crush: fix a bug in tree bucket decode
authorIlya Dryomov <idryomov@gmail.com>
Mon, 29 Jun 2015 16:30:23 +0000 (19:30 +0300)
committerIlya Dryomov <idryomov@gmail.com>
Tue, 30 Jun 2015 21:46:35 +0000 (00:46 +0300)
commit82cd003a77173c91b9acad8033fb7931dac8d751
tree8c5f6e866c107968ebfdc95e7de8fba62b76d89e
parentc2cfa19400979dc1a14bba75f83b451b0cd9507a
crush: fix a bug in tree bucket decode

struct crush_bucket_tree::num_nodes is u8, so ceph_decode_8_safe()
should be used.  -Wconversion catches this, but I guess it went
unnoticed in all the noise it spews.  The actual problem (at least for
common crushmaps) isn't the u32 -> u8 truncation though - it's the
advancement by 4 bytes instead of 1 in the crushmap buffer.

Fixes: http://tracker.ceph.com/issues/2759

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
net/ceph/osdmap.c