Return-path: Received: from nbd.name ([46.4.11.11]:42840 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753149AbaBYKYE convert rfc822-to-8bit (ORCPT ); Tue, 25 Feb 2014 05:24:04 -0500 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: linville@tuxdriver.com Subject: [PATCH 3.14 2/2] ath9k: fix invalid descriptor discarding Date: Mon, 24 Feb 2014 22:26:06 +0100 Message-Id: <1393277166-28356-2-git-send-email-nbd@openwrt.org> (sfid-20140225_112433_943952_694446F1) In-Reply-To: <1393277166-28356-1-git-send-email-nbd@openwrt.org> References: <1393277166-28356-1-git-send-email-nbd@openwrt.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: Only set sc->rx.discard_next to rx_stats->rs_more when actually discarding the current descriptor. Also, fix a detection of broken descriptors: First the code checks if the current descriptor is not done. Then it checks if the next descriptor is done. Add a check that afterwards checks the first descriptor again, because it might have been completed in the mean time. This fixes a regression introduced in commit 723e711356b5a8a95728a890e254e8b0d47b55cf "ath9k: fix handling of broken descriptors" Cc: stable@vger.kernel.org Reported-by: Marco André Dinis Signed-off-by: Felix Fietkau --- drivers/net/wireless/ath/ath9k/recv.c | 70 +++++++++++++++++------------------ 1 file changed, 35 insertions(+), 35 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index a0ebdd0..82e340d 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -732,11 +732,18 @@ static struct ath_rxbuf *ath_get_next_rx_buf(struct ath_softc *sc, return NULL; /* - * mark descriptor as zero-length and set the 'more' - * flag to ensure that both buffers get discarded + * Re-check previous descriptor, in case it has been filled + * in the mean time. */ - rs->rs_datalen = 0; - rs->rs_more = true; + ret = ath9k_hw_rxprocdesc(ah, ds, rs); + if (ret == -EINPROGRESS) { + /* + * mark descriptor as zero-length and set the 'more' + * flag to ensure that both buffers get discarded + */ + rs->rs_datalen = 0; + rs->rs_more = true; + } } list_del(&bf->list); @@ -985,32 +992,32 @@ static int ath9k_rx_skb_preprocess(struct ath_softc *sc, struct ath_common *common = ath9k_hw_common(ah); struct ieee80211_hdr *hdr; bool discard_current = sc->rx.discard_next; - int ret = 0; /* * Discard corrupt descriptors which are marked in * ath_get_next_rx_buf(). */ - sc->rx.discard_next = rx_stats->rs_more; if (discard_current) - return -EINVAL; + goto corrupt; + + sc->rx.discard_next = false; /* * Discard zero-length packets. */ if (!rx_stats->rs_datalen) { RX_STAT_INC(rx_len_err); - return -EINVAL; + goto corrupt; } - /* - * rs_status follows rs_datalen so if rs_datalen is too large - * we can take a hint that hardware corrupted it, so ignore - * those frames. - */ + /* + * rs_status follows rs_datalen so if rs_datalen is too large + * we can take a hint that hardware corrupted it, so ignore + * those frames. + */ if (rx_stats->rs_datalen > (common->rx_bufsize - ah->caps.rx_status_len)) { RX_STAT_INC(rx_len_err); - return -EINVAL; + goto corrupt; } /* Only use status info from the last fragment */ @@ -1024,10 +1031,8 @@ static int ath9k_rx_skb_preprocess(struct ath_softc *sc, * This is different from the other corrupt descriptor * condition handled above. */ - if (rx_stats->rs_status & ATH9K_RXERR_CORRUPT_DESC) { - ret = -EINVAL; - goto exit; - } + if (rx_stats->rs_status & ATH9K_RXERR_CORRUPT_DESC) + goto corrupt; hdr = (struct ieee80211_hdr *) (skb->data + ah->caps.rx_status_len); @@ -1043,18 +1048,15 @@ static int ath9k_rx_skb_preprocess(struct ath_softc *sc, if (ath_process_fft(sc, hdr, rx_stats, rx_status->mactime)) RX_STAT_INC(rx_spectral); - ret = -EINVAL; - goto exit; + return -EINVAL; } /* * everything but the rate is checked here, the rate check is done * separately to avoid doing two lookups for a rate for each frame. */ - if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error)) { - ret = -EINVAL; - goto exit; - } + if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error)) + return -EINVAL; if (ath_is_mybeacon(common, hdr)) { RX_STAT_INC(rx_beacons); @@ -1064,15 +1066,11 @@ static int ath9k_rx_skb_preprocess(struct ath_softc *sc, /* * This shouldn't happen, but have a safety check anyway. */ - if (WARN_ON(!ah->curchan)) { - ret = -EINVAL; - goto exit; - } + if (WARN_ON(!ah->curchan)) + return -EINVAL; - if (ath9k_process_rate(common, hw, rx_stats, rx_status)) { - ret =-EINVAL; - goto exit; - } + if (ath9k_process_rate(common, hw, rx_stats, rx_status)) + return -EINVAL; ath9k_process_rssi(common, hw, rx_stats, rx_status); @@ -1087,9 +1085,11 @@ static int ath9k_rx_skb_preprocess(struct ath_softc *sc, sc->rx.num_pkts++; #endif -exit: - sc->rx.discard_next = false; - return ret; + return 0; + +corrupt: + sc->rx.discard_next = rx_stats->rs_more; + return -EINVAL; } static void ath9k_rx_skb_postprocess(struct ath_common *common, -- 1.8.3.4 (Apple Git-47)