From: Johannes Berg <johannes.berg@xxxxxxxxx> Over time, we really need to get rid of all of our global locking. One of the things needed is to use parallel_ops. This isn't really the most important (RTNL is much more important) but OTOH we just keep adding uses of genl_family_attrbuf() now. Use .parallel_ops to disallow this. Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Link: https://lore.kernel.org/r/20190726191621.5031-1-johannes@xxxxxxxxxxxxxxxx Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> --- net/wireless/nl80211.c | 108 +++++++++++++++++++++++++++++------------ 1 file changed, 78 insertions(+), 30 deletions(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index a8d4b2b6b3ec..b45d0108d2cc 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -749,17 +749,25 @@ int nl80211_prepare_wdev_dump(struct netlink_callback *cb, int err; if (!cb->args[0]) { + struct nlattr **attrbuf; + + attrbuf = kcalloc(NUM_NL80211_ATTR, sizeof(*attrbuf), + GFP_KERNEL); + if (!attrbuf) + return -ENOMEM; + err = nlmsg_parse_deprecated(cb->nlh, GENL_HDRLEN + nl80211_fam.hdrsize, - genl_family_attrbuf(&nl80211_fam), - nl80211_fam.maxattr, + attrbuf, nl80211_fam.maxattr, nl80211_policy, NULL); - if (err) + if (err) { + kfree(attrbuf); return err; + } - *wdev = __cfg80211_wdev_from_attrs( - sock_net(cb->skb->sk), - genl_family_attrbuf(&nl80211_fam)); + *wdev = __cfg80211_wdev_from_attrs(sock_net(cb->skb->sk), + attrbuf); + kfree(attrbuf); if (IS_ERR(*wdev)) return PTR_ERR(*wdev); *rdev = wiphy_to_rdev((*wdev)->wiphy); @@ -2390,14 +2398,21 @@ static int nl80211_dump_wiphy_parse(struct sk_buff *skb, struct netlink_callback *cb, struct nl80211_dump_wiphy_state *state) { - struct nlattr **tb = genl_family_attrbuf(&nl80211_fam); - int ret = nlmsg_parse_deprecated(cb->nlh, - GENL_HDRLEN + nl80211_fam.hdrsize, - tb, nl80211_fam.maxattr, - nl80211_policy, NULL); + struct nlattr **tb = kcalloc(NUM_NL80211_ATTR, sizeof(*tb), GFP_KERNEL); + int ret; + + if (!tb) + return -ENOMEM; + + ret = nlmsg_parse_deprecated(cb->nlh, + GENL_HDRLEN + nl80211_fam.hdrsize, + tb, nl80211_fam.maxattr, + nl80211_policy, NULL); /* ignore parse errors for backward compatibility */ - if (ret) - return 0; + if (ret) { + ret = 0; + goto out; + } state->split = tb[NL80211_ATTR_SPLIT_WIPHY_DUMP]; if (tb[NL80211_ATTR_WIPHY]) @@ -2410,8 +2425,10 @@ static int nl80211_dump_wiphy_parse(struct sk_buff *skb, int ifidx = nla_get_u32(tb[NL80211_ATTR_IFINDEX]); netdev = __dev_get_by_index(sock_net(skb->sk), ifidx); - if (!netdev) - return -ENODEV; + if (!netdev) { + ret = -ENODEV; + goto out; + } if (netdev->ieee80211_ptr) { rdev = wiphy_to_rdev( netdev->ieee80211_ptr->wiphy); @@ -2419,7 +2436,10 @@ static int nl80211_dump_wiphy_parse(struct sk_buff *skb, } } - return 0; + ret = 0; +out: + kfree(tb); + return ret; } static int nl80211_dump_wiphy(struct sk_buff *skb, struct netlink_callback *cb) @@ -8724,7 +8744,7 @@ static int nl80211_send_survey(struct sk_buff *msg, u32 portid, u32 seq, static int nl80211_dump_survey(struct sk_buff *skb, struct netlink_callback *cb) { - struct nlattr **attrbuf = genl_family_attrbuf(&nl80211_fam); + struct nlattr **attrbuf; struct survey_info survey; struct cfg80211_registered_device *rdev; struct wireless_dev *wdev; @@ -8732,6 +8752,10 @@ static int nl80211_dump_survey(struct sk_buff *skb, struct netlink_callback *cb) int res; bool radio_stats; + attrbuf = kcalloc(NUM_NL80211_ATTR, sizeof(*attrbuf), GFP_KERNEL); + if (!attrbuf) + return -ENOMEM; + rtnl_lock(); res = nl80211_prepare_wdev_dump(cb, &rdev, &wdev); if (res) @@ -8776,6 +8800,7 @@ static int nl80211_dump_survey(struct sk_buff *skb, struct netlink_callback *cb) cb->args[2] = survey_idx; res = skb->len; out_err: + kfree(attrbuf); rtnl_unlock(); return res; } @@ -9635,6 +9660,7 @@ static int nl80211_testmode_dump(struct sk_buff *skb, struct netlink_callback *cb) { struct cfg80211_registered_device *rdev; + struct nlattr **attrbuf = NULL; int err; long phy_idx; void *data = NULL; @@ -9655,7 +9681,12 @@ static int nl80211_testmode_dump(struct sk_buff *skb, goto out_err; } } else { - struct nlattr **attrbuf = genl_family_attrbuf(&nl80211_fam); + attrbuf = kcalloc(NUM_NL80211_ATTR, sizeof(*attrbuf), + GFP_KERNEL); + if (!attrbuf) { + err = -ENOMEM; + goto out_err; + } err = nlmsg_parse_deprecated(cb->nlh, GENL_HDRLEN + nl80211_fam.hdrsize, @@ -9722,6 +9753,7 @@ static int nl80211_testmode_dump(struct sk_buff *skb, /* see above */ cb->args[0] = phy_idx + 1; out_err: + kfree(attrbuf); rtnl_unlock(); return err; } @@ -12815,7 +12847,7 @@ static int nl80211_prepare_vendor_dump(struct sk_buff *skb, struct cfg80211_registered_device **rdev, struct wireless_dev **wdev) { - struct nlattr **attrbuf = genl_family_attrbuf(&nl80211_fam); + struct nlattr **attrbuf; u32 vid, subcmd; unsigned int i; int vcmd_idx = -1; @@ -12846,24 +12878,32 @@ static int nl80211_prepare_vendor_dump(struct sk_buff *skb, return 0; } + attrbuf = kcalloc(NUM_NL80211_ATTR, sizeof(*attrbuf), GFP_KERNEL); + if (!attrbuf) + return -ENOMEM; + err = nlmsg_parse_deprecated(cb->nlh, GENL_HDRLEN + nl80211_fam.hdrsize, attrbuf, nl80211_fam.maxattr, nl80211_policy, NULL); if (err) - return err; + goto out; if (!attrbuf[NL80211_ATTR_VENDOR_ID] || - !attrbuf[NL80211_ATTR_VENDOR_SUBCMD]) - return -EINVAL; + !attrbuf[NL80211_ATTR_VENDOR_SUBCMD]) { + err = -EINVAL; + goto out; + } *wdev = __cfg80211_wdev_from_attrs(sock_net(skb->sk), attrbuf); if (IS_ERR(*wdev)) *wdev = NULL; *rdev = __cfg80211_rdev_from_attrs(sock_net(skb->sk), attrbuf); - if (IS_ERR(*rdev)) - return PTR_ERR(*rdev); + if (IS_ERR(*rdev)) { + err = PTR_ERR(*rdev); + goto out; + } vid = nla_get_u32(attrbuf[NL80211_ATTR_VENDOR_ID]); subcmd = nla_get_u32(attrbuf[NL80211_ATTR_VENDOR_SUBCMD]); @@ -12876,15 +12916,19 @@ static int nl80211_prepare_vendor_dump(struct sk_buff *skb, if (vcmd->info.vendor_id != vid || vcmd->info.subcmd != subcmd) continue; - if (!vcmd->dumpit) - return -EOPNOTSUPP; + if (!vcmd->dumpit) { + err = -EOPNOTSUPP; + goto out; + } vcmd_idx = i; break; } - if (vcmd_idx < 0) - return -EOPNOTSUPP; + if (vcmd_idx < 0) { + err = -EOPNOTSUPP; + goto out; + } if (attrbuf[NL80211_ATTR_VENDOR_DATA]) { data = nla_data(attrbuf[NL80211_ATTR_VENDOR_DATA]); @@ -12895,7 +12939,7 @@ static int nl80211_prepare_vendor_dump(struct sk_buff *skb, attrbuf[NL80211_ATTR_VENDOR_DATA], cb->extack); if (err) - return err; + goto out; } /* 0 is the first index - add 1 to parse only once */ @@ -12907,7 +12951,10 @@ static int nl80211_prepare_vendor_dump(struct sk_buff *skb, cb->args[4] = data_len; /* keep rtnl locked in successful case */ - return 0; + err = 0; +out: + kfree(attrbuf); + return err; } static int nl80211_vendor_cmd_dump(struct sk_buff *skb, @@ -14585,6 +14632,7 @@ static struct genl_family nl80211_fam __ro_after_init = { .n_ops = ARRAY_SIZE(nl80211_ops), .mcgrps = nl80211_mcgrps, .n_mcgrps = ARRAY_SIZE(nl80211_mcgrps), + .parallel_ops = true, }; /* notification functions */ -- 2.20.1
