From: Stefan Weinhuber Date: Tue, 19 Nov 2013 13:15:57 +0000 (+0100) Subject: s390/dasd: validate request size before building CCW/TCW request X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=26a35f373fbe6f21e8ad5ca4de1c01021e38fe2f;p=linux-beck.git s390/dasd: validate request size before building CCW/TCW request An I/O request that does not read or write full blocks cannot be translated into a correct CCW or TCW program and should be rejected right away. In particular the code that creates TCW requests will not notice this problem and create broken TCWs that will be rejected by the hardware. Signed-off-by: Stefan Weinhuber Reference-ID: RQM1956 --- diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index cee7e2708a1f..95e45782692f 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -3224,6 +3224,8 @@ static struct dasd_ccw_req *dasd_eckd_build_cp(struct dasd_device *startdev, fcx_multitrack = private->features.feature[40] & 0x20; data_size = blk_rq_bytes(req); + if (data_size % blksize) + return ERR_PTR(-EINVAL); /* tpm write request add CBC data on each track boundary */ if (rq_data_dir(req) == WRITE) data_size += (last_trk - first_trk) * 4;