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 29F65C38142 for ; Tue, 24 Jan 2023 16:29:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234383AbjAXQ35 (ORCPT ); Tue, 24 Jan 2023 11:29:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234015AbjAXQ3v (ORCPT ); Tue, 24 Jan 2023 11:29:51 -0500 Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C18959D3 for ; Tue, 24 Jan 2023 08:29:47 -0800 (PST) Received: by mail-ej1-x62a.google.com with SMTP id hw16so40423775ejc.10 for ; Tue, 24 Jan 2023 08:29:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=BOTYemAdqciiYIvAqJE2GsTaqj5FuuO8ZTKcaekuk6M=; b=RuATYPMe1mCqWxlvPqCHDER7+kVtKUI+JIrDt43qJiD0THXUgWMffDPQlpUhbBDtVj ekd+or4fJfbWSWxzXtD7KGptV8+wQOKUbiVR0/2i3C2j2Lf/PVhGH0QP8ckwLjbnSYTj 3u+aF23pkd2SEZFEjRz2uqeBksVizdklbX9AQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=BOTYemAdqciiYIvAqJE2GsTaqj5FuuO8ZTKcaekuk6M=; b=XsBk4xqIrkqf2OF1+SBgoHpUacmuyI8rB5g8sZ7awox+TGrEFi7l9yNIQI8NFj7HV4 baAkrHWIpKGnUI9v37Xs/OlmmrdGJ9R0jn5opWJvk56qA/li/hLvbKBTzgcjkFpOrnQu x4jp4Q3tdWYHt8BI17aOlTfImhcWNP64nbLERnbh5I1CkP5pWA050Gmj0Ssgc8qUyX1C hE+Jw+YmDOqyUGdgr9+/qdNdvOMK/4zniFkmQOcLW36UgMh3wUYQNRjRVk7pDVz5bX7b xD4IhIhBD3kVioVbAGdh/lsq/zImyZEk+7/WdT9ocqbxXBoQH66XTCnA//+AfOK8Li0E Zp+g== X-Gm-Message-State: AFqh2krXkunGLjLVeCN00mnn0G1+gqCxtm1fitDTOhHmBAdSP71YgYzN O6CtwCI8O0HYhBKwXS1nFoBNjlvYSmriOh9oG88V9g== X-Google-Smtp-Source: AMrXdXucss0qGqNGdTo8WigLjsv5u9qE4+RJ9x3z/jYYFnG3BCPhoYVnjt7Dmi0xU6rO4SEElM2pw6Qp/DEoe8Uq+8A= X-Received: by 2002:a17:907:9620:b0:7c1:10b4:4741 with SMTP id gb32-20020a170907962000b007c110b44741mr2881422ejc.8.1674577786060; Tue, 24 Jan 2023 08:29:46 -0800 (PST) MIME-Version: 1.0 References: <000000000000bac7df05f260d220@google.com> In-Reply-To: <000000000000bac7df05f260d220@google.com> From: Miklos Szeredi Date: Tue, 24 Jan 2023 17:29:35 +0100 Message-ID: Subject: Re: [syzbot] KASAN: use-after-free Read in fuse_dev_poll To: Jens Axboe Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, syzbot , io-uring@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hi Jens, Forwarding, since it looks like io_uring is the culprit: vfs_poll() is called by io_poll_check_events() on an already released file. Thanks, Miklos On Mon, 16 Jan 2023 at 13:35, 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=1485ee86480000 > kernel config: https://syzkaller.appspot.com/x/.config?x=835f3591019836d5 > dashboard link: https://syzkaller.appspot.com/bug?extid=d3b704fabd7f02206294 > 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. > > 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+d3b704fabd7f02206294@syzkaller.appspotmail.com > > ================================================================== > BUG: KASAN: use-after-free in fuse_dev_poll+0x1fe/0x240 fs/fuse/dev.c:2066 > Read of size 8 at addr ffff8880185fc500 by task syz-executor.4/7813 > > CPU: 0 PID: 7813 Comm: syz-executor.4 Not tainted 6.2.0-rc3-next-20230112-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 > 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 > fuse_dev_poll+0x1fe/0x240 fs/fuse/dev.c:2066 > vfs_poll include/linux/poll.h:88 [inline] > io_poll_check_events io_uring/poll.c:279 [inline] > io_poll_task_func+0x3a6/0x1220 io_uring/poll.c:327 > handle_tw_list+0xa8/0x460 io_uring/io_uring.c:1169 > tctx_task_work+0x12e/0x530 io_uring/io_uring.c:1224 > task_work_run+0x16f/0x270 kernel/task_work.c:179 > get_signal+0x1c7/0x24f0 kernel/signal.c:2635 > 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 > RIP: 0033:0x7f5c53a8c0c9 > Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007f5c5481c218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca > RAX: fffffffffffffe00 RBX: 00007f5c53babf88 RCX: 00007f5c53a8c0c9 > RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5c53babf88 > RBP: 00007f5c53babf80 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5c53babf8c > R13: 00007fff46acb32f R14: 00007f5c5481c300 R15: 0000000000022000 > > > Allocated by task 7813: > kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 > kasan_set_track+0x25/0x30 mm/kasan/common.c:52 > ____kasan_kmalloc mm/kasan/common.c:371 [inline] > ____kasan_kmalloc mm/kasan/common.c:330 [inline] > __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:380 > kmalloc include/linux/slab.h:580 [inline] > kzalloc include/linux/slab.h:720 [inline] > fuse_dev_alloc+0x48/0x270 fs/fuse/inode.c:1336 > fuse_dev_alloc_install fs/fuse/inode.c:1366 [inline] > fuse_fill_super_common+0x472/0x10b0 fs/fuse/inode.c:1558 > fuse_fill_super+0x1fb/0x2e0 fs/fuse/inode.c:1641 > vfs_get_super+0xea/0x280 fs/super.c:1128 > fuse_get_tree+0x277/0x640 fs/fuse/inode.c:1716 > vfs_get_tree+0x8d/0x2f0 fs/super.c:1489 > do_new_mount fs/namespace.c:3145 [inline] > path_mount+0x132a/0x1e20 fs/namespace.c:3475 > do_mount fs/namespace.c:3488 [inline] > __do_sys_mount fs/namespace.c:3697 [inline] > __se_sys_mount fs/namespace.c:3674 [inline] > __x64_sys_mount+0x283/0x300 fs/namespace.c:3674 > 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 7807: > 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+0xaf/0x2d0 mm/slub.c:3800 > fuse_dev_release+0x2ac/0x3f0 fs/fuse/dev.c:2220 > __fput+0x27c/0xa90 fs/file_table.c:321 > task_work_run+0x16f/0x270 kernel/task_work.c:179 > resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] > exit_to_user_mode_loop kernel/entry/common.c:171 [inline] > exit_to_user_mode_prepare+0x210/0x240 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 > > Last potentially related work creation: > kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 > __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488 > kvfree_call_rcu+0x70/0xad0 kernel/rcu/tree.c:3315 > kernfs_unlink_open_file+0x3a4/0x4a0 fs/kernfs/file.c:633 > kernfs_fop_release+0xeb/0x1e0 fs/kernfs/file.c:805 > __fput+0x27c/0xa90 fs/file_table.c:321 > task_work_run+0x16f/0x270 kernel/task_work.c:179 > resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] > exit_to_user_mode_loop kernel/entry/common.c:171 [inline] > exit_to_user_mode_prepare+0x210/0x240 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 > > Second to last potentially related work creation: > kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 > __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488 > kvfree_call_rcu+0x70/0xad0 kernel/rcu/tree.c:3315 > kernfs_unlink_open_file+0x3a4/0x4a0 fs/kernfs/file.c:633 > kernfs_fop_release+0xeb/0x1e0 fs/kernfs/file.c:805 > __fput+0x27c/0xa90 fs/file_table.c:321 > task_work_run+0x16f/0x270 kernel/task_work.c:179 > resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] > exit_to_user_mode_loop kernel/entry/common.c:171 [inline] > exit_to_user_mode_prepare+0x210/0x240 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 > > The buggy address belongs to the object at ffff8880185fc500 > which belongs to the cache kmalloc-128 of size 128 > The buggy address is located 0 bytes inside of > 128-byte region [ffff8880185fc500, ffff8880185fc580) > > The buggy address belongs to the physical page: > page:ffffea0000617f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880185fc700 pfn:0x185fc > anon flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) > raw: 00fff00000000200 ffff8880124418c0 0000000000000000 dead000000000001 > raw: ffff8880185fc700 000000008010000e 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5935, tgid 5934 (syz-executor.0), ts 311717359180, free_ts 231319442393 > 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 > __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 > __slab_alloc_node mm/slub.c:3345 [inline] > slab_alloc_node mm/slub.c:3442 [inline] > __kmem_cache_alloc_node+0x136/0x330 mm/slub.c:3491 > __do_kmalloc_node mm/slab_common.c:966 [inline] > __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:987 > kmemdup+0x2c/0x60 mm/util.c:130 > kmemdup include/linux/fortify-string.h:702 [inline] > mpls_dev_sysctl_register+0xaa/0x2d0 net/mpls/af_mpls.c:1406 > mpls_add_dev net/mpls/af_mpls.c:1472 [inline] > mpls_dev_notify+0x46d/0x990 net/mpls/af_mpls.c:1612 > notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 > call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1944 > call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] > call_netdevice_notifiers net/core/dev.c:1996 [inline] > register_netdevice+0xfb4/0x1640 net/core/dev.c:10078 > __ip_tunnel_create+0x398/0x570 net/ipv4/ip_tunnel.c:267 > ip_tunnel_init_net+0x1f9/0x5a0 net/ipv4/ip_tunnel.c:1073 > 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 > vm_area_alloc+0x20/0x100 kernel/fork.c:458 > mmap_region+0x44c/0x1e50 mm/mmap.c:2605 > do_mmap+0x831/0xf60 mm/mmap.c:1411 > vm_mmap_pgoff+0x1af/0x280 mm/util.c:542 > ksys_mmap_pgoff+0x41f/0x5a0 mm/mmap.c:1457 > 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 > > Memory state around the buggy address: > ffff8880185fc400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffff8880185fc480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > >ffff8880185fc500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8880185fc580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff8880185fc600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== > > > --- > 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.