diff options
author | Juuso Oikarinen <juuso.oikarinen@nokia.com> | 2011-03-28 13:32:32 +0200 |
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committer | John W. Linville <linville@tuxdriver.com> | 2011-03-28 21:42:02 +0200 |
commit | 2b78ac9bfc7483ba4bda9ad3d10dd4afcf88337c (patch) | |
tree | da48e2e10050b2e535b908119bf60fe86b17b1e4 /net | |
parent | cfg80211:: fix possible NULL pointer dereference (diff) | |
download | linux-2b78ac9bfc7483ba4bda9ad3d10dd4afcf88337c.tar.xz linux-2b78ac9bfc7483ba4bda9ad3d10dd4afcf88337c.zip |
cfg80211: fix BSS double-unlinking (continued)
This patch adds to the fix "fix BSS double-unlinking"
(commit 3207390a8b58bfc1335750f91cf6783c48ca19ca) by Johannes Berg.
It turns out, that the double-unlinking scenario can also occur if expired
BSS elements are removed whilst an interface is performing association.
To work around that, replace list_del with list_del_init also in the
"cfg80211_bss_expire" function, so that the check for whether the BSS still is
in the list works correctly in cfg80211_unlink_bss.
Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net')
-rw-r--r-- | net/wireless/scan.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 300c11d99997..fbf6f33ae4d0 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -124,6 +124,15 @@ void cfg80211_bss_age(struct cfg80211_registered_device *dev, } /* must hold dev->bss_lock! */ +static void __cfg80211_unlink_bss(struct cfg80211_registered_device *dev, + struct cfg80211_internal_bss *bss) +{ + list_del_init(&bss->list); + rb_erase(&bss->rbn, &dev->bss_tree); + kref_put(&bss->ref, bss_release); +} + +/* must hold dev->bss_lock! */ void cfg80211_bss_expire(struct cfg80211_registered_device *dev) { struct cfg80211_internal_bss *bss, *tmp; @@ -134,9 +143,7 @@ void cfg80211_bss_expire(struct cfg80211_registered_device *dev) continue; if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE)) continue; - list_del(&bss->list); - rb_erase(&bss->rbn, &dev->bss_tree); - kref_put(&bss->ref, bss_release); + __cfg80211_unlink_bss(dev, bss); expired = true; } @@ -669,11 +676,8 @@ void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub) spin_lock_bh(&dev->bss_lock); if (!list_empty(&bss->list)) { - list_del_init(&bss->list); + __cfg80211_unlink_bss(dev, bss); dev->bss_generation++; - rb_erase(&bss->rbn, &dev->bss_tree); - - kref_put(&bss->ref, bss_release); } spin_unlock_bh(&dev->bss_lock); } |