diff options
Diffstat (limited to 'net/wireless/nl80211.c')
| -rw-r--r-- | net/wireless/nl80211.c | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 7a7b621d45f..d44ab216c0e 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -1307,7 +1307,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 portid, u32 seq, int flag static int nl80211_dump_wiphy(struct sk_buff *skb, struct netlink_callback *cb) { - int idx = 0; + int idx = 0, ret; int start = cb->args[0]; struct cfg80211_registered_device *dev; @@ -1317,9 +1317,29 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, struct netlink_callback *cb) continue; if (++idx <= start) continue; - if (nl80211_send_wiphy(skb, NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, NLM_F_MULTI, - dev) < 0) { + ret = nl80211_send_wiphy(skb, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + dev); + if (ret < 0) { + /* + * If sending the wiphy data didn't fit (ENOBUFS or + * EMSGSIZE returned), this SKB is still empty (so + * it's not too big because another wiphy dataset is + * already in the skb) and we've not tried to adjust + * the dump allocation yet ... then adjust the alloc + * size to be bigger, and return 1 but with the empty + * skb. This results in an empty message being RX'ed + * in userspace, but that is ignored. + * + * We can then retry with the larger buffer. + */ + if ((ret == -ENOBUFS || ret == -EMSGSIZE) && + !skb->len && + cb->min_dump_alloc < 4096) { + cb->min_dump_alloc = 4096; + mutex_unlock(&cfg80211_mutex); + return 1; + } idx--; break; } @@ -1336,7 +1356,7 @@ static int nl80211_get_wiphy(struct sk_buff *skb, struct genl_info *info) struct sk_buff *msg; struct cfg80211_registered_device *dev = info->user_ptr[0]; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + msg = nlmsg_new(4096, GFP_KERNEL); if (!msg) return -ENOMEM; |