Don't feed anything but regular iovec's to blk_rq_map_user_iov
commit a0ac402cfcdc904f9772e1762b3fda112dcc56a0 upstream.
In theory we could map other things, but there's a reason that function
is called "user_iov". Using anything else (like splice can do) just
confuses it.
Reported-and-tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/block/blk-map.c b/block/blk-map.c
index f565e11..69953bd 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -90,6 +90,9 @@
if (!iter || !iter->count)
return -EINVAL;
+ if (!iter_is_iovec(iter))
+ return -EINVAL;
+
iov_for_each(iov, i, *iter) {
unsigned long uaddr = (unsigned long) iov.iov_base;
