Commit 52db45c3 authored by Stefan Weinhuber's avatar Stefan Weinhuber Committed by Martin Schwidefsky
Browse files

[S390] dasd: fix idaw boundary checking for track based ccw



A ccw command that reads or writes several records at once will
usually transfer more data then fits into one page and needs to
address memory areas using a list of indirect data address words
(idaw). All but the first of these areas must start on a 4KB or 2KB
block boundary (depending on the idaw format).
A check for this restriction was missing and has been added with
this patch.
Signed-off-by: default avatarStefan Weinhuber <wein@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent f3445a1a
......@@ -2019,15 +2019,23 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_track(
ccw++;
recid += count;
new_track = 0;
/* first idaw for a ccw may start anywhere */
if (!idaw_dst)
idaw_dst = dst;
}
/* If we start a new idaw, everything is fine and the
* start of the new idaw is the start of this segment.
/* If we start a new idaw, we must make sure that it
* starts on an IDA_BLOCK_SIZE boundary.
* If we continue an idaw, we must make sure that the
* current segment begins where the so far accumulated
* idaw ends
*/
if (!idaw_dst)
idaw_dst = dst;
if (!idaw_dst) {
if (__pa(dst) & (IDA_BLOCK_SIZE-1)) {
dasd_sfree_request(cqr, startdev);
return ERR_PTR(-ERANGE);
} else
idaw_dst = dst;
}
if ((idaw_dst + idaw_len) != dst) {
dasd_sfree_request(cqr, startdev);
return ERR_PTR(-ERANGE);
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment