From 0d422f4237ce515678ebbb8781881e5d2e58b9d4 Mon Sep 17 00:00:00 2001 From: Vasanthakumar Thiagarajan Date: Wed, 1 Jun 2011 13:44:11 +0530 Subject: [PATCH] staging: ath6kl: Fix a kernel panic during suspend/resume The kernel panic happens when we try to complete a pending scan request while going to suspend state. The cause for this kernel panic is accessing a freed memory (ar->arWmin). This is freed before ar6k_cfg80211_scanComplete_event() getting called where it is dereferenced. RIP: 0010:[] [] wlan_iterate_nodes+0x16/0xc0 [ath6kl] RSP: 0018:ffff8800719fbce8 EFLAGS: 00010296 RAX: ffff880071bbcc00 RBX: ffff880037b22520 RCX: ffff880077413c80 RDX: ffff880037b221c0 RSI: ffffffffa041ef10 RDI: 0000000000000020 RBP: ffff8800719fbd18 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000400 R11: 0000000000000000 R12: 0000000000000010 R13: ffff8800719fbdd8 R14: 00007fff83a84b60 R15: 0000000000000001 FS: 00007fdccb8a7700(0000) GS:ffff880077400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000148 CR3: 0000000070604000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process rmmod (pid: 1998, threadinfo ffff8800719fa000, task ffff880066712d80) Stack: 0000000000000000 ffff880037b22520 0000000000000010 ffff8800719fbdd8 00007fff83a84b60 0000000000000001 ffff8800719fbd28 ffffffffa0429fe2 ffff8800719fbd58 ffffffffa041ee5f ffff8800719fbd58 ffff880037b22520 Call Trace: [] wmi_iterate_nodes+0x12/0x20 [ath6kl] [] ar6k_cfg80211_scanComplete_event+0x3f/0xf0 [ath6kl] [] ar6000_close+0x61/0x100 [ath6kl] [] __dev_close_many+0x96/0x100 [] dev_close_many+0x9d/0x120 [] rollback_registered_many+0xe8/0x290 [] unregister_netdevice_queue+0x96/0x100 [] unregister_netdev+0x20/0x30 [] ar6000_destroy+0x119/0x180 [ath6kl] [] ar6k_cleanup_module+0x2a/0x33 [ath6kl] [] sys_delete_module+0x19e/0x270 [] system_call_fastpath+0x16/0x1b Code: c3 0f 1f 40 00 48 89 df e8 68 ff ff ff eb df 66 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 08 0f 1f 44 00 00 8b af 28 01 00 00 4c 8d 7f 08 49 89 fc 48 89 f3 49 89 d6 41 RIP [] wlan_iterate_nodes+0x16/0xc0 [ath6kl] RSP Signed-off-by: Vasanthakumar Thiagarajan Signed-off-by: Greg Kroah-Hartman --- drivers/staging/ath6kl/os/linux/cfg80211.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/ath6kl/os/linux/cfg80211.c b/drivers/staging/ath6kl/os/linux/cfg80211.c index 77dfb4070c1..d3a774dbb7e 100644 --- a/drivers/staging/ath6kl/os/linux/cfg80211.c +++ b/drivers/staging/ath6kl/os/linux/cfg80211.c @@ -870,7 +870,8 @@ ar6k_cfg80211_scanComplete_event(struct ar6_softc *ar, int status) if(ar->scan_request) { /* Translate data to cfg80211 mgmt format */ - wmi_iterate_nodes(ar->arWmi, ar6k_cfg80211_scan_node, ar->wdev->wiphy); + if (ar->arWmi) + wmi_iterate_nodes(ar->arWmi, ar6k_cfg80211_scan_node, ar->wdev->wiphy); cfg80211_scan_done(ar->scan_request, ((status & A_ECANCELED) || (status & A_EBUSY)) ? true : false); -- 2.39.5