From 0ec1d15ec6ed513ab2cc86c67d94761d71228a32 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Wed, 5 Feb 2014 15:19:55 +0200 Subject: [PATCH] libceph: do not dereference a NULL bio pointer Commit f38a5181d9f3 ("ceph: Convert to immutable biovecs") introduced a NULL pointer dereference, which broke rbd in -rc1. Fix it. Cc: Kent Overstreet Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil --- net/ceph/messenger.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 0e478a0f420..30efc5c1862 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -840,9 +840,13 @@ static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor, if (!cursor->bvec_iter.bi_size) { bio = bio->bi_next; - cursor->bvec_iter = bio->bi_iter; + cursor->bio = bio; + if (bio) + cursor->bvec_iter = bio->bi_iter; + else + memset(&cursor->bvec_iter, 0, + sizeof(cursor->bvec_iter)); } - cursor->bio = bio; if (!cursor->last_piece) { BUG_ON(!cursor->resid); -- 2.43.2