diff options
author | Andres Salomon <dilinger@queued.net> | 2011-10-26 17:19:26 (GMT) |
---|---|---|
committer | John W. Linville <linville@tuxdriver.com> | 2011-11-02 19:23:12 (GMT) |
commit | 3209e061ad04465b3999091f315049c95ac6cbcb (patch) | |
tree | 91e1eb2eb2b0b6e8d1a0514a4de15f0c1fe8e542 /drivers/net/wireless/libertas/cfg.c | |
parent | 93348928f2c980718434b1bc42f9d7638d665db4 (diff) | |
download | linux-3209e061ad04465b3999091f315049c95ac6cbcb.tar.xz |
libertas: ensure we clean up a scan request properly
Commit 2e30168b ("libertas: terminate scan when stopping interface")
adds cleanup code to lbs_eth_stop to call cfg80211_scan_done if there's
an outstanding cfg80211_scan_request. However, it assumes that the
scan request was allocated via the cfg80211 stack. Libertas has
its own internal allocation method, kept track of with
priv->internal_scan. This doesn't set scan_req->wiphy, amongst other
things, which results in hitting a BUG() when we call cfg80211_scan_done
on the request.
This provides a function to take care of the low-level scan_req cleanup
details. We simply call that to deal with finishing up scan requests.
The bug we were hitting was:
[ 964.321495] kernel BUG at net/wireless/core.h:87!
[ 964.329970] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 964.341963] pgd = dcf80000
...
[ 964.849998] 9fe0: 00000000 beb417b8 4018e280 401e822c 60000010 00000004 00000000 00000000
[ 964.865007] [<c003104c>] (__bug+0x1c/0x28) from [<c0384ffc>] (cfg80211_scan_done+0x54/0x6c)
[ 964.895324] [<c0384ffc>] (cfg80211_scan_done+0x54/0x6c) from [<bf028bac>] (lbs_eth_stop+0x10c/0x188 [libertas])
[ 964.895324] [<bf028bac>] (lbs_eth_stop+0x10c/0x188 [libertas]) from [<c03002a0>] (__dev_close_many+0x94/0xc4)
[ 964.918995] [<c03002a0>] (__dev_close_many+0x94/0xc4) from [<c030037c>] (dev_close_many+0x78/0xe0)
Signed-off-by: Andres Salomon <dilinger@queued.net>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/libertas/cfg.c')
-rw-r--r-- | drivers/net/wireless/libertas/cfg.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/drivers/net/wireless/libertas/cfg.c b/drivers/net/wireless/libertas/cfg.c index ff63782..4fcd653 100644 --- a/drivers/net/wireless/libertas/cfg.c +++ b/drivers/net/wireless/libertas/cfg.c @@ -728,15 +728,9 @@ static void lbs_scan_worker(struct work_struct *work) le16_to_cpu(scan_cmd->hdr.size), lbs_ret_scan, 0); - if (priv->scan_channel >= priv->scan_req->n_channels) { + if (priv->scan_channel >= priv->scan_req->n_channels) /* Mark scan done */ - if (priv->internal_scan) - kfree(priv->scan_req); - else - cfg80211_scan_done(priv->scan_req, false); - - priv->scan_req = NULL; - } + lbs_scan_done(priv); /* Restart network */ if (carrier) @@ -774,6 +768,21 @@ static void _internal_start_scan(struct lbs_private *priv, bool internal, lbs_deb_leave(LBS_DEB_CFG80211); } +/* + * Clean up priv->scan_req. Should be used to handle the allocation details. + */ +void lbs_scan_done(struct lbs_private *priv) +{ + WARN_ON(!priv->scan_req); + + if (priv->internal_scan) + kfree(priv->scan_req); + else + cfg80211_scan_done(priv->scan_req, false); + + priv->scan_req = NULL; +} + static int lbs_cfg_scan(struct wiphy *wiphy, struct net_device *dev, struct cfg80211_scan_request *request) |