lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 6 Jul 2020 21:21:13 +0800
From:   Stanley Chu <>
To:     <>, <>,
        <>, <>,
        <>, <>
CC:     <>, <>,
        <>, <>,
        <>, <>,
        <>, <>,
        <>, <>,
        <>, Stanley Chu <>
Subject: [PATCH v3] scsi: ufs: Cleanup completed request without interrupt notification

If somehow no interrupt notification is raised for a completed request
and its doorbell bit is cleared by host, UFS driver needs to cleanup
its outstanding bit in ufshcd_abort().

Otherwise, system may crash by below abnormal flow:

After this request is requeued by SCSI layer with its
outstanding bit set, the next completed request will trigger
ufshcd_transfer_req_compl() to handle all "completed outstanding
bits". In this time, the "abnormal outstanding bit" will be detected
and the "requeued request" will be chosen to execute request
post-processing flow. This is wrong and blk_finish_request() will
BUG_ON because this request is still "alive".

It is worth mentioning that before ufshcd_abort() cleans the timed-out
request, driver need to check again if this request is really not
handled by __ufshcd_transfer_req_compl() yet because it may be
possible that the interrupt comes very lately before the cleaning.

Signed-off-by: Stanley Chu <>
 drivers/scsi/ufs/ufshcd.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 8603b07045a6..f23fb14df9f6 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6462,7 +6462,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 			/* command completed already */
 			dev_err(hba->dev, "%s: cmd at tag %d successfully cleared from DB.\n",
 				__func__, tag);
-			goto out;
+			goto cleanup;
 		} else {
 				"%s: no response from device. tag = %d, err %d\n",
@@ -6496,9 +6496,14 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		goto out;
+	spin_lock_irqsave(host->host_lock, flags);
+	if (!test_bit(tag, &hba->outstanding_reqs)) {
+		spin_unlock_irqrestore(host->host_lock, flags);
+		goto out;
+	}
-	spin_lock_irqsave(host->host_lock, flags);
 	ufshcd_outstanding_req_clear(hba, tag);
 	hba->lrb[tag].cmd = NULL;
 	spin_unlock_irqrestore(host->host_lock, flags);

Powered by blists - more mailing lists