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authorAlexander Wetzel <alexander@wetzel-home.de>2022-04-22 16:52:28 +0200
committerKalle Valo <kvalo@kernel.org>2022-04-27 08:02:46 +0300
commit746285cf81dc19502ab238249d75f5990bd2d231 (patch)
treebd101f0d8646d3b29994acbd98bc1d6d9895f28f /drivers/net/wireless/realtek/rtl818x
parentfc6234d7e2e322e84ed3c5c6c05a54f611faa9ab (diff)
rtl818x: Prevent using not initialized queues
Using not existing queues can panic the kernel with rtl8180/rtl8185 cards. Ignore the skb priority for those cards, they only have one tx queue. Pierre Asselin (pa@panix.com) reported the kernel crash in the Gentoo forum: https://forums.gentoo.org/viewtopic-t-1147832-postdays-0-postorder-asc-start-25.html He also confirmed that this patch fixes the issue. In summary this happened: After updating wpa_supplicant from 2.9 to 2.10 the kernel crashed with a "divide error: 0000" when connecting to an AP. Control port tx now tries to use IEEE80211_AC_VO for the priority, which wpa_supplicants starts to use in 2.10. Since only the rtl8187se part of the driver supports QoS, the priority of the skb is set to IEEE80211_AC_BE (2) by mac80211 for rtl8180/rtl8185 cards. rtl8180 is then unconditionally reading out the priority and finally crashes on drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c line 544 without this patch: idx = (ring->idx + skb_queue_len(&ring->queue)) % ring->entries "ring->entries" is zero for rtl8180/rtl8185 cards, tx_ring[2] never got initialized. Cc: stable@vger.kernel.org Reported-by: pa@panix.com Tested-by: pa@panix.com Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20220422145228.7567-1-alexander@wetzel-home.de
Diffstat (limited to 'drivers/net/wireless/realtek/rtl818x')
-rw-r--r--drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c b/drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c
index 2477e18c7cae..025619cd14e8 100644
--- a/drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c
+++ b/drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c
@@ -460,8 +460,10 @@ static void rtl8180_tx(struct ieee80211_hw *dev,
struct rtl8180_priv *priv = dev->priv;
struct rtl8180_tx_ring *ring;
struct rtl8180_tx_desc *entry;
+ unsigned int prio = 0;
unsigned long flags;
- unsigned int idx, prio, hw_prio;
+ unsigned int idx, hw_prio;
+
dma_addr_t mapping;
u32 tx_flags;
u8 rc_flags;
@@ -470,7 +472,9 @@ static void rtl8180_tx(struct ieee80211_hw *dev,
/* do arithmetic and then convert to le16 */
u16 frame_duration = 0;
- prio = skb_get_queue_mapping(skb);
+ /* rtl8180/rtl8185 only has one useable tx queue */
+ if (dev->queues > IEEE80211_AC_BK)
+ prio = skb_get_queue_mapping(skb);
ring = &priv->tx_ring[prio];
mapping = dma_map_single(&priv->pdev->dev, skb->data, skb->len,