From: Gao feng Date: Wed, 11 Jul 2012 21:50:15 +0000 (+0000) Subject: net: cgroup: fix access the unallocated memory in netprio cgroup X-Git-Tag: v3.5~24^2~6 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ef209f15980360f6945873df3cd710c5f62f2a3e;p=pandora-kernel.git net: cgroup: fix access the unallocated memory in netprio cgroup there are some out of bound accesses in netprio cgroup. now before accessing the dev->priomap.priomap array,we only check if the dev->priomap exist.and because we don't want to see additional bound checkings in fast path, so we should make sure that dev->priomap is null or array size of dev->priomap.priomap is equal to max_prioidx + 1; so in write_priomap logic,we should call extend_netdev_table when dev->priomap is null and dev->priomap.priomap_len < max_len. and in cgrp_create->update_netdev_tables logic,we should call extend_netdev_table only when dev->priomap exist and dev->priomap.priomap_len < max_len. and it's not needed to call update_netdev_tables in write_priomap, we can only allocate the net device's priomap which we change through net_prio.ifpriomap. this patch also add a return value for update_netdev_tables & extend_netdev_table, so when new_priomap is allocated failed, write_priomap will stop to access the priomap,and return -ENOMEM back to the userspace to tell the user what happend. Change From v3: 1. add rtnl protect when reading max_prioidx in write_priomap. 2. only call extend_netdev_table when map->priomap_len < max_len, this will make sure array size of dev->map->priomap always bigger than any prioidx. 3. add a function write_update_netdev_table to make codes clear. Change From v2: 1. protect extend_netdev_table by RTNL. 2. when extend_netdev_table failed,call dev_put to reduce device's refcount. Signed-off-by: Gao feng Cc: Neil Horman Cc: Eric Dumazet Acked-by: Neil Horman Signed-off-by: David S. Miller --- Reading git-diff-tree failed