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=-3.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 CE385C388F7 for ; Mon, 9 Nov 2020 18:06:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7024420663 for ; Mon, 9 Nov 2020 18:06:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730092AbgKISGT (ORCPT ); Mon, 9 Nov 2020 13:06:19 -0500 Received: from mail-io1-f71.google.com ([209.85.166.71]:39501 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729119AbgKISGT (ORCPT ); Mon, 9 Nov 2020 13:06:19 -0500 Received: by mail-io1-f71.google.com with SMTP id z18so6277179ioz.6 for ; Mon, 09 Nov 2020 10:06:17 -0800 (PST) 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=oGJS1xcLVmjeSr0kicAZZo67XlZTQ7FFIBD2yf36yuM=; b=d/s1QKU19Ml4Av53CiOBygW03AnWZveqWPWizF/Vx+HWjg7cCgC6Ecj2XupXR8upgE u0UvcEESEhy7WCAgMSOCi7Gfp1ByjluB5OnfxEWWEfea+GWTelc/V6b95KdDxgTMVnJd XeYs0e6clsu9FXsqXtR66xbkDW3BJ4RX9aQvaJPFt4XGqzAWPpzB0V3T2IiRdVsVb1GD s/qe/V9DpnumELx71WsVVuwJW3WiJxfRE1ba6K4twveFBs/rmiVkCMifltPTawfnjYcN WDuVPsWMI2ejaaNndeo6oKTjaNPYOllFGURiDHq6I6yfe+AqFn2/l66Aiq7nTeSVw1Dl FneQ== X-Gm-Message-State: AOAM530K9cTUDYCwmMzERKB/Vci2CweP6jBDQ86HFoAMVlAsRi3/R1ZT zundZ6r74bjKQh99MrXriV6xxZTvlrHK6svdlpTSld6p0So8 X-Google-Smtp-Source: ABdhPJyVypA3dVFfLAgJSp/DnCjQIjz/xAskbEUiidyvXvz61uB3Hp4Wi8QNgwrHaNSfAFhTJo4FCrDRdW8wj531OCFtAoF5FTHC MIME-Version: 1.0 X-Received: by 2002:a02:9716:: with SMTP id x22mr11524563jai.114.1604945176955; Mon, 09 Nov 2020 10:06:16 -0800 (PST) Date: Mon, 09 Nov 2020 10:06:16 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000028115c05b3b06bbd@google.com> Subject: KASAN: slab-out-of-bounds Read in io_uring_show_cred From: syzbot To: axboe@kernel.dk, io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: cf7cd542 Add linux-next specific files for 20201104 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=14649314500000 kernel config: https://syzkaller.appspot.com/x/.config?x=e8dc0c5ac73afb92 dashboard link: https://syzkaller.appspot.com/bug?extid=46061b9b42fecc6e7d6d compiler: gcc (GCC) 10.1.0-syz 20200507 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+46061b9b42fecc6e7d6d@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-out-of-bounds in io_uring_show_cred+0x598/0x5f0 fs/io_uring.c:9225 Read of size 4 at addr ffff8880253d13c8 by task syz-executor.3/10456 CPU: 1 PID: 10456 Comm: syz-executor.3 Not tainted 5.10.0-rc2-next-20201104-syzkaller #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+0x107/0x163 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x4c8 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562 io_uring_show_cred+0x598/0x5f0 fs/io_uring.c:9225 idr_for_each+0x113/0x220 lib/idr.c:208 __io_uring_show_fdinfo fs/io_uring.c:9272 [inline] io_uring_show_fdinfo+0x923/0xda0 fs/io_uring.c:9294 seq_show+0x4a8/0x700 fs/proc/fd.c:65 seq_read+0x432/0x1070 fs/seq_file.c:208 do_loop_readv_writev fs/read_write.c:761 [inline] do_loop_readv_writev fs/read_write.c:748 [inline] do_iter_read+0x48e/0x6e0 fs/read_write.c:803 vfs_readv+0xe5/0x150 fs/read_write.c:921 do_preadv fs/read_write.c:1013 [inline] __do_sys_preadv fs/read_write.c:1063 [inline] __se_sys_preadv fs/read_write.c:1058 [inline] __x64_sys_preadv+0x231/0x310 fs/read_write.c:1058 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45deb9 Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f691c7eac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 0000000000025e40 RCX: 000000000045deb9 RDX: 0000000000000333 RSI: 00000000200017c0 RDI: 0000000000000005 RBP: 000000000118c018 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bfd4 R13: 00007ffef15d676f R14: 00007f691c7eb9c0 R15: 000000000118bfd4 Allocated by task 10448: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461 kmalloc include/linux/slab.h:552 [inline] io_register_personality fs/io_uring.c:9647 [inline] __io_uring_register fs/io_uring.c:9883 [inline] __do_sys_io_uring_register+0x10f0/0x40a0 fs/io_uring.c:9933 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8880253d1380 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 72 bytes inside of 96-byte region [ffff8880253d1380, ffff8880253d13e0) The buggy address belongs to the page: page:000000003c207268 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x253d1 flags: 0xfff00000000200(slab) raw: 00fff00000000200 ffffea0000a900c0 0000000500000005 ffff888010041780 raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880253d1280: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff8880253d1300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8880253d1380: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ^ ffff8880253d1400: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff8880253d1480: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. 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