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=-8.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 A8743C636CA for ; Sat, 17 Jul 2021 06:22:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6FB8F613C3 for ; Sat, 17 Jul 2021 06:22:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230464AbhGQGZR (ORCPT ); Sat, 17 Jul 2021 02:25:17 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:40614 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229379AbhGQGZP (ORCPT ); Sat, 17 Jul 2021 02:25:15 -0400 Received: by mail-io1-f69.google.com with SMTP id l15-20020a5e820f0000b02904bd1794d00eso7762510iom.7 for ; Fri, 16 Jul 2021 23:22:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=i1Msp2SDDRstktfWajozsgaj/LRf5a1wJhC9VT9U5w4=; b=pLc+LVEIKGfvgOLiCEtd4Bnq3y9ULY0qf5wkbokNbQALEIJf7XI+etYw7UAdzUtB/q mmJH/ZM5PSCcOCRb8vsAyfqQAvMJ6RR3j+eed6qKwVH/JWIDmPdwgmJvdXeorvdxGw27 3So8xwM2aN/tARcfD2vA/xwETz9eacwj1C2UnYpGCEHygMozgb7HuC72msU4IpKeMfeV FNgdtecX9IIjtUfT+OHwl1jlN17adJhyL57SW9LGcmuN6hG4Ej1rGur95aMovsc1XAEg 1xR/MkHwA+aDYgxs71U4yCjXwoanCu+/J5yWLkIH1q86ip69yOsHWLF2CdUjo090CwKQ h/dA== X-Gm-Message-State: AOAM531QQ0KZCtQo8AQ7eyw2szqU8MSzZcg0yQ2oMPPENM6HdBUnrnDX oQCKJiveOojBIyI5bJG9B/d3Wd/f0RgoJmj7t//FVByu/2Tv X-Google-Smtp-Source: ABdhPJy8cc6WS7WK2vMrHFeMgB8E7DvNpqXu/K9pT7CgUhrHu9b9M/Egkwh+Hie8+cVxXOTvK/gxik9kEiTsix8R5NjFQJoGjrU+ MIME-Version: 1.0 X-Received: by 2002:a6b:7b44:: with SMTP id m4mr10179487iop.72.1626502939533; Fri, 16 Jul 2021 23:22:19 -0700 (PDT) Date: Fri, 16 Jul 2021 23:22:19 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000efe97f05c74bb995@google.com> Subject: [syzbot] KASAN: use-after-free Write in put_ucounts From: syzbot To: ebiederm@xmission.com, legion@kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 3dbdb38e2869 Merge branch 'for-5.14' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1541de9c300000 kernel config: https://syzkaller.appspot.com/x/.config?x=a1fcf15a09815757 dashboard link: https://syzkaller.appspot.com/bug?extid=b6e65bd125a05f803d6b userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+b6e65bd125a05f803d6b@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic_dec_and_test include/asm-generic/atomic-instrumented.h:542 [inline] BUG: KASAN: use-after-free in put_ucounts+0x1c/0x150 kernel/ucount.c:196 Write of size 4 at addr ffff88801c86cc1c by task kworker/u4:3/166 CPU: 0 PID: 166 Comm: kworker/u4:3 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:96 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_dec_and_test include/asm-generic/atomic-instrumented.h:542 [inline] put_ucounts+0x1c/0x150 kernel/ucount.c:196 put_cred_rcu+0x27a/0x520 kernel/cred.c:124 rcu_do_batch kernel/rcu/tree.c:2558 [inline] rcu_core+0x7ab/0x1380 kernel/rcu/tree.c:2793 __do_softirq+0x29b/0x9bd kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5593 Code: e1 a6 7e 83 f8 01 0f 85 a6 02 00 00 9c 58 f6 c4 02 0f 85 91 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900010bfba8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000217f77 RCX: 3f6e7590f6a9846c RDX: 1ffff1100283613d RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff9049d8a7 R10: fffffbfff2093b14 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8c17bb80 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:267 [inline] rcu_read_lock include/linux/rcupdate.h:671 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:404 [inline] batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:715 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 8622: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] alloc_ucounts+0x23d/0x5b0 kernel/ucount.c:169 set_cred_ucounts+0x171/0x3a0 kernel/cred.c:684 copy_creds+0x853/0xb20 kernel/cred.c:375 copy_process+0x1413/0x74c0 kernel/fork.c:1992 kernel_clone+0xe7/0xab0 kernel/fork.c:2509 __do_compat_sys_ia32_clone+0xac/0xe0 arch/x86/kernel/sys_ia32.c:254 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] do_int80_syscall_32+0x46/0x90 arch/x86/entry/common.c:132 entry_INT80_compat+0x71/0x76 arch/x86/entry/entry_64_compat.S:413 Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 insert_work+0x48/0x370 kernel/workqueue.c:1332 __queue_work+0x5c1/0xed0 kernel/workqueue.c:1498 queue_work_on+0xee/0x110 kernel/workqueue.c:1525 queue_work include/linux/workqueue.h:507 [inline] call_usermodehelper_exec+0x1f0/0x4c0 kernel/umh.c:435 kobject_uevent_env+0xf8f/0x1650 lib/kobject_uevent.c:618 kobject_synth_uevent+0x701/0x850 lib/kobject_uevent.c:208 uevent_store+0x20/0x50 drivers/base/core.c:2370 dev_attr_store+0x50/0x80 drivers/base/core.c:2071 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x342/0x500 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x796/0xa30 fs/read_write.c:605 ksys_write+0x12d/0x250 fs/read_write.c:658 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 insert_work+0x48/0x370 kernel/workqueue.c:1332 __queue_work+0x5c1/0xed0 kernel/workqueue.c:1498 queue_work_on+0xee/0x110 kernel/workqueue.c:1525 queue_work include/linux/workqueue.h:507 [inline] call_usermodehelper_exec+0x1f0/0x4c0 kernel/umh.c:435 kobject_uevent_env+0xf8f/0x1650 lib/kobject_uevent.c:618 kobject_synth_uevent+0x701/0x850 lib/kobject_uevent.c:208 uevent_store+0x42/0x90 drivers/base/bus.c:585 drv_attr_store+0x6d/0xa0 drivers/base/bus.c:77 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x342/0x500 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x796/0xa30 fs/read_write.c:605 ksys_write+0x12d/0x250 fs/read_write.c:658 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88801c86cc00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 28 bytes inside of 192-byte region [ffff88801c86cc00, ffff88801c86ccc0) The buggy address belongs to the page: page:ffffea0000721b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801c86cc00 pfn:0x1c86c flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea00009f0e48 ffffea00009cd188 ffff888011041a00 raw: ffff88801c86cc00 000000000010000b 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 7975119940, free_ts 7474437105 prep_new_page mm/page_alloc.c:2445 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4178 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5386 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2147 alloc_pages+0x238/0x2a0 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1702 [inline] allocate_slab+0x32b/0x4c0 mm/slub.c:1842 new_slab mm/slub.c:1905 [inline] new_slab_objects mm/slub.c:2651 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2814 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2854 slab_alloc_node mm/slub.c:2936 [inline] slab_alloc mm/slub.c:2978 [inline] kmem_cache_alloc_trace+0x325/0x3c0 mm/slub.c:2995 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] call_usermodehelper_setup+0x97/0x340 kernel/umh.c:365 kobject_uevent_env+0xf73/0x1650 lib/kobject_uevent.c:614 device_add+0xb71/0x2100 drivers/base/core.c:3305 register_virtio_device+0x1e1/0x2c0 drivers/virtio/virtio.c:363 virtio_pci_probe+0x203/0x390 drivers/virtio/virtio_pci_common.c:552 local_pci_probe+0xdb/0x190 drivers/pci/pci-driver.c:309 pci_call_probe drivers/pci/pci-driver.c:366 [inline] __pci_device_probe drivers/pci/pci-driver.c:391 [inline] pci_device_probe+0x3dd/0x6f0 drivers/pci/pci-driver.c:434 really_probe+0x291/0xf60 drivers/base/dd.c:576 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1355 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3341 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3420 __vunmap+0x783/0xb70 mm/vmalloc.c:2569 free_work+0x58/0x70 mm/vmalloc.c:80 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88801c86cb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801c86cb80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801c86cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801c86cc80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88801c86cd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report 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 issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.