| Message ID | 20250131152657.5606-1-v.shevtsov@mt-integration.ru (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Johannes Berg |
| Headers | show |
| Series | [v2] wifi: nl80211: reject cooked mode if it is set along with other flags | expand |
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index d7d3da0f6833..fdb2aac951d1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -4220,6 +4220,11 @@ static int parse_monitor_flags(struct nlattr *nla, u32 *mntrflags) if (flags[flag]) *mntrflags |= (1<<flag); + /* cooked monitor mode is incompatible with other modes */ + if (*mntrflags & MONITOR_FLAG_COOK_FRAMES && + *mntrflags != MONITOR_FLAG_COOK_FRAMES) + return -EOPNOTSUPP; + *mntrflags |= MONITOR_FLAG_CHANGED; return 0;
It is possible to set both MONITOR_FLAG_COOK_FRAMES and MONITOR_FLAG_ACTIVE flags simultaneously on the same monitor interface from the userspace. This causes a sub-interface to be created with no IEEE80211_SDATA_IN_DRIVER bit set because the monitor interface is in the cooked state and it takes precedence over all other states. When the interface is then being deleted the kernel calls WARN_ONCE() from check_sdata_in_driver() because of missing that bit. Fix this by rejecting MONITOR_FLAG_COOK_FRAMES if it is set along with other flags. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 66f7ac50ed7c ("nl80211: Add monitor interface configuration flags") Reported-by: syzbot+2e5c1e55b9e5c28a3da7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=2e5c1e55b9e5c28a3da7 Signed-off-by: Vitaliy Shevtsov <v.shevtsov@mt-integration.ru> --- v2: update patch name and description, reject cooked mode if the one is set along with other flags. net/wireless/nl80211.c | 5 +++++ 1 file changed, 5 insertions(+)