scsi: sg: don't return bogus Sg_requests

If the list search in sg_get_rq_mark() fails to find a valid request, we
return a bogus element. This then can later lead to a GPF in
sg_remove_scat().

So don't return bogus Sg_requests in sg_get_rq_mark() but NULL in case
the list search doesn't find a valid request.

Signed-off-by: Johannes Thumshirn <[email protected]>
Reported-by: Andrey Konovalov <[email protected]>
Cc: Hannes Reinecke <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Doug Gilbert <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Acked-by: Doug Gilbert <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
This commit is contained in:
Johannes Thumshirn 2017-05-10 09:53:40 +02:00 • committed by Martin K. Petersen
commit 48ae8484e9

View file

@ -2074,11 +2074,12 @@ sg_get_rq_mark(Sg_fd * sfp, int pack_id)
if ((1 == resp->done) && (!resp->sg_io_owned) &&
((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
resp->done = 2; /* guard against other readers */
break;
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return resp;
}
}
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return resp;
return NULL;
}
/* always adds to end of list */