From b761c9b1f4f69eb53fb6147547a1ab25237a93b3 Mon Sep 17 00:00:00 2001 From: Gao feng Date: Wed, 4 Jul 2012 23:28:40 +0000 Subject: cgroup: fix panic in netprio_cgroup we set max_prioidx to the first zero bit index of prioidx_map in function get_prioidx. So when we delete the low index netprio cgroup and adding a new netprio cgroup again,the max_prioidx will be set to the low index. when we set the high index cgroup's net_prio.ifpriomap,the function write_priomap will call update_netdev_tables to alloc memory which size is sizeof(struct netprio_map) + sizeof(u32) * (max_prioidx + 1), so the size of array that map->priomap point to is max_prioidx +1, which is low than what we actually need. fix this by adding check in get_prioidx,only set max_prioidx when max_prioidx low than the new prioidx. Signed-off-by: Gao feng Acked-by: Neil Horman Signed-off-by: David S. Miller --- net/core/netprio_cgroup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c index 5b8aa2fae48b..aa907ed466ea 100644 --- a/net/core/netprio_cgroup.c +++ b/net/core/netprio_cgroup.c @@ -49,8 +49,9 @@ static int get_prioidx(u32 *prio) return -ENOSPC; } set_bit(prioidx, prioidx_map); + if (atomic_read(&max_prioidx) < prioidx) + atomic_set(&max_prioidx, prioidx); spin_unlock_irqrestore(&prioidx_map_lock, flags); - atomic_set(&max_prioidx, prioidx); *prio = prioidx; return 0; } -- cgit v1.2.2