scsi: qla2xxx: Fix TMR failure handling

(target mode)

If handle_tmr() fails:

 - The code for QLA_TGT_ABTS results in memory-use-after-free and
   double-free:
	qlt_do_tmr_work()
		qlt_build_abts_resp_iocb()
			qpair->req->outstanding_cmds[h] = (srb_t *)mcmd;
		mempool_free(mcmd, qla_tgt_mgmt_cmd_mempool); FIRST FREE
	qlt_handle_abts_completion()
		mcmd = qlt_ctio_to_cmd()
			cmd = req->outstanding_cmds[h];
			return cmd;
		vha  = mcmd->vha; USE-AFTER-FREE
		ha->tgt.tgt_ops->free_mcmd(mcmd); SECOND FREE

 - qlt_send_busy() makes no sense because it sends a SCSI command
   response instead of a TMR response.

Instead just call qlt_xmit_tm_rsp() to send a TMR failed response, since
that code is well-tested and handles a number of corner cases.  But it
would be incorrect to call ha->tgt.tgt_ops->free_mcmd() after
handle_tmr() failed, so add a flag to mcmd indicating the proper way to
free the mcmd so that qlt_xmit_tm_rsp() can be used for both cases.

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Link: https://patch.msgid.link/09a1ff3d-6738-4953-a31b-10e89c540462@cybernetics.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Tony Battersby 2025-11-10 10:59:35 -05:00 • committed by Martin K. Petersen
commit 3d56983cc6
3 changed files with 27 additions and 33 deletions