Takashi Iwai <tiwai@xxxxxxx> writes: > On Wed, 15 Jun 2022 11:05:20 +0200, > Toke Høiland-Jørgensen wrote: > >> >> Kalle Valo <kvalo@xxxxxxxxxx> writes: >> >> > Toke Høiland-Jørgensen <toke@xxxxxxx> writes: >> > >> >> Pavel Skripkin <paskripkin@xxxxxxxxx> writes: >> >> >> >>> Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb() [0]. The >> >>> problem was in incorrect htc_handle->drv_priv initialization. >> >>> >> >>> Probable call trace which can trigger use-after-free: >> >>> >> >>> ath9k_htc_probe_device() >> >>> /* htc_handle->drv_priv = priv; */ >> >>> ath9k_htc_wait_for_target() <--- Failed >> >>> ieee80211_free_hw() <--- priv pointer is freed >> >>> >> >>> <IRQ> >> >>> ... >> >>> ath9k_hif_usb_rx_cb() >> >>> ath9k_hif_usb_rx_stream() >> >>> RX_STAT_INC() <--- htc_handle->drv_priv access >> >>> >> >>> In order to not add fancy protection for drv_priv we can move >> >>> htc_handle->drv_priv initialization at the end of the >> >>> ath9k_htc_probe_device() and add helper macro to make >> >>> all *_STAT_* macros NULL safe, since syzbot has reported related NULL >> >>> deref in that macros [1] >> >>> >> >>> Link: https://syzkaller.appspot.com/bug?id=6ead44e37afb6866ac0c7dd121b4ce07cb665f60 [0] >> >>> Link: https://syzkaller.appspot.com/bug?id=b8101ffcec107c0567a0cd8acbbacec91e9ee8de [1] >> >>> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.") >> >>> Reported-and-tested-by: syzbot+03110230a11411024147@xxxxxxxxxxxxxxxxxxxxxxxxx >> >>> Reported-and-tested-by: syzbot+c6dde1f690b60e0b9fbe@xxxxxxxxxxxxxxxxxxxxxxxxx >> >>> Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx> >> >> >> >> Alright, since we've heard no more objections and the status quo is >> >> definitely broken, let's get this merged and we can follow up with any >> >> other fixes as necessary... >> >> >> >> Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxx> >> > >> > I'm wondering should these go to -rc or -next? Has anyone actually >> > tested these with real hardware? (syzbot testing does not count) With >> > the past bad experience with syzbot fixes I'm leaning towards -next to >> > have more time to fix any regressions. >> >> Hmm, good question. From Takashi's comment on v5, it seems like distros >> are going to backport it anyway, so in that sense it probably doesn't >> matter that much? > > Well, it does matter if it really breaks things, of course ;) > >> In any case I think it has a fairly low probability of breaking real >> users' setup (how often is that error path on setup even hit?), but I'm >> OK with it going to -next to be doubleplus-sure :) > > Queuing to for-next is fine for us. Backporting immediately or not > will be a decision by each distro, then. > > OTOH, if anyone has tested it beforehand on a real hardware and > confirmed, at least, that it works for normal cases (no error path), > that should suffice for -rc inclusion, too, IMO. Ok, I'll take these to -next then. I just don't like taking untested patches, having them -next gives us more time to fix any issues (or revert the patches). -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
