lkml.org 
[lkml]   [2018]   [May]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] usb: storage: Fix a possible data race in uas_queuecommand_lck
Date
The write operations to "cmnd->result" and "cmnd->scsi_done" 
are protected by the lock on line 642-643, but the write operations
to these data on line 634-635 are not protected by the lock.
Thus, there may exist a data race for "cmnd->result"
and "cmnd->scsi_done".

To fix this data race, the write operations on line 634-635
should be also protected by the lock.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
drivers/usb/storage/uas.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 6034c39b67d1..dde7a43ad491 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -627,17 +627,18 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
if (cmnd->device->host->host_self_blocked)
return SCSI_MLQUEUE_DEVICE_BUSY;

+ spin_lock_irqsave(&devinfo->lock, flags);
+
if ((devinfo->flags & US_FL_NO_ATA_1X) &&
(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
sizeof(usb_stor_sense_invalidCDB));
cmnd->result = SAM_STAT_CHECK_CONDITION;
cmnd->scsi_done(cmnd);
+ spin_unlock_irqrestore(&devinfo->lock, flags);
return 0;
}

- spin_lock_irqsave(&devinfo->lock, flags);
-
if (devinfo->resetting) {
cmnd->result = DID_ERROR << 16;
cmnd->scsi_done(cmnd);
--
2.17.0
\
 
 \ /
  Last update: 2018-05-08 09:48    [W:0.034 / U:0.188 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site