On Sun, Aug 14, 2022 at 08:45:12PM +0530, Siddh Raman Pant via Linux-kernel-mentees wrote: > When we are not connected to a channel, sending channel "switch" > announcement doesn't make any sense. > > The BSS list is empty in that case. This causes the for loop in > cfg80211_get_bss() to be bypassed, so the function returns NULL > (check line 1424 of net/wireless/scan.c), causing the WARN_ON() > in ieee80211_ibss_csa_beacon() to get triggered (check line 500 > of net/mac80211/ibss.c), which was consequently reported on the > syzkaller dashboard. > > Thus, check if we have an existing connection before generating > the CSA beacon in ieee80211_ibss_finish_csa(). > > Fixes: cd7760e62c2a ("mac80211: add support for CSA in IBSS mode") > Bug report: https://syzkaller.appspot.com/bug?id=05603ef4ae8926761b678d2939a3b2ad28ab9ca6 > Reported-by: syzbot+b6c9fe29aefe68e4ad34@xxxxxxxxxxxxxxxxxxxxxxxxx > Cc: stable@xxxxxxxxxxxxxxx > > Signed-off-by: Siddh Raman Pant <code@xxxxxxxx> Please no blank line before your signed-off-by line or the tools will not like it. And did sysbot verify that this change solved the problem? thanks, greg k-h