On 10/13/21 8:01 AM, Adrian Hunter wrote:
__ufshcd_issue_tm_cmd() clears req->end_io_data after timing out,
which races with the completion function ufshcd_tmc_handler() which
expects req->end_io_data to have a value.
Note __ufshcd_issue_tm_cmd() and ufshcd_tmc_handler() are already
synchronized using hba->tmf_rqs and hba->outstanding_tasks under the
host_lock spinlock.
It is also not necessary (nor typical) to clear req->end_io_data because
the block layer does it before allocating out requests e.g. via
blk_get_request().
So fix by not clearing it.
Fixes: f5ef336fd2e4c3 ("scsi: ufs: core: Fix task management completion")
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 5 -----
1 file changed, 5 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 95be7ecdfe10..f34b3994d1aa 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6550,11 +6550,6 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba,
err = wait_for_completion_io_timeout(&wait,
msecs_to_jiffies(TM_CMD_TIMEOUT));
if (!err) {
- /*
- * Make sure that ufshcd_compl_tm() does not trigger a
- * use-after-free.
- */
- req->end_io_data = NULL;
ufshcd_add_tm_upiu_trace(hba, task_tag, UFS_TM_ERR);
dev_err(hba->dev, "%s: task management cmd 0x%.2x timed-out\n",
__func__, tm_function);
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
