This is a note to let you know that I've just added the patch titled wifi: cfg80211: wext: add extra SIOCSIWSCAN data check to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-cfg80211-wext-add-extra-siocsiwscan-data-check.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 609aa27dd3c1dc3af7b4942e6fb23ff9779521f0 Author: Dmitry Antipov <dmantipov@xxxxxxxxx> Date: Fri May 31 06:20:10 2024 +0300 wifi: cfg80211: wext: add extra SIOCSIWSCAN data check [ Upstream commit 6ef09cdc5ba0f93826c09d810c141a8d103a80fc ] In 'cfg80211_wext_siwscan()', add extra check whether number of channels passed via 'ioctl(sock, SIOCSIWSCAN, ...)' doesn't exceed IW_MAX_FREQUENCIES and reject invalid request with -EINVAL otherwise. Reported-by: syzbot+253cd2d2491df77c93ac@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=253cd2d2491df77c93ac Signed-off-by: Dmitry Antipov <dmantipov@xxxxxxxxx> Link: https://msgid.link/20240531032010.451295-1-dmantipov@xxxxxxxxx Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/wireless/scan.c b/net/wireless/scan.c index dacb9ceee3efd..0dc27703443c8 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1405,10 +1405,14 @@ int cfg80211_wext_siwscan(struct net_device *dev, wiphy = &rdev->wiphy; /* Determine number of channels, needed to allocate creq */ - if (wreq && wreq->num_channels) + if (wreq && wreq->num_channels) { + /* Passed from userspace so should be checked */ + if (unlikely(wreq->num_channels > IW_MAX_FREQUENCIES)) + return -EINVAL; n_channels = wreq->num_channels; - else + } else { n_channels = ieee80211_get_num_supported_channels(wiphy); + } creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) + n_channels * sizeof(void *),