8c93003