Piteball
/
android_kernel_samsung_msm8976
mirror of https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
1
1
Fork 0
Code Issues Projects Releases Wiki Activity

libata: array underflow in ata_find_dev() 

commit 59a5e266c3f5c1567508888dd61a45b86daed0fa upstream.

My static checker complains that "devno" can be negative, meaning that
we read before the start of the loop.  I've looked at the code, and I
think the warning is right.  This come from /proc so it's root only or
it would be quite a quite a serious bug.  The call tree looks like this:

proc_scsi_write() <- gets id and channel from simple_strtoul()
-> scsi_add_single_device() <- calls shost->transportt->user_scan()
   -> ata_scsi_user_scan()
      -> ata_find_dev()

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # all versions at this point
Signed-off-by: Willy Tarreau <w@1wt.eu>
This commit is contained in:
Dan Carpenter 2017-07-19 13:06:41 +03:00 committed by syphyr
parent 71fdacd4d6
commit 6af76af715
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/ata/libata-scsi.c
View File

@ -2794,10 +2794,12 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
static struct ata_device *ata_find_dev(struct ata_port *ap, int devno)
{
if (!sata_pmp_attached(ap)) {
if (likely(devno < ata_link_max_devices(&ap->link)))
if (likely(devno >= 0 &&
devno < ata_link_max_devices(&ap->link)))
return &ap->link.device[devno];
} else {
if (likely(devno < ap->nr_pmp_links))
if (likely(devno >= 0 &&
devno < ap->nr_pmp_links))
return &ap->pmp_link[devno].device[0];
}