usb: storage: return on error to avoid a null pointer dereference
authorColin Ian King <colin.king@canonical.com>
Thu, 6 Jul 2017 15:06:32 +0000 (16:06 +0100)
committerBen Hutchings <ben@decadent.org.uk>
Sat, 11 Nov 2017 13:34:23 +0000 (13:34 +0000)
commit04501c718370434109b14b5d42ad252eab687cd4
tree211623208d3d15e92941c469145f801e5e95d88a
parent9da6f42c0fd7001c00c705993776db62e2fa7820
usb: storage: return on error to avoid a null pointer dereference

commit 446230f52a5bef593554510302465eabab45a372 upstream.

When us->extra is null the driver is not initialized, however, a
later call to osd200_scsi_to_ata is made that dereferences
us->extra, causing a null pointer dereference.  The code
currently detects and reports that the driver is not initialized;
add a return to avoid the subsequent dereference issue in this
check.

Thanks to Alan Stern for pointing out that srb->result needs setting
to DID_ERROR << 16

Detected by CoverityScan, CID#100308 ("Dereference after null check")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drivers/usb/storage/isd200.c