path: root/net
diff options
authorJay Vosburgh <fubar@us.ibm.com>2013-05-31 11:57:28 +0000
committerDavid S. Miller <davem@davemloft.net>2013-05-31 16:56:56 -0700
commit29ca2f8fcc721517b83d0a560c47cee2dde827a6 (patch)
treebbd07f503392c4d59b61f99faaf886118a2558fd /net
parent60ba834c2fb65f2fafee47e03c258fac579d0591 (diff)
net/core: __hw_addr_sync_one / _multiple broken
Currently, __hw_addr_sync_one is called in a loop by __hw_addr_sync_multiple to sync each of a "from" device's hw addresses to a "to" device. __hw_addr_sync_one calls __hw_addr_add_ex to attempt to add each address. __hw_addr_add_ex is called with global=false, and sync=true. __hw_addr_add_ex checks to see if the new address matches an address already on the list. If so, it tests global and sync. In this case, sync=true, and it then checks if the address is already synced, and if so, returns 0. This 0 return causes __hw_addr_sync_one to increment the sync_cnt and refcount for the "from" list's address entry, even though the address is already synced and has a reference and sync_cnt. This will cause the sync_cnt and refcount to increment without bound every time an addresses is added to the "from" device and synced to the "to" device. The fix here has two parts: First, when __hw_addr_add_ex finds the address already exists and is synced, return -EEXIST instead of 0. Second, __hw_addr_sync_one checks the error return for -EEXIST, and if so, it (a) does not add a refcount/sync_cnt, and (b) returns 0 itself so that __hw_addr_sync_multiple will not return an error. Signed-off-by: Jay Vosburgh <fubar@us.ibm.com> Reviewed-by: Vlad Yasevich <vyasevic@redhat.com> Tested-by: Shawn Bohrer <sbohrer@rgmadvisors.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
1 files changed, 7 insertions, 4 deletions
diff --git a/net/core/dev_addr_lists.c b/net/core/dev_addr_lists.c
index c858e81e6423..8e2c2ef8053d 100644
--- a/net/core/dev_addr_lists.c
+++ b/net/core/dev_addr_lists.c
@@ -67,7 +67,7 @@ static int __hw_addr_add_ex(struct netdev_hw_addr_list *list,
if (sync) {
if (ha->synced)
- return 0;
+ return -EEXIST;
ha->synced = true;
@@ -140,10 +140,13 @@ static int __hw_addr_sync_one(struct netdev_hw_addr_list *to_list,
err = __hw_addr_add_ex(to_list, ha->addr, addr_len, ha->type,
false, true);
- if (err)
+ if (err && err != -EEXIST)
return err;
- ha->sync_cnt++;
- ha->refcount++;
+ if (!err) {
+ ha->sync_cnt++;
+ ha->refcount++;
+ }
return 0;

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