| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <57183739.2070708@gmail.com> Date: Thu, 21 Apr 2016 10:13:13 +0800 From: Baozeng Ding <sploving1@...il.com> To: Takashi Iwai <tiwai@...e.de> Cc: yang.jie@...el.com, koro.chen@...iatek.com, lars@...afoo.de, perex@...ex.cz, alsa-devel@...a-project.org, linux-kernel@...r.kernel.org Subject: Re: Sound: BUG: KASAN: use-after-free in kill_fasync On 2016/4/6 19:37, Baozeng Ding wrote: > > > On 2016/4/5 22:18, Takashi Iwai wrote: >> On Tue, 05 Apr 2016 15:51:30 +0200, >> Baozeng Ding wrote: >>> Hi all, >>> I've got the following report (use-after-free in kill_fasync) while >>> running syzkaller. >>> Unfortunately no reproducer.The kernel version is 4.5 (on Mar 16 commit >>> 09fd671ccb2475436bd5f597f751ca4a7d177aea). >>> >>> ================================================================== >>> BUG: KASAN: use-after-free in kill_fasync+0x3fb/0x420 at addr >>> ffff880067691d88 >>> Read of size 8 by task swapper/2/0 >>> ============================================================================= >>> >>> BUG kmalloc-2048 (Not tainted): kasan: bad access detected >>> ----------------------------------------------------------------------------- >>> >>> >>> Disabling lock debugging due to kernel taint >>> INFO: Allocated in 0xbbbbbbbbbbbbbbbb age=18446678412249576073 >>> cpu=2245704320 pid=-1 >>> [< inline >] kmalloc /kernel/include/linux/slab.h:472 >>> [< inline >] kzalloc /kernel/include/linux/slab.h:616 >>> [< none >] snd_pcm_attach_substream+0x3b4/0xb10 >>> /kernel/sound/core/pcm.c:966 >>> [< none >] ___slab_alloc+0x4c7/0x500 /kernel/mm/slub.c:2446 >>> [< none >] __slab_alloc+0x4c/0x90 /kernel/mm/slub.c:2475 >>> [< inline >] slab_alloc_node /kernel/mm/slub.c:2538 >>> [< inline >] slab_alloc /kernel/mm/slub.c:2580 >>> [< none >] kmem_cache_alloc_trace+0x262/0x300 >>> /kernel/mm/slub.c:2597 >>> [< inline >] kmalloc /kernel/include/linux/slab.h:472 >>> [< inline >] kzalloc /kernel/include/linux/slab.h:616 >>> [< none >] snd_pcm_attach_substream+0x3b4/0xb10 >>> /kernel/sound/core/pcm.c:966 >>> [< none >] snd_pcm_open_substream+0x84/0x450 >>> /kernel/sound/core/pcm_native.c:2262 >>> [< inline >] snd_pcm_oss_open_file >>> /kernel/sound/core/oss/pcm_oss.c:2346 >>> [< none >] snd_pcm_oss_open.part.17+0x5a4/0x1100 >>> /kernel/sound/core/oss/pcm_oss.c:2428 >>> [< none >] snd_pcm_oss_open+0x35/0x50 >>> /kernel/sound/core/oss/pcm_oss.c:2392 >>> [< none >] soundcore_open+0x30f/0x640 >>> /kernel/sound/sound_core.c:639 >>> [< none >] chrdev_open+0x22a/0x4c0 /kernel/fs/char_dev.c:388 >>> [< none >] do_dentry_open+0x6a2/0xcb0 /kernel/fs/open.c:736 >>> [< none >] vfs_open+0x17b/0x1f0 /kernel/fs/open.c:853 >>> [< inline >] do_last /kernel/fs/namei.c:3258 >>> [< none >] path_openat+0x4837/0x5830 /kernel/fs/namei.c:3394 >>> [< none >] do_filp_open+0x18e/0x250 /kernel/fs/namei.c:3429 >>> [< none >] do_sys_open+0x201/0x420 /kernel/fs/open.c:1022 >>> [< inline >] SYSC_open /kernel/fs/open.c:1040 >>> [< none >] SyS_open+0x2d/0x40 /kernel/fs/open.c:1035 >>> INFO: Freed in 0x10000b076 age=18446678416544543380 cpu=0 pid=0 >>> [< none >] snd_pcm_detach_substream+0x134/0x280 >>> /kernel/sound/core/pcm.c:1017 >>> [< none >] __slab_free+0x1e8/0x300 /kernel/mm/slub.c:2657 >>> [< inline >] slab_free /kernel/mm/slub.c:2810 >>> [< none >] kfree+0x24e/0x2d0 /kernel/mm/slub.c:3661 >>> [< none >] snd_pcm_detach_substream+0x134/0x280 >>> /kernel/sound/core/pcm.c:1017 >>> [< none >] snd_pcm_release_substream.part.38+0x219/0x2f0 >>> /kernel/sound/core/pcm_native.c:2250 >>> [< none >] snd_pcm_release_substream+0x59/0x70 >>> /kernel/sound/core/pcm_native.c:2251 >>> [< none >] snd_pcm_oss_release_file+0x45/0xb0 >>> /kernel/sound/core/oss/pcm_oss.c:2305 >>> [< none >] snd_pcm_oss_release+0xfa/0x250 >>> /kernel/sound/core/oss/pcm_oss.c:2485 >>> [< none >] __fput+0x236/0x780 /kernel/fs/file_table.c:208 >>> [< none >] ____fput+0x15/0x20 /kernel/fs/file_table.c:244 >>> [< none >] task_work_run+0x16b/0x200 >>> /kernel/kernel/task_work.c:115 >>> [< inline >] exit_task_work >>> /kernel/include/linux/task_work.h:21 >>> [< none >] do_exit+0x87f/0x2c90 /kernel/kernel/exit.c:748 >>> [< none >] do_group_exit+0x108/0x330 >>> /kernel/kernel/exit.c:878 >>> [< inline >] SYSC_exit_group /kernel/kernel/exit.c:889 >>> [< none >] SyS_exit_group+0x1d/0x20 /kernel/kernel/exit.c:887 >>> [< none >] entry_SYSCALL_64_fastpath+0x23/0xc1 >>> /kernel/arch/x86/entry/entry_64.S:207 >>> INFO: Slab 0xffffea00019da400 objects=13 used=8 fp=0xffff880067691be0 >>> flags=0x5fffc0000004080 >>> INFO: Object 0xffff880067691bd8 @offset=7128 fp=0xbbbbbbbbbbbbbbbb >>> Call Trace: >>> <IRQ> [< inline >] __dump_stack /kernel/lib/dump_stack.c:15 >>> <IRQ> [<ffffffff82945051>] dump_stack+0xb3/0x112 >>> /kernel/lib/dump_stack.c:51 >>> [<ffffffff817009ad>] print_trailer+0x10d/0x190 /kernel/mm/slub.c:668 >>> [<ffffffff817074af>] object_err+0x2f/0x40 /kernel/mm/slub.c:675 >>> [< inline >] print_address_description >>> /kernel/mm/kasan/report.c:138 >>> [<ffffffff81709ca5>] kasan_report_error+0x215/0x530 >>> /kernel/mm/kasan/report.c:236 >>> [< inline >] ? spin_lock >>> /kernel/include/linux/spinlock.h:302 >>> [<ffffffff84a1c550>] ? snd_pcm_stream_lock+0x80/0xd0 >>> /kernel/sound/core/pcm_native.c:104 >>> [< inline >] kasan_report /kernel/mm/kasan/report.c:259 >>> [<ffffffff8170a0be>] __asan_report_load8_noabort+0x3e/0x40 >>> /kernel/mm/kasan/report.c:280 >>> [<ffffffff81792a0b>] ? kill_fasync+0x3fb/0x420 >>> /kernel/fs/fcntl.c:729 >>> [<ffffffff81792a0b>] kill_fasync+0x3fb/0x420 /kernel/fs/fcntl.c:729 >>> [<ffffffff84a36e08>] snd_pcm_period_elapsed+0x1c8/0x230 >>> /kernel/sound/core/pcm_lib.c:1890 >>> [<ffffffff84b6e2e0>] ? get_bound_vga.isra.21.part.22+0x140/0x140 >>> /kernel/sound/pci/hda/hda_intel.c:1327 >>> [<ffffffff84b0637d>] stream_update+0xad/0xe0 >>> /kernel/sound/pci/hda/hda_controller.c:923 >>> [<ffffffff84c1583e>] snd_hdac_bus_handle_stream_irq+0x24e/0x350 >>> /kernel/sound/hda/hdac_controller.c:449 >>> [<ffffffff84b062d0>] ? azx_init_chip+0x100/0x100 >>> /kernel/sound/pci/hda/hda_controller.c:890 >>> [<ffffffff84b04d24>] ? azx_interrupt+0x14/0x4d0 >>> /kernel/sound/pci/hda/hda_controller.c:929 >>> [<ffffffff84b04eee>] azx_interrupt+0x1de/0x4d0 >>> /kernel/sound/pci/hda/hda_controller.c:954 >>> [<ffffffff84b04d10>] ? azx_stop_chip+0x20/0x20 >>> /kernel/sound/pci/hda/hda_controller.c:908 >>> [<ffffffff8143d9e3>] handle_irq_event_percpu+0xf3/0x790 >>> /kernel/kernel/irq/handle.c:145 >>> [<ffffffff8143e127>] handle_irq_event+0xa7/0x140 >>> /kernel/kernel/irq/handle.c:192 >>> [<ffffffff81447f81>] handle_edge_irq+0x1e1/0x8d0 >>> /kernel/kernel/irq/chip.c:623 >>> [< inline >] generic_handle_irq_desc >>> /kernel/include/linux/irqdesc.h:146 >>> [<ffffffff811ad739>] handle_irq+0x109/0x2a0 >>> /kernel/arch/x86/kernel/irq_64.c:78 >>> [< inline >] ? rcu_lock_release >>> /kernel/include/linux/rcupdate.h:491 >>> [< inline >] ? rcu_read_unlock >>> /kernel/include/linux/rcupdate.h:926 >>> [< inline >] ? __atomic_notifier_call_chain >>> /kernel/kernel/notifier.c:184 >>> [<ffffffff81369c4f>] ? atomic_notifier_call_chain+0xbf/0x140 >>> /kernel/kernel/notifier.c:193 >>> [<ffffffff81369b90>] ? __atomic_notifier_call_chain+0x150/0x150 >>> /kernel/include/linux/rcupdate.h:922 >>> [<ffffffff811ac36d>] do_IRQ+0x7d/0x1a0 >>> /kernel/arch/x86/kernel/irq.c:240 >>> [<ffffffff85dac40c>] common_interrupt+0x8c/0x8c >>> /kernel/arch/x86/entry/entry_64.S:454 >>> <EOI> [<ffffffff812245c6>] ? native_safe_halt+0x6/0x10 >>> /kernel/./arch/x86/include/asm/irqflags.h:49 >>> [<ffffffff81405ced>] ? trace_hardirqs_on+0xd/0x10 >>> /kernel/kernel/locking/lockdep.c:2635 >>> [< inline >] arch_safe_halt >>> /kernel/./arch/x86/include/asm/paravirt.h:117 >>> [<ffffffff811bf152>] default_idle+0x22/0x2d0 >>> /kernel/arch/x86/kernel/process.c:307 >>> [<ffffffff811c053a>] arch_cpu_idle+0xa/0x10 >>> /kernel/arch/x86/kernel/process.c:298 >>> [<ffffffff813eb618>] default_idle_call+0x48/0x70 >>> /kernel/kernel/sched/idle.c:93 >>> [< inline >] cpuidle_idle_call >>> /kernel/kernel/sched/idle.c:151 >>> [< inline >] cpu_idle_loop /kernel/kernel/sched/idle.c:242 >>> [<ffffffff813ebaa7>] cpu_startup_entry+0x467/0x600 >>> /kernel/kernel/sched/idle.c:291 >>> [<ffffffff81201432>] start_secondary+0x2b2/0x380 >>> /kernel/arch/x86/kernel/smpboot.c:259 >>> [<ffffffff81201180>] ? set_cpu_sibling_map+0x18a0/0x18a0 >>> /kernel/include/linux/topology.h:80 >>> Memory state around the buggy address: >>> ffff880067691c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>> ffff880067691d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>> >ffff880067691d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>> ^ >>> ffff880067691e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>> ffff880067691e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>> ================================================================== >>> >>> It seems that in function snd_pcm_detach_substream, when freeing >>> runtime >>> structure, it did not handle its fasync >>> data pointer. Any ideas? Thanks. >> Well, fasync doesn't need a cleanup usually. Do you have a proper >> reproducer code? > Sorry, I cannot reproduce it. I will apply your patch and test it. I > will tell you the result whether it is okay a few days later. > Thanks. > >> In anyway, try the patch below. I'm not sure whether this would help, >> but if the path is via kill_fasync(), it'd be good to put in the >> protected context. >> During the last few weeks, I have not seen the bug any more after applying your patch. Thanks. >> >> Takashi >> >> --- >> diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c >> index 3a9b66c6e09c..0aca39762ed0 100644 >> --- a/sound/core/pcm_lib.c >> +++ b/sound/core/pcm_lib.c >> @@ -1886,8 +1886,8 @@ void snd_pcm_period_elapsed(struct >> snd_pcm_substream *substream) >> snd_timer_interrupt(substream->timer, 1); >> #endif >> _end: >> - snd_pcm_stream_unlock_irqrestore(substream, flags); >> kill_fasync(&runtime->fasync, SIGIO, POLL_IN); >> + snd_pcm_stream_unlock_irqrestore(substream, flags); >> } >> EXPORT_SYMBOL(snd_pcm_period_elapsed); >
Powered by blists - more mailing lists