From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:59873 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932730AbZJFV3Z (ORCPT ); Tue, 6 Oct 2009 17:29:25 -0400 Date: Tue, 6 Oct 2009 14:28:22 -0700 From: Andrew Morton To: Dave Young Cc: mb@bu3sch.de, linville@tuxdriver.com, bcm43xx-dev@lists.berlios.de, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: b43: fix wldev use after free Message-Id: <20091006142822.55d5120c.akpm@linux-foundation.org> In-Reply-To: <20091001084924.GA4170@darkstar> References: <20091001084924.GA4170@darkstar> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, 1 Oct 2009 16:49:24 +0800 Dave Young wrote: > when rmmod b43, I got following bug message > > [ 100.121798] BUG: unable to handle kernel paging request at 2f4066fa > [ 100.123338] IP: [] b43_unregister_led+0x6/0x1c [b43] > [ 100.123338] *pde = 00000000 > [ 100.123338] Oops: 0000 [#1] SMP > [ 100.123338] last sysfs file: /sys/devices/pci0000:00/0000:00:1c.1/0000:0c:00.0/ssb0:0/firmware/ssb0:0/loading > [ 100.123338] Modules linked in: reiserfs kvm_intel kvm snd_hda_codec_intelhdmi firewire_ohci snd_hda_codec_idt firewire_core b43(-) snd_hda_intel mac80211 snd_hda_codec crc_itu_t cfg80211 snd_hwdep ohci1394 snd_pcm dell_laptop wmi ieee1394 rfkill snd_timer snd_page_alloc > [ 100.123338] > [ 100.123338] Pid: 1931, comm: rmmod Not tainted (2.6.31-mm1 #2) Latitude E5400 > [ 100.123338] EIP: 0060:[] EFLAGS: 00010246 CPU: 0 > [ 100.123338] EIP is at b43_unregister_led+0x6/0x1c [b43] > [ 100.123338] EAX: 2f4066fa EBX: 2f4066fa ECX: 00000006 EDX: 00000246 > [ 100.123338] ESI: f6a59000 EDI: f72030a8 EBP: f6373ec8 ESP: f6373ec4 > [ 100.123338] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 > [ 100.123338] Process rmmod (pid: 1931, ti=f6372000 task=f66e0000 task.ti=f6372000) > [ 100.123338] Stack: > [ 100.123338] 2f406576 f6373ed4 f9e9dd7f f674cda0 f6373ee8 f9e8816e f72030a8 f9ea4b18 > [ 100.123338] <0> f9ea4b18 f6373ef4 c04bbd57 f7297000 f6373f04 c03f2563 f7297000 f7297034 > [ 100.123338] <0> f6373f18 c03f2609 f9ea4b18 00000000 c07742fc f6373f2c c03f1aac 00000000 > [ 100.123338] Call Trace: > [ 100.123338] [] ? b43_leds_unregister+0x12/0x36 [b43] > [ 100.123338] [] ? b43_remove+0x79/0x87 [b43] > [ 100.123338] [] ? ssb_device_remove+0x1d/0x29 > [ 100.123338] [] ? __device_release_driver+0x59/0x98 > [ 100.123338] [] ? driver_detach+0x67/0x85 > [ 100.123338] [] ? bus_remove_driver+0x63/0x7f > [ 100.123338] [] ? driver_unregister+0x4d/0x54 > [ 100.123338] [] ? ssb_driver_unregister+0xb/0xd > [ 100.123338] [] ? b43_exit+0xd/0x19 [b43] > [ 100.123338] [] ? sys_delete_module+0x17c/0x1e0 > [ 100.123338] [] ? do_page_fault+0x29d/0x2a5 > [ 100.123338] [] ? restore_all_notrace+0x0/0x18 > [ 100.123338] [] ? do_page_fault+0x0/0x2a5 > [ 100.123338] [] ? syscall_call+0x7/0xb > [ 100.123338] Code: 0f b6 93 d8 03 00 00 e8 16 ff ff ff 0f b6 8b 39 03 00 00 89 f0 0f b6 93 38 03 00 00 e8 01 ff ff ff 5b 5e 5d c3 55 89 e5 53 89 c3 <83> 38 00 74 0e 8d 40 04 e8 de cc 60 c6 c7 03 00 00 00 00 5b 5d > [ 100.123338] EIP: [] b43_unregister_led+0x6/0x1c [b43] SS:ESP 0068:f6373ec4 > [ 100.123338] CR2: 000000002f4066fa > [ 100.953375] ---[ end trace d100c06b1451fbd8 ]--- > > in b43_remove, b43_one_core_detach free the wldev, > thus following callback which reference wldev will oops. > > fix it by call b43_leds_unregister before b43_one_core_detach > if it is the last one in wl->devlist > It appears that a different fix was added to linux-next yesterday: commit 15b1803a33016745c672b74b699aaf99cf8dc0d4 Author: Michael Buesch AuthorDate: Thu Oct 1 15:54:32 2009 +0200 Commit: John W. Linville CommitDate: Mon Oct 5 17:03:16 2009 -0400 b43: Don't use struct wldev after detach. Don't use struct wldev after detach. This fixes an oops on access. Signed-off-by: Michael Buesch Signed-off-by: John W. Linville diff --git a/drivers/net/wireless/b43/leds.c b/drivers/net/wireless/b43/leds.c index fbe3d4f..1e8dba4 100644 --- a/drivers/net/wireless/b43/leds.c +++ b/drivers/net/wireless/b43/leds.c @@ -348,9 +348,9 @@ void b43_leds_register(struct b43_wldev *dev) } } -void b43_leds_unregister(struct b43_wldev *dev) +void b43_leds_unregister(struct b43_wl *wl) { - struct b43_leds *leds = &dev->wl->leds; + struct b43_leds *leds = &wl->leds; b43_unregister_led(&leds->led_tx); b43_unregister_led(&leds->led_rx); diff --git a/drivers/net/wireless/b43/leds.h b/drivers/net/wireless/b43/leds.h index 9592e4c..4c56187 100644 --- a/drivers/net/wireless/b43/leds.h +++ b/drivers/net/wireless/b43/leds.h @@ -60,7 +60,7 @@ enum b43_led_behaviour { }; void b43_leds_register(struct b43_wldev *dev); -void b43_leds_unregister(struct b43_wldev *dev); +void b43_leds_unregister(struct b43_wl *wl); void b43_leds_init(struct b43_wldev *dev); void b43_leds_exit(struct b43_wldev *dev); void b43_leds_stop(struct b43_wldev *dev); @@ -76,7 +76,7 @@ struct b43_leds { static inline void b43_leds_register(struct b43_wldev *dev) { } -static inline void b43_leds_unregister(struct b43_wldev *dev) +static inline void b43_leds_unregister(struct b43_wl *wl) { } static inline void b43_leds_init(struct b43_wldev *dev) diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index 9b907a3..130dcd5 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -4997,7 +4997,7 @@ static void b43_remove(struct ssb_device *dev) if (list_empty(&wl->devlist)) { b43_rng_exit(wl); - b43_leds_unregister(wldev); + b43_leds_unregister(wl); /* Last core on the chip unregistered. * We can destroy common struct b43_wl. */