2.6.30-stable review patch. If anyone has any objections, please let us know. ------------------ From: Luis R. Rodriguez commit 61405e97788b1bc4e7c5be5b4ec04a73fc11bac2 upstream. There is a race on access to last_request and its alpha2 through reg_is_valid_request() and us possibly processing first another regulatory request on another CPU. We avoid this improbably race by locking with the cfg80211_mutex as we should have done in the first place. While at it add the assert on locking on reg_is_valid_request(). Signed-off-by: Luis R. Rodriguez Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- net/wireless/nl80211.c | 5 ++++- net/wireless/reg.c | 2 ++ 2 files changed, 6 insertions(+), 1 deletion(-) --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -2388,6 +2388,8 @@ static int nl80211_set_reg(struct sk_buf return -EINVAL; } + mutex_lock(&cfg80211_mutex); + if (!reg_is_valid_request(alpha2)) { r = -EINVAL; goto bad_reg; @@ -2425,13 +2427,14 @@ static int nl80211_set_reg(struct sk_buf BUG_ON(rule_idx != num_rules); - mutex_lock(&cfg80211_mutex); r = set_regdom(rd); + mutex_unlock(&cfg80211_mutex); return r; bad_reg: + mutex_unlock(&cfg80211_mutex); kfree(rd); return r; } --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -389,6 +389,8 @@ static int call_crda(const char *alpha2) /* Used by nl80211 before kmalloc'ing our regulatory domain */ bool reg_is_valid_request(const char *alpha2) { + assert_cfg80211_lock(); + if (!last_request) return false; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/