4.19-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Antipov dmantipov@yandex.ru
[ 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@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=253cd2d2491df77c93ac Signed-off-by: Dmitry Antipov dmantipov@yandex.ru Link: https://msgid.link/20240531032010.451295-1-dmantipov@yandex.ru Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/wireless/scan.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
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 *),