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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D8E3C61DB3 for ; Thu, 12 Jan 2023 10:44:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233956AbjALKoQ (ORCPT ); Thu, 12 Jan 2023 05:44:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43286 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230509AbjALKnS (ORCPT ); Thu, 12 Jan 2023 05:43:18 -0500 Received: from mail-il1-f200.google.com (mail-il1-f200.google.com [209.85.166.200]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2898652C73 for ; Thu, 12 Jan 2023 02:38:51 -0800 (PST) Received: by mail-il1-f200.google.com with SMTP id z19-20020a921a53000000b0030b90211df1so12926928ill.2 for ; Thu, 12 Jan 2023 02:38:51 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=OC4LA1cA+kPrcLUJOJ6pcEADWhFB3YivjRWdVGPG9as=; b=pynSx9Ir3AXl2tLybr3ajVpWlW13GPqhkDIQqpFujpfKZNZBd/E4BxURz5cx4kWVRu gVCz6t5kY/+krezAbjUUQty2vmdUtCg9Z4iyeF2aSOT2MiAFH8WEP3fMlcq/O0/1qRQ3 WJ/0h/9sw0yIx6SeqfgxMF4f9G3NpOnD7iMBxIBzvnNJkMcDGQgfTUyMFcKNdTsAdWue HTD8EfUQCCuXqIVGf5SU4SLEAzqfUpksFmgENOMxOkAfrnyLncno/twIxVye4AfIIg9e DyLj+rXZyHUfQXT58i6nomVoAlyiorNxQmD4PNInFW+EPseRBgBnu7sxnf4e1Ii93WK6 WPhA== X-Gm-Message-State: AFqh2kqsf1r1AUNrihhrlJUk4WpgID0m1pslFHLhowXZyXr640krnbr+ yuJvxxuehJkLnpJJ78H2vCSodLdQPlmFjQBC64Whlp5PCw3b X-Google-Smtp-Source: AMrXdXv9YbV4euO+Hc4HOffnZ+FlkmtDMpe8DPVcuOUfImoQdmw5278/SA/qIB9XxOPKNV++DUqtcwtWwufWZueB1MtBuctjG6jN MIME-Version: 1.0 X-Received: by 2002:a5d:88ce:0:b0:6e2:fb39:a5d4 with SMTP id i14-20020a5d88ce000000b006e2fb39a5d4mr7372686iol.45.1673519930505; Thu, 12 Jan 2023 02:38:50 -0800 (PST) Date: Thu, 12 Jan 2023 02:38:50 -0800 In-Reply-To: <3f4c1d69-cca2-ee6a-55e0-95028cf739da@gmail.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000fb82de05f20eb8e8@google.com> Subject: Re: [syzbot] KASAN: use-after-free Read in io_fallback_req_func From: syzbot To: asml.silence@gmail.com Cc: asml.silence@gmail.com, axboe@kernel.dk, io-uring@vger.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: io-uring@vger.kernel.org > On 1/12/23 10:09, syzbot wrote: >> Hello, >> >> syzbot found the following issue on: >> >> HEAD commit: 0a093b2893c7 Add linux-next specific files for 20230112 >> git tree: linux-next >> console output: https://syzkaller.appspot.com/x/log.txt?x=103269ce480000 >> kernel config: https://syzkaller.appspot.com/x/.config?x=835f3591019836d5 >> dashboard link: https://syzkaller.appspot.com/bug?extid=bc022c162e3b001bf607 >> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 >> >> Unfortunately, I don't have any reproducer for this issue yet. > > #syz test: git://git.kernel.dk/linux.git syztest This crash does not have a reproducer. I cannot test it. > >> >> Downloadable assets: >> disk image: https://storage.googleapis.com/syzbot-assets/8111a570d6cb/disk-0a093b28.raw.xz >> vmlinux: https://storage.googleapis.com/syzbot-assets/ecc135b7fc9a/vmlinux-0a093b28.xz >> kernel image: https://storage.googleapis.com/syzbot-assets/ca8d73b446ea/bzImage-0a093b28.xz >> >> IMPORTANT: if you fix the issue, please add the following tag to the commit: >> Reported-by: syzbot+bc022c162e3b001bf607@syzkaller.appspotmail.com >> >> ================================================================== >> BUG: KASAN: use-after-free in io_fallback_req_func+0xc7/0x204 io_uring/io_uring.c:251 >> Read of size 8 at addr ffff888070ac2e48 by task kworker/0:0/7 >> >> CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted 6.2.0-rc3-next-20230112-syzkaller #0 >> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 >> Workqueue: events io_fallback_req_func >> Call Trace: >> >> __dump_stack lib/dump_stack.c:88 [inline] >> dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 >> print_address_description mm/kasan/report.c:306 [inline] >> print_report+0x15e/0x45d mm/kasan/report.c:417 >> kasan_report+0xc0/0xf0 mm/kasan/report.c:517 >> io_fallback_req_func+0xc7/0x204 io_uring/io_uring.c:251 >> process_one_work+0x9bf/0x1750 kernel/workqueue.c:2293 >> worker_thread+0x669/0x1090 kernel/workqueue.c:2440 >> kthread+0x2e8/0x3a0 kernel/kthread.c:376 >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 >> >> >> Allocated by task 7766: >> kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 >> kasan_set_track+0x25/0x30 mm/kasan/common.c:52 >> __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:325 >> kasan_slab_alloc include/linux/kasan.h:186 [inline] >> slab_post_alloc_hook mm/slab.h:769 [inline] >> kmem_cache_alloc_bulk+0x3aa/0x730 mm/slub.c:4033 >> __io_alloc_req_refill+0xcc/0x40b io_uring/io_uring.c:1062 >> io_alloc_req_refill io_uring/io_uring.h:348 [inline] >> io_submit_sqes.cold+0x7c/0xc2 io_uring/io_uring.c:2407 >> __do_sys_io_uring_enter+0x9e4/0x2c10 io_uring/io_uring.c:3429 >> do_syscall_x64 arch/x86/entry/common.c:50 [inline] >> do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 >> entry_SYSCALL_64_after_hwframe+0x63/0xcd >> >> Freed by task 5179: >> kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 >> kasan_set_track+0x25/0x30 mm/kasan/common.c:52 >> kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:518 >> ____kasan_slab_free mm/kasan/common.c:236 [inline] >> ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 >> kasan_slab_free include/linux/kasan.h:162 [inline] >> slab_free_hook mm/slub.c:1781 [inline] >> slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 >> slab_free mm/slub.c:3787 [inline] >> kmem_cache_free+0xec/0x4e0 mm/slub.c:3809 >> io_req_caches_free+0x1a9/0x1e6 io_uring/io_uring.c:2737 >> io_ring_exit_work+0x2e7/0xc80 io_uring/io_uring.c:2967 >> process_one_work+0x9bf/0x1750 kernel/workqueue.c:2293 >> worker_thread+0x669/0x1090 kernel/workqueue.c:2440 >> kthread+0x2e8/0x3a0 kernel/kthread.c:376 >> ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 >> >> The buggy address belongs to the object at ffff888070ac2dc0 >> which belongs to the cache io_kiocb of size 216 >> The buggy address is located 136 bytes inside of >> 216-byte region [ffff888070ac2dc0, ffff888070ac2e98) >> >> The buggy address belongs to the physical page: >> page:ffffea0001c2b080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x70ac2 >> memcg:ffff88802a81d181 >> flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) >> raw: 00fff00000000200 ffff8881461d1780 dead000000000122 0000000000000000 >> raw: 0000000000000000 00000000800c000c 00000001ffffffff ffff88802a81d181 >> page dumped because: kasan: bad access detected >> page_owner tracks the page as allocated >> page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5547, tgid 5545 (syz-executor.4), ts 182131630120, free_ts 181898498774 >> prep_new_page mm/page_alloc.c:2549 [inline] >> get_page_from_freelist+0x11bb/0x2d50 mm/page_alloc.c:4324 >> __alloc_pages+0x1cb/0x5c0 mm/page_alloc.c:5590 >> alloc_pages+0x1aa/0x270 mm/mempolicy.c:2281 >> alloc_slab_page mm/slub.c:1851 [inline] >> allocate_slab+0x25f/0x350 mm/slub.c:1998 >> new_slab mm/slub.c:2051 [inline] >> ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 >> __kmem_cache_alloc_bulk mm/slub.c:3951 [inline] >> kmem_cache_alloc_bulk+0x23d/0x730 mm/slub.c:4026 >> __io_alloc_req_refill+0xcc/0x40b io_uring/io_uring.c:1062 >> io_alloc_req_refill io_uring/io_uring.h:348 [inline] >> io_submit_sqes.cold+0x7c/0xc2 io_uring/io_uring.c:2407 >> __do_sys_io_uring_enter+0x9e4/0x2c10 io_uring/io_uring.c:3429 >> do_syscall_x64 arch/x86/entry/common.c:50 [inline] >> do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 >> entry_SYSCALL_64_after_hwframe+0x63/0xcd >> page last free stack trace: >> reset_page_owner include/linux/page_owner.h:24 [inline] >> free_pages_prepare mm/page_alloc.c:1451 [inline] >> free_pcp_prepare+0x4d0/0x910 mm/page_alloc.c:1501 >> free_unref_page_prepare mm/page_alloc.c:3387 [inline] >> free_unref_page+0x1d/0x490 mm/page_alloc.c:3482 >> qlink_free mm/kasan/quarantine.c:168 [inline] >> qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 >> kasan_quarantine_reduce+0x192/0x220 mm/kasan/quarantine.c:294 >> __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:302 >> kasan_slab_alloc include/linux/kasan.h:186 [inline] >> slab_post_alloc_hook mm/slab.h:769 [inline] >> slab_alloc_node mm/slub.c:3452 [inline] >> slab_alloc mm/slub.c:3460 [inline] >> __kmem_cache_alloc_lru mm/slub.c:3467 [inline] >> kmem_cache_alloc+0x175/0x320 mm/slub.c:3476 >> kmem_cache_zalloc include/linux/slab.h:710 [inline] >> taskstats_tgid_alloc kernel/taskstats.c:583 [inline] >> taskstats_exit+0x5f3/0xb80 kernel/taskstats.c:622 >> do_exit+0x822/0x2a90 kernel/exit.c:852 >> do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 >> get_signal+0x225f/0x24f0 kernel/signal.c:2859 >> arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 >> exit_to_user_mode_loop kernel/entry/common.c:168 [inline] >> exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 >> __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] >> syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 >> do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 >> entry_SYSCALL_64_after_hwframe+0x63/0xcd >> >> Memory state around the buggy address: >> ffff888070ac2d00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc >> ffff888070ac2d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >>> ffff888070ac2e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >> ^ >> ffff888070ac2e80: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc >> ffff888070ac2f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >> ================================================================== >> >> >> --- >> 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. > > -- > Pavel Begunkov