This is a note to let you know that I've just added the patch titled
scsi: sg: check for valid direction before starting the request
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-sg-check-for-valid-direction-before-starting-the-request.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon Mar 19 10:11:52 CET 2018
From: Johannes Thumshirn <jthumshirn@xxxxxxx>
Date: Fri, 7 Apr 2017 09:34:15 +0200
Subject: scsi: sg: check for valid direction before starting the request
From: Johannes Thumshirn <jthumshirn@xxxxxxx>
[ Upstream commit 28676d869bbb5257b5f14c0c95ad3af3a7019dd5 ]
Check for a valid direction before starting the request, otherwise we
risk running into an assertion in the scsi midlayer checking for valid
requests.
[mkp: fixed typo]
Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
Link: http://www.spinics.net/lists/linux-scsi/msg104400.html
Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Hannes Reinecke <hare@xxxxxxxx>
Tested-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/sg.c | 46 ++++++++++++++++++++++++++++++++++------------
1 file changed, 34 insertions(+), 12 deletions(-)
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -674,18 +674,14 @@ sg_write(struct file *filp, const char _
* is a non-zero input_size, so emit a warning.
*/
if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
- static char cmd[TASK_COMM_LEN];
- if (strcmp(current->comm, cmd)) {
- printk_ratelimited(KERN_WARNING
- "sg_write: data in/out %d/%d bytes "
- "for SCSI command 0x%x-- guessing "
- "data in;\n program %s not setting "
- "count and/or reply_len properly\n",
- old_hdr.reply_len - (int)SZ_SG_HEADER,
- input_size, (unsigned int) cmnd[0],
- current->comm);
- strcpy(cmd, current->comm);
- }
+ printk_ratelimited(KERN_WARNING
+ "sg_write: data in/out %d/%d bytes "
+ "for SCSI command 0x%x-- guessing "
+ "data in;\n program %s not setting "
+ "count and/or reply_len properly\n",
+ old_hdr.reply_len - (int)SZ_SG_HEADER,
+ input_size, (unsigned int) cmnd[0],
+ current->comm);
}
k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
return (k < 0) ? k : count;
@@ -764,6 +760,29 @@ sg_new_write(Sg_fd *sfp, struct file *fi
return count;
}
+static bool sg_is_valid_dxfer(sg_io_hdr_t *hp)
+{
+ switch (hp->dxfer_direction) {
+ case SG_DXFER_NONE:
+ if (hp->dxferp || hp->dxfer_len > 0)
+ return false;
+ return true;
+ case SG_DXFER_TO_DEV:
+ case SG_DXFER_FROM_DEV:
+ case SG_DXFER_TO_FROM_DEV:
+ if (!hp->dxferp || hp->dxfer_len == 0)
+ return false;
+ return true;
+ case SG_DXFER_UNKNOWN:
+ if ((!hp->dxferp && hp->dxfer_len) ||
+ (hp->dxferp && hp->dxfer_len == 0))
+ return false;
+ return true;
+ default:
+ return false;
+ }
+}
+
static int
sg_common_write(Sg_fd * sfp, Sg_request * srp,
unsigned char *cmnd, int timeout, int blocking)
@@ -784,6 +803,9 @@ sg_common_write(Sg_fd * sfp, Sg_request
"sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
(int) cmnd[0], (int) hp->cmd_len));
+ if (!sg_is_valid_dxfer(hp))
+ return -EINVAL;
+
k = sg_start_req(srp, cmnd);
if (k) {
SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
Patches currently in stable-queue which might be from jthumshirn@xxxxxxx are
queue-3.18/scsi-sg-check-for-valid-direction-before-starting-the-request.patch
queue-3.18/scsi-sg-close-race-condition-in-sg_remove_sfp_usercontext.patch