During initialization we would not have received any beacons so skip processing reg beacon hints, also adds a check to reg_is_world_roaming() for last_request before accessing its fields. This should fix this: BUG: unable to handle kernel NULL pointer dereference at IP: [<e0171332>] wiphy_update_regulatory+0x20f/0x295 *pdpt = 0000000008bf1001 *pde = 0000000000000000 Oops: 0000 [#1] last sysfs file: /sys/class/backlight/eeepc/brightness Modules linked in: ath5k(+) mac80211 led_class cfg80211 go_bit cfbcopyarea cfbimgblt cfbfillrect ipv6 ydev usual_tables(P) snd_hda_codec_realtek snd_hda_intel nd_hwdep uhci_hcd snd_pcm_oss snd_mixer_oss i2c_i801 e serio_raw i2c_core pcspkr atl2 snd_pcm intel_agp re agpgart eeepc_laptop snd_page_alloc ac video backlight rfkill button processor evdev thermal fan ata_generic Pid: 2909, comm: modprobe Tainted: Pc #112) 701 EIP: 0060:[<e0171332>] EFLAGS: 00010246 CPU: 0 EIP is at wiphy_update_regulatory+0x20f/0x295 [cfg80211] EAX: 00000000 EBX: c5da0000 ECX: 00000000 EDX: c5da0060 ESI: 0000001a EDI: c5da0060 EBP: df3bdd70 ESP: df3bdd40 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 Process modprobe (pid: 2909, ti=df3bc000 task=c5d030000) Stack: df3bdd90 c5da0060 c04277e0 00000001 00000044 c04277e402 00000002 c5da0000 0000001a c5da0060 df3bdda8 e01706a2 02 00000282 000080d0 00000068 c5d53500 00000080 0000028240 Call Trace: [<e01706a2>] ? wiphy_register+0x122/0x1b7 [cfg80211] [<e0328e02>] ? ieee80211_register_hw+0xd8/0x346 [<e06a7c9f>] ? ath5k_hw_set_bssid_mask+0x71/0x78 [ath5k] [<e06b0c52>] ? ath5k_pci_probe+0xa5c/0xd0a [ath5k] [<c01a6037>] ? sysfs_find_dirent+0x16/0x27 [<c01fec95>] ? local_pci_probe+0xe/0x10 [<c01ff526>] ? pci_device_probe+0x48/0x66 [<c024c9fd>] ? driver_probe_device+0x7f/0xf2 [<c024cab3>] ? __driver_attach+0x43/0x5f [<c024c0af>] ? bus_for_each_dev+0x39/0x5a [<c024c8d0>] ? driver_attach+0x14/0x16 [<c024ca70>] ? __driver_attach+0x0/0x5f [<c024c5b3>] ? bus_add_driver+0xd7/0x1e7 [<c024ccb9>] ? driver_register+0x7b/0xd7 [<c01ff827>] ? __pci_register_driver+0x32/0x85 [<e00a8018>] ? init_ath5k_pci+0x18/0x30 [ath5k] [<c0101131>] ? _stext+0x49/0x10b [<e00a8000>] ? init_ath5k_pci+0x0/0x30 [ath5k] [<c012f452>] ? __blocking_notifier_call_chain+0x40/0x4c [<c013a714>] ? sys_init_module+0x87/0x18b [<c0102804>] ? sysenter_do_call+0x12/0x22 Code: b8 da 17 e0 83 c0 04 e8 92 f9 ff ff 84 c0 75 2a 8b 85 c0 74 0c 83 c0 04 e8 7c f9 ff ff 84 c0 75 14 a1 bc da 4 03 74 66 8b 4d d4 80 79 08 00 74 5d a1 e0 d2 17 e0 48 EIP: [<e0171332>] wiphy_update_regulatory+0x20f/0x295 SP 0068:df3bdd40 CR2: 0000000000000004 ---[ end trace 830f2dd2a95fd1a8 ]--- This issue is hard to reproduce, but it was noticed and discussed on this thread: http://marc.info/?t=123938022700005&r=1&w=2 Cc: stable@xxxxxxxxxx Reported-by: Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx> --- net/wireless/reg.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-) diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 11481b4..d68950d 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -1135,7 +1135,8 @@ static bool reg_is_world_roaming(struct wiphy *wiphy) if (is_world_regdom(cfg80211_regdomain->alpha2) || (wiphy->regd && is_world_regdom(wiphy->regd->alpha2))) return true; - if (last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE && + if (last_request && + last_request->initiator != NL80211_REGDOM_SET_BY_COUNTRY_IE && wiphy->custom_regulatory) return true; return false; @@ -1144,6 +1145,12 @@ static bool reg_is_world_roaming(struct wiphy *wiphy) /* Reap the advantages of previously found beacons */ static void reg_process_beacons(struct wiphy *wiphy) { + /* + * Means we are just firing up cfg80211, so no beacons would + * have been processed yet. + */ + if (!last_request) + return; if (!reg_is_world_roaming(wiphy)) return; wiphy_update_beacon_reg(wiphy); -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
