On Tue, Jan 28, 2020 at 4:05 PM Guenter Roeck <[email protected]> wrote:
>
> On Tue, Jan 28, 2020 at 03:14:45PM -0800, Doug Anderson wrote:
> > Hi,
> >
> > On Tue, Jan 28, 2020 at 2:15 PM Guenter Roeck <[email protected]> wrote:
> > >
> > > With commit 216b44000ada ("brcmfmac: Fix use after free in
> > > brcmf_sdio_readframes()") applied, we see locking timeouts in
> > > brcmf_sdio_watchdog_thread().
> > >
> > > brcmfmac: brcmf_escan_timeout: timer expired
> > > INFO: task brcmf_wdog/mmc1:621 blocked for more than 120 seconds.
> > > Not tainted 4.19.94-07984-g24ff99a0f713 #1
> > > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> > > brcmf_wdog/mmc1 D 0 621 2 0x00000000 last_sleep: 2440793077. last_runnable: 2440766827
> > > [<c0aa1e60>] (__schedule) from [<c0aa2100>] (schedule+0x98/0xc4)
> > > [<c0aa2100>] (schedule) from [<c0853830>] (__mmc_claim_host+0x154/0x274)
> > > [<c0853830>] (__mmc_claim_host) from [<bf10c5b8>] (brcmf_sdio_watchdog_thread+0x1b0/0x1f8 [brcmfmac])
> > > [<bf10c5b8>] (brcmf_sdio_watchdog_thread [brcmfmac]) from [<c02570b8>] (kthread+0x178/0x180)
> > >
> > > In addition to restarting or exiting the loop, it is also necessary to
> > > abort the command and to release the host.
> > >
> > > Fixes: 216b44000ada ("brcmfmac: Fix use after free in brcmf_sdio_readframes()")
> > > Cc: Dan Carpenter <[email protected]>
> > > Cc: Matthias Kaehlcke <[email protected]>
> > > Cc: Brian Norris <[email protected]>
> > > Cc: Douglas Anderson <[email protected]>
> > > Signed-off-by: Guenter Roeck <[email protected]>
> > > ---
> > > drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 2 ++
> > > 1 file changed, 2 insertions(+)
> > >
> > > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > index f9df95bc7fa1..2e1c23c7269d 100644
> > > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > @@ -1938,6 +1938,8 @@ static uint brcmf_sdio_readframes(struct brcmf_sdio *bus, uint maxframes)
> > > if (brcmf_sdio_hdparse(bus, bus->rxhdr, &rd_new,
> > > BRCMF_SDIO_FT_NORMAL)) {
> > > rd->len = 0;
> > > + brcmf_sdio_rxfail(bus, true, true);
> > > + sdio_release_host(bus->sdiodev->func1);
> >
> > I don't know much about this driver so I don't personally know if
> > "true, true" is the correct thing to pass to brcmf_sdio_rxfail(), but
> > it seems plausible. Definitely the fix to call sdio_release_host() is
> > sane.
> >
> > Thus, unless someone knows for sure that brcmf_sdio_rxfail()'s
> > parameters should be different:
> >
> Actually, looking at brcmf_sdio_hdparse() and its other callers,
> I think it may not be needed at all - other callers don't do it, and
> there already are some calls to brcmf_sdio_rxfail() in that function.
> It would be nice though to get a confirmation before I submit v2.
I think invoking rxfail with both abort and NACK set to true is the
right thing to do here so that the pipeline can be properly purged.
Thanks!
Acked-by: [email protected]
Hi Franky,
[I'm very unfamiliar with this driver, but I had the same questions as
Guenter, I think:]
On Tue, Jan 28, 2020 at 04:57:59PM -0800, Franky Lin wrote:
> On Tue, Jan 28, 2020 at 4:05 PM Guenter Roeck <[email protected]> wrote:
> > On Tue, Jan 28, 2020 at 03:14:45PM -0800, Doug Anderson wrote:
> > > On Tue, Jan 28, 2020 at 2:15 PM Guenter Roeck <[email protected]> wrote:
> > > > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > > @@ -1938,6 +1938,8 @@ static uint brcmf_sdio_readframes(struct brcmf_sdio *bus, uint maxframes)
> > > > if (brcmf_sdio_hdparse(bus, bus->rxhdr, &rd_new,
> > > > BRCMF_SDIO_FT_NORMAL)) {
> > > > rd->len = 0;
> > > > + brcmf_sdio_rxfail(bus, true, true);
> > > > + sdio_release_host(bus->sdiodev->func1);
> > >
> > > I don't know much about this driver so I don't personally know if
> > > "true, true" is the correct thing to pass to brcmf_sdio_rxfail(), but
> > > it seems plausible. Definitely the fix to call sdio_release_host() is
> > > sane.
> > >
> > > Thus, unless someone knows for sure that brcmf_sdio_rxfail()'s
> > > parameters should be different:
> > >
> > Actually, looking at brcmf_sdio_hdparse() and its other callers,
> > I think it may not be needed at all - other callers don't do it, and
> > there already are some calls to brcmf_sdio_rxfail() in that function.
> > It would be nice though to get a confirmation before I submit v2.
>
> I think invoking rxfail with both abort and NACK set to true is the
> right thing to do here so that the pipeline can be properly purged.
Thanks for looking here. I'm not sure I totally understand your answer:
brcmf_sdio_hdparse() already calls brcmf_sdio_rxfail() in several error
cases. Is it really OK to call it twice in a row?
Brian
On Wed, Jan 29, 2020 at 10:04 AM Brian Norris <[email protected]> wrote:
>
> Hi Franky,
>
> [I'm very unfamiliar with this driver, but I had the same questions as
> Guenter, I think:]
>
> On Tue, Jan 28, 2020 at 04:57:59PM -0800, Franky Lin wrote:
> > On Tue, Jan 28, 2020 at 4:05 PM Guenter Roeck <[email protected]> wrote:
> > > On Tue, Jan 28, 2020 at 03:14:45PM -0800, Doug Anderson wrote:
> > > > On Tue, Jan 28, 2020 at 2:15 PM Guenter Roeck <[email protected]> wrote:
> > > > > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > > > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> > > > > @@ -1938,6 +1938,8 @@ static uint brcmf_sdio_readframes(struct brcmf_sdio *bus, uint maxframes)
> > > > > if (brcmf_sdio_hdparse(bus, bus->rxhdr, &rd_new,
> > > > > BRCMF_SDIO_FT_NORMAL)) {
> > > > > rd->len = 0;
> > > > > + brcmf_sdio_rxfail(bus, true, true);
> > > > > + sdio_release_host(bus->sdiodev->func1);
> > > >
> > > > I don't know much about this driver so I don't personally know if
> > > > "true, true" is the correct thing to pass to brcmf_sdio_rxfail(), but
> > > > it seems plausible. Definitely the fix to call sdio_release_host() is
> > > > sane.
> > > >
> > > > Thus, unless someone knows for sure that brcmf_sdio_rxfail()'s
> > > > parameters should be different:
> > > >
> > > Actually, looking at brcmf_sdio_hdparse() and its other callers,
> > > I think it may not be needed at all - other callers don't do it, and
> > > there already are some calls to brcmf_sdio_rxfail() in that function.
> > > It would be nice though to get a confirmation before I submit v2.
> >
> > I think invoking rxfail with both abort and NACK set to true is the
> > right thing to do here so that the pipeline can be properly purged.
>
> Thanks for looking here. I'm not sure I totally understand your answer:
> brcmf_sdio_hdparse() already calls brcmf_sdio_rxfail() in several error
> cases. Is it really OK to call it twice in a row?
Yes. brcmf_sdio_rxglom does the same thing that calls
brcmf_sdio_rxfail again in error handling. For this instance I think
it's better using the same logic as the length mismatch block below (
calling brcmf_sdio_rxfail with true ture).
Thanks,
- Franky