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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B19E0C67861 for ; Fri, 5 Apr 2024 18:09:50 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 311996B009F; Fri, 5 Apr 2024 14:09:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 29AB16B00A0; Fri, 5 Apr 2024 14:09:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 13B896B00A1; Fri, 5 Apr 2024 14:09:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id E8AB26B009F for ; Fri, 5 Apr 2024 14:09:49 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id AA1DE1C1113 for ; Fri, 5 Apr 2024 18:09:49 +0000 (UTC) X-FDA: 81976266498.27.88645CD Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf19.hostedemail.com (Postfix) with ESMTP id 7D3241A001F for ; Fri, 5 Apr 2024 18:09:46 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="U7Qk3/eF"; spf=pass (imf19.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1712340588; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=lbD0VVEMfiB+u0vP/GBw83Gf/WLJQ2JTMycx7HRYv5Y=; b=ir7uSkEbPPog8mLZPQ+nafRnIu72IyHNCaUBnFd6xFK/o0sVer5CatFB87N6ErcHPYtwS7 jYLm4MZZTA8pqUSh2lr0X6Wrc0PNCL+1dzVb48xY7NAszSRhLWXeKfVHpsDIvl4l9utmmJ PXQdt11OTZQKEUek57mRyMS8CBBbUBU= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1712340588; a=rsa-sha256; cv=none; b=zUeXal/qi/qDEaESKz9lnENTtMEmxzVgm9ArNMilIZsuCTjIJjFkv76BhaxBnwhNKnwzxI 690Lvwsdyoi9wvsgf2D9tJU3AewGOGBYfoDr25vPla/pyGGzUX8AP593/sytbLm+HWPYNL leB7J2gMRPTgqf01keQ9sZPP1o6GzRk= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="U7Qk3/eF"; spf=pass (imf19.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id BCF89CE2568; Fri, 5 Apr 2024 18:09:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CE36C43394; Fri, 5 Apr 2024 18:09:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1712340581; bh=XEHM2bscJ15DcdykoH5CPf8wc/c3cOkcZOvvQc5/ays=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=U7Qk3/eF8troLYxOnlAkKqT5spZJXknJ4Kdz0KmA5i3nJCXaiL64ZWV+P7fkSqwCV uhe7F58Wd1bl46TTfl9KmywmUlMhxxsc59/t8RpPqOAwOyO6PI6txR20+3bTq8IjDR ncECEXJGZY2zrDFrPlRY8k3RlDiBFo26mF3TnUvY= Date: Fri, 5 Apr 2024 11:09:40 -0700 From: Andrew Morton To: syzbot Cc: gustavoars@kernel.org, keescook@chromium.org, linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, Aneesh Kumar Subject: Re: [syzbot] [mm?] [hardening?] BUG: bad usercopy in do_handle_open Message-Id: <20240405110940.e787791b7d53aff7f216a168@linux-foundation.org> In-Reply-To: <000000000000b8974d06155cf3a2@google.com> References: <000000000000b8974d06155cf3a2@google.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: 3i6k3hwwu1xbryd4w4qr57fooeom8jew X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 7D3241A001F X-Rspam-User: X-HE-Tag: 1712340586-134520 X-HE-Meta: U2FsdGVkX1+FkN+4It7M2OhoTTOEsQ7DlKPjMObyM4/UBssTfwOLFAFvAkJh1Qihwt7ugwFlGnFlF4alxir9FYvqrgDxLtrW0Tv1RYFoQoCDGaOYyaQSK/mHu48KRO9VV19S6y/0mbPLbJ0IfEmwTmClJWnJh2+EOhspPO3kT/Ny8q4LyKRAa+rxEd/IM9BgQymRS5jGhOJrn13cn5+YppqY7FlEq4eh2+EL3JoMM45u7rbZ2pEP1XaSHa+3EwEEGPKERFcIqk6PYieB5pflSXJ8Udi7vGQJFoVElr2E1C8nZbNYw/FFQWWWeJ5WjVsdgS7ywOPoTWVMZE3KIumwV+pvgggoT7mlE0gfBAG+DjgkGqGWn8C8zCb3C7DRm5loZ7v0snvxYtDXL6KdTaVsNyCADs1oLrSqUIxf+TkFKAVHmA5unLQ/+SbAKq5vzrsnOW9SYV2+N8WcG/kNnuWI+x1N7/kfihjQnkxCynNVxcr983we2EKkbrSlqds9gbsPcMVv9m1jQND30WOCbxyJ0YhVzYBBxLyWMhF+HMMiQUqJXncwqkk6MBcaDXcvyNoERm7Y4H8D8/SkBqRL+fcVY/NdyMC59qIaCkCYzRSA1IFH8XVuRsT92uhpy7J3rvRD6movZjw/B+6H+3LzwymlXJJUyfkiI8qmC/KOAby6WJngOi4DnKQxK3S1rcW3pktnHcflaJYeCFdpq7k+RRIB8pCeGi2C4h5W8fViz1kshanJTlzYsPLNotV4H/WAdQ5SpfUGg5N1UExorm5YYloKEVBGku3hpGj+RXdMH3SnOB8e8T5qA0RaahgBlRW4+NHoSzCDFWb1+p2aVKowK7yMo81ExI8lIDq1asaFz4oF64QQbeQhTnfvntrRLjq4jPTYzukcdZlZgX28t6R6dnAI1IO1/YR2xgNkaqzIZBzw5rwG8IxDAnxQxreNP47F8sVJoKJx448w5aP1SkH8DA6 vc8Z9Ehz bCRgIWcm7MnEtZoWGPArtSyQkIEAl04SqkSOdIJR75rlmHuJ0WYHrFIj6uQxLajxMxMfmMuEBZxZVG7ipc18uSZdsNmnerq4NBYxQivrV+duTvu+8iCDa7nhLPDzhoxv0PPr1PNPfMi6yeNqIFXVZp9bckkQoTX5x0op09/XJVvF0km184zswpX/0ClUdEPJrBFuFA9rYtiWJuB9QVhZgK1FmMYpPY5+PauTKPsoc5UQvSBnYZ+9ZCcZkvmmJpx8L0rM8ld/i81GG6SXAffsd6ORi9b4CaUD6WlJaoYkvcLSpe79dyDCt/40o1Nakf9Ddrk8XrgzDwN4fAoyXkVHpnebRqQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, 05 Apr 2024 10:40:30 -0700 syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: c0b832517f62 Add linux-next specific files for 20240402 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=13a5c3b1180000 > kernel config: https://syzkaller.appspot.com/x/.config?x=afcaf46d374cec8c > dashboard link: https://syzkaller.appspot.com/bug?extid=4372e026c95b0e36d0ee > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16ed9d29180000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=161ab3c6180000 I'd be suspecting the bounds checking in handle_to_path(), but it looks solid to me. > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/0d36ec76edc7/disk-c0b83251.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/6f9bb4e37dd0/vmlinux-c0b83251.xz > kernel image: https://storage.googleapis.com/syzbot-assets/2349287b14b7/bzImage-c0b83251.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+4372e026c95b0e36d0ee@syzkaller.appspotmail.com > > usercopy: Kernel memory overwrite attempt detected to SLUB object 'kmalloc-16' (offset 8, size 9)! We tried to copy 9 bytes into the f_handle[] array. But from my reading of the reproducer, f_handle.handle_bytes was set to 1. Aneesh, any thoughts on this? > ------------[ cut here ]------------ > kernel BUG at mm/usercopy.c:102! > Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI > CPU: 1 PID: 5081 Comm: syz-executor249 Not tainted 6.9.0-rc2-next-20240402-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 > RIP: 0010:usercopy_abort+0x84/0x90 mm/usercopy.c:102 > Code: 49 89 ce 48 c7 c3 e0 27 d8 8b 48 0f 44 de 48 c7 c7 80 26 d8 8b 4c 89 de 48 89 c1 41 52 41 56 53 e8 b1 6f 75 09 48 83 c4 18 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 > RSP: 0018:ffffc90003dbfd78 EFLAGS: 00010286 > RAX: 0000000000000062 RBX: ffffffff8bd827e0 RCX: 2b2ecef8eabe4800 > RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 > RBP: 0000000000000008 R08: ffffffff81760b9c R09: 1ffff920007b7f4c > R10: dffffc0000000000 R11: fffff520007b7f4d R12: ffffea00008fe840 > R13: 0000000000000009 R14: 0000000000000008 R15: 0000000000000009 > FS: 000055556aa78380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000040 CR3: 0000000076e74000 CR4: 00000000003506f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > > __check_heap_object+0xb1/0x100 mm/slub.c:5461 > check_heap_object mm/usercopy.c:196 [inline] > __check_object_size+0x1e3/0x900 mm/usercopy.c:251 > check_object_size include/linux/thread_info.h:215 [inline] > check_copy_size include/linux/thread_info.h:251 [inline] > copy_from_user include/linux/uaccess.h:182 [inline] > handle_to_path fs/fhandle.c:203 [inline] > do_handle_open+0x1f6/0x660 fs/fhandle.c:226 > do_syscall_64+0xfb/0x240 > entry_SYSCALL_64_after_hwframe+0x72/0x7a > RIP: 0033:0x7f27665352a9 > Code: 48 83 c4 28 c3 e8 37 17 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007ffe7e4589d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000130 > RAX: ffffffffffffffda RBX: 00007ffe7e458bb8 RCX: 00007f27665352a9 > RDX: 0000000000000000 RSI: 0000000020000040 RDI: 00000000ffffffff > RBP: 00007f27665a8610 R08: 0000000000000000 R09: 0000000000000000 > R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000001 > R13: 00007ffe7e458ba8 R14: 0000000000000001 R15: 0000000000000001 > > Modules linked in: > ---[ end trace 0000000000000000 ]--- > RIP: 0010:usercopy_abort+0x84/0x90 mm/usercopy.c:102 > Code: 49 89 ce 48 c7 c3 e0 27 d8 8b 48 0f 44 de 48 c7 c7 80 26 d8 8b 4c 89 de 48 89 c1 41 52 41 56 53 e8 b1 6f 75 09 48 83 c4 18 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 > RSP: 0018:ffffc90003dbfd78 EFLAGS: 00010286 > RAX: 0000000000000062 RBX: ffffffff8bd827e0 RCX: 2b2ecef8eabe4800 > RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 > RBP: 0000000000000008 R08: ffffffff81760b9c R09: 1ffff920007b7f4c > R10: dffffc0000000000 R11: fffff520007b7f4d R12: ffffea00008fe840 > R13: 0000000000000009 R14: 0000000000000008 R15: 0000000000000009 > FS: 000055556aa78380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000040 CR3: 0000000076e74000 CR4: 00000000003506f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > --- > 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. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup