From: Nguyen Dinh Phi phind.uet@gmail.com

stable inclusion from stable-v4.9.291 commit 0738cdb636c21ab552eaecf905efa4a6070e3ebc category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9FNG2 CVE: CVE-2021-47194

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

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commit 563fbefed46ae4c1f70cffb8eb54c02df480b2c2 upstream.

If the userspace tools switch from NL80211_IFTYPE_P2P_GO to NL80211_IFTYPE_ADHOC via send_msg(NL80211_CMD_SET_INTERFACE), it does not call the cleanup cfg80211_stop_ap(), this leads to the initialization of in-use data. For example, this path re-init the sdata->assigned_chanctx_list while it is still an element of assigned_vifs list, and makes that linked list corrupt.

Signed-off-by: Nguyen Dinh Phi phind.uet@gmail.com Reported-by: syzbot+bbf402b783eeb6d908db@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20211027173722.777287-1-phind.uet@gmail.com Cc: stable@vger.kernel.org Fixes: ac800140c20e ("cfg80211: .stop_ap when interface is going down") Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yongqiang Liu liuyongqiang13@huawei.com --- net/wireless/util.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/net/wireless/util.c b/net/wireless/util.c index c619c82a6445..5fd7dc3ec5b0 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -913,6 +913,7 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev,

switch (otype) { case NL80211_IFTYPE_AP: + case NL80211_IFTYPE_P2P_GO: cfg80211_stop_ap(rdev, dev, true); break; case NL80211_IFTYPE_ADHOC: