diff options
| author | Javier Cardona <javier@cozybit.com> | 2011-05-03 16:57:15 -0700 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2011-05-11 14:50:30 -0400 |
| commit | 9ca99eeca0cfe839c481f3350988e9ed94188567 (patch) | |
| tree | 941425d359c2b43a2a2009155f69f0008306ab2c | |
| parent | 8f9cb77d6d213c153b0571f494df0c24456aaf47 (diff) | |
mac80211: Check size of a new mesh path table for changes since allocation.
Not sure if I'm chasing a ghost here, seems like the
mesh_path->size_order needs to be inside an RCU-read section to prevent
that value from changing between table allocation and copying. We have
observed crashes that might be caused by this.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | net/mac80211/mesh_pathtbl.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c index 7776ae5a8f1..c1a2bf2aa2d 100644 --- a/net/mac80211/mesh_pathtbl.c +++ b/net/mac80211/mesh_pathtbl.c @@ -76,7 +76,6 @@ static int mesh_table_grow(struct mesh_table *oldtbl, < oldtbl->mean_chain_len * (oldtbl->hash_mask + 1)) return -EAGAIN; - newtbl->free_node = oldtbl->free_node; newtbl->mean_chain_len = oldtbl->mean_chain_len; newtbl->copy_node = oldtbl->copy_node; @@ -329,7 +328,8 @@ void mesh_mpath_table_grow(void) { struct mesh_table *oldtbl, *newtbl; - newtbl = mesh_table_alloc(mesh_paths->size_order + 1); + rcu_read_lock(); + newtbl = mesh_table_alloc(rcu_dereference(mesh_paths)->size_order + 1); if (!newtbl) return; write_lock(&pathtbl_resize_lock); @@ -339,6 +339,7 @@ void mesh_mpath_table_grow(void) write_unlock(&pathtbl_resize_lock); return; } + rcu_read_unlock(); rcu_assign_pointer(mesh_paths, newtbl); write_unlock(&pathtbl_resize_lock); @@ -350,7 +351,8 @@ void mesh_mpp_table_grow(void) { struct mesh_table *oldtbl, *newtbl; - newtbl = mesh_table_alloc(mpp_paths->size_order + 1); + rcu_read_lock(); + newtbl = mesh_table_alloc(rcu_dereference(mpp_paths)->size_order + 1); if (!newtbl) return; write_lock(&pathtbl_resize_lock); @@ -360,6 +362,7 @@ void mesh_mpp_table_grow(void) write_unlock(&pathtbl_resize_lock); return; } + rcu_read_unlock(); rcu_assign_pointer(mpp_paths, newtbl); write_unlock(&pathtbl_resize_lock); |