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logang@deltatee.com, perex@perex.cz, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, tiwai@suse.com X-Mailman-Approved-At: Tue, 12 Nov 2019 11:14:25 +0100 Subject: [alsa-devel] KASAN: use-after-free Read in snd_timer_open X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed"; DelSp="yes" Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" Hello, syzbot found the following crash on: HEAD commit: 6980b7f6 Add linux-next specific files for 20191111 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=101679e6e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=2af7db1972ec750e dashboard link: https://syzkaller.appspot.com/bug?extid=4476917c053f60112c99 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=108fbfece00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1055d5aae00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+4476917c053f60112c99@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in __list_add_valid+0x9a/0xa0 lib/list_debug.c:26 Read of size 8 at addr ffff88809fccee78 by task syz-executor075/8825 CPU: 0 PID: 8825 Comm: syz-executor075 Not tainted 5.4.0-rc6-next-20191111 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __list_add_valid+0x9a/0xa0 lib/list_debug.c:26 __list_add include/linux/list.h:60 [inline] list_add_tail include/linux/list.h:93 [inline] snd_timer_open+0x245/0x1150 sound/core/timer.c:268 snd_timer_user_tselect sound/core/timer.c:1738 [inline] __snd_timer_user_ioctl.isra.0+0x7ed/0x2070 sound/core/timer.c:2008 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2038 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x444f39 Code: e8 fc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb cd fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffd1d1e3c98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444f39 RDX: 0000000020029fcc RSI: 0000000040345410 RDI: 0000000000000003 RBP: 00000000000102a7 R08: 0000000000000004 R09: 00000000004002e0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000402180 R13: 0000000000402210 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 8824: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:670 [inline] snd_timer_instance_new+0x4a/0x300 sound/core/timer.c:96 snd_timer_user_tselect sound/core/timer.c:1725 [inline] __snd_timer_user_ioctl.isra.0+0x665/0x2070 sound/core/timer.c:2008 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2038 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8824: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 snd_timer_instance_free sound/core/timer.c:120 [inline] snd_timer_instance_free+0x7c/0xa0 sound/core/timer.c:114 snd_timer_user_tselect sound/core/timer.c:1740 [inline] __snd_timer_user_ioctl.isra.0+0x160d/0x2070 sound/core/timer.c:2008 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2038 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88809fccee00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 120 bytes inside of 256-byte region [ffff88809fccee00, ffff88809fccef00) The buggy address belongs to the page: page:ffffea00027f3380 refcount:1 mapcount:0 mapping:ffff8880aa4008c0 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00027f2e08 ffff8880aa401648 ffff8880aa4008c0 raw: 0000000000000000 ffff88809fcce000 0000000100000008 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809fcced00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809fcced80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff88809fccee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809fccee80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809fccef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88493C43331 for ; Mon, 11 Nov 2019 16:34:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AD9C20656 for ; Mon, 11 Nov 2019 16:34:14 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zbviiuHdWZllgCrurJ9kC5xo0Bs8B5XxLPAG7CBEafkik4C2wHsfcrebPoOGZxCFeCMB GMqg== X-Gm-Message-State: APjAAAUfvj76jeasZjIMQUsKAJLcjq8Zz6esGg5EgaRjR7s7Mmvuwlx7 bLRA+nlojyPsHH4yKKjx6Mlra12Pj6TgsQRZEGMIORBERcLI X-Google-Smtp-Source: APXvYqyoarDaLS6lJ4bI+TURCZBTw5+IRtgnAdvuq/tSHY2RA9V8+HS/vn1F0lbwGtcBgApOIN9onlL6p3dp6i4kGQcKbNFxJNm7 MIME-Version: 1.0 X-Received: by 2002:a5e:9706:: with SMTP id w6mr2987651ioj.252.1573490050160; Mon, 11 Nov 2019 08:34:10 -0800 (PST) Date: Mon, 11 Nov 2019 08:34:10 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000007f69a2059714b34d@google.com> Subject: KASAN: use-after-free Read in snd_timer_open From: syzbot To: alexandre.belloni@bootlin.com, allison@lohutok.net, alsa-devel@alsa-project.org, kirr@nexedi.com, linux-kernel@vger.kernel.org, logang@deltatee.com, perex@perex.cz, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, tiwai@suse.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 6980b7f6 Add linux-next specific files for 20191111 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=101679e6e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=2af7db1972ec750e dashboard link: https://syzkaller.appspot.com/bug?extid=4476917c053f60112c99 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=108fbfece00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1055d5aae00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+4476917c053f60112c99@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in __list_add_valid+0x9a/0xa0 lib/list_debug.c:26 Read of size 8 at addr ffff88809fccee78 by task syz-executor075/8825 CPU: 0 PID: 8825 Comm: syz-executor075 Not tainted 5.4.0-rc6-next-20191111 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 __list_add_valid+0x9a/0xa0 lib/list_debug.c:26 __list_add include/linux/list.h:60 [inline] list_add_tail include/linux/list.h:93 [inline] snd_timer_open+0x245/0x1150 sound/core/timer.c:268 snd_timer_user_tselect sound/core/timer.c:1738 [inline] __snd_timer_user_ioctl.isra.0+0x7ed/0x2070 sound/core/timer.c:2008 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2038 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x444f39 Code: e8 fc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb cd fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffd1d1e3c98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444f39 RDX: 0000000020029fcc RSI: 0000000040345410 RDI: 0000000000000003 RBP: 00000000000102a7 R08: 0000000000000004 R09: 00000000004002e0 R10: 000000000000000f R11: 0000000000000246 R12: 0000000000402180 R13: 0000000000402210 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 8824: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:510 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:670 [inline] snd_timer_instance_new+0x4a/0x300 sound/core/timer.c:96 snd_timer_user_tselect sound/core/timer.c:1725 [inline] __snd_timer_user_ioctl.isra.0+0x665/0x2070 sound/core/timer.c:2008 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2038 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8824: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 snd_timer_instance_free sound/core/timer.c:120 [inline] snd_timer_instance_free+0x7c/0xa0 sound/core/timer.c:114 snd_timer_user_tselect sound/core/timer.c:1740 [inline] __snd_timer_user_ioctl.isra.0+0x160d/0x2070 sound/core/timer.c:2008 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2038 vfs_ioctl fs/ioctl.c:47 [inline] file_ioctl fs/ioctl.c:545 [inline] do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732 ksys_ioctl+0xab/0xd0 fs/ioctl.c:749 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88809fccee00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 120 bytes inside of 256-byte region [ffff88809fccee00, ffff88809fccef00) The buggy address belongs to the page: page:ffffea00027f3380 refcount:1 mapcount:0 mapping:ffff8880aa4008c0 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00027f2e08 ffff8880aa401648 ffff8880aa4008c0 raw: 0000000000000000 ffff88809fcce000 0000000100000008 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809fcced00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809fcced80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff88809fccee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809fccee80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809fccef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches