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 10D5FEB64D7 for ; Mon, 26 Jun 2023 23:27:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229715AbjFZX1L (ORCPT ); Mon, 26 Jun 2023 19:27:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59446 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229488AbjFZX1K (ORCPT ); Mon, 26 Jun 2023 19:27:10 -0400 Received: from mail-io1-f79.google.com (mail-io1-f79.google.com [209.85.166.79]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC2D21991 for ; Mon, 26 Jun 2023 16:27:06 -0700 (PDT) Received: by mail-io1-f79.google.com with SMTP id ca18e2360f4ac-77ac4aa24eeso246577539f.1 for ; Mon, 26 Jun 2023 16:27:06 -0700 (PDT) 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w190-20020a022ac7000000b0041ac455f4c8mr10603429jaw.3.1687822026138; Mon, 26 Jun 2023 16:27:06 -0700 (PDT) Date: Mon, 26 Jun 2023 16:27:06 -0700 In-Reply-To: <000000000000d0021505f0522813@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000004fea4805ff10b0a5@google.com> Subject: Re: [syzbot] [reiserfs?] possible deadlock in page_cache_ra_unbounded From: syzbot To: akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, reiserfs-devel@vger.kernel.org, syzkaller-bugs@googlegroups.com, willy@infradead.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org syzbot has found a reproducer for the following issue on: HEAD commit: c0a572d9d32f Merge tag 'v6.5/vfs.mount' of git://git.kerne.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=11d54c0b280000 kernel config: https://syzkaller.appspot.com/x/.config?x=f4df35260418daa6 dashboard link: https://syzkaller.appspot.com/bug?extid=47c7e14e1bd09234d0ad compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11c01f00a80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=145add7b280000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/1855f91c7ed0/disk-c0a572d9.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/fbbea26cfe51/vmlinux-c0a572d9.xz kernel image: https://storage.googleapis.com/syzbot-assets/5c9ca7f2d7aa/bzImage-c0a572d9.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/d0602a911ff3/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+47c7e14e1bd09234d0ad@syzkaller.appspotmail.com REISERFS (device loop0): Using r5 hash to sort names REISERFS (device loop0): using 3.5.x disk format REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage. ====================================================== WARNING: possible circular locking dependency detected 6.4.0-syzkaller-00082-gc0a572d9d32f #0 Not tainted ------------------------------------------------------ syz-executor281/5085 is trying to acquire lock: ffff88807d74e090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x69/0xe0 fs/reiserfs/lock.c:78 but task is already holding lock: ffff888070c6e7e0 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:833 [inline] ffff888070c6e7e0 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: page_cache_ra_unbounded+0x153/0x5e0 mm/readahead.c:226 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (mapping.invalidate_lock#3){.+.+}-{3:3}: down_read+0x9c/0x480 kernel/locking/rwsem.c:1520 filemap_invalidate_lock_shared include/linux/fs.h:833 [inline] page_cache_ra_unbounded+0x153/0x5e0 mm/readahead.c:226 do_page_cache_ra mm/readahead.c:300 [inline] page_cache_ra_order+0x6ec/0xa00 mm/readahead.c:560 do_sync_mmap_readahead mm/filemap.c:3193 [inline] filemap_fault+0x1572/0x24c0 mm/filemap.c:3285 __do_fault+0x107/0x600 mm/memory.c:4176 do_shared_fault mm/memory.c:4585 [inline] do_fault mm/memory.c:4663 [inline] do_pte_missing mm/memory.c:3647 [inline] handle_pte_fault mm/memory.c:4947 [inline] __handle_mm_fault+0x24c9/0x41c0 mm/memory.c:5089 handle_mm_fault+0x2a7/0x9e0 mm/memory.c:5243 do_user_addr_fault+0x51a/0x1210 arch/x86/mm/fault.c:1440 handle_page_fault arch/x86/mm/fault.c:1534 [inline] exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 __put_user_4+0x11/0x20 arch/x86/lib/putuser.S:89 reiserfs_ioctl+0x20d/0x330 fs/reiserfs/ioctl.c:96 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x19d/0x210 fs/ioctl.c:856 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 -> #0 (&sbi->lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3113 [inline] check_prevs_add kernel/locking/lockdep.c:3232 [inline] validate_chain kernel/locking/lockdep.c:3847 [inline] __lock_acquire+0x2fcd/0x5f30 kernel/locking/lockdep.c:5088 lock_acquire kernel/locking/lockdep.c:5705 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747 reiserfs_write_lock_nested+0x69/0xe0 fs/reiserfs/lock.c:78 reiserfs_cond_resched fs/reiserfs/reiserfs.h:849 [inline] reiserfs_cond_resched fs/reiserfs/reiserfs.h:842 [inline] search_by_key+0x2452/0x3b60 fs/reiserfs/stree.c:712 search_for_position_by_key+0xcf/0x1180 fs/reiserfs/stree.c:874 _get_block_create_0+0x23f/0x1a70 fs/reiserfs/inode.c:305 reiserfs_get_block+0x244f/0x4100 fs/reiserfs/inode.c:695 do_mpage_readpage+0x768/0x1960 fs/mpage.c:234 mpage_readahead+0x344/0x580 fs/mpage.c:382 read_pages+0x1a2/0xd40 mm/readahead.c:161 page_cache_ra_unbounded+0x477/0x5e0 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] page_cache_ra_order+0x6ec/0xa00 mm/readahead.c:560 do_sync_mmap_readahead mm/filemap.c:3193 [inline] filemap_fault+0x1572/0x24c0 mm/filemap.c:3285 __do_fault+0x107/0x600 mm/memory.c:4176 do_shared_fault mm/memory.c:4585 [inline] do_fault mm/memory.c:4663 [inline] do_pte_missing mm/memory.c:3647 [inline] handle_pte_fault mm/memory.c:4947 [inline] __handle_mm_fault+0x24c9/0x41c0 mm/memory.c:5089 handle_mm_fault+0x2a7/0x9e0 mm/memory.c:5243 do_user_addr_fault+0x51a/0x1210 arch/x86/mm/fault.c:1440 handle_page_fault arch/x86/mm/fault.c:1534 [inline] exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 __put_user_4+0x11/0x20 arch/x86/lib/putuser.S:89 reiserfs_ioctl+0x20d/0x330 fs/reiserfs/ioctl.c:96 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x19d/0x210 fs/ioctl.c:856 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 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(mapping.invalidate_lock#3); lock(&sbi->lock); lock(mapping.invalidate_lock#3); lock(&sbi->lock); *** DEADLOCK *** 1 lock held by syz-executor281/5085: #0: ffff888070c6e7e0 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:833 [inline] #0: ffff888070c6e7e0 (mapping.invalidate_lock#3){.+.+}-{3:3}, at: page_cache_ra_unbounded+0x153/0x5e0 mm/readahead.c:226 stack backtrace: CPU: 1 PID: 5085 Comm: syz-executor281 Not tainted 6.4.0-syzkaller-00082-gc0a572d9d32f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2188 check_prev_add kernel/locking/lockdep.c:3113 [inline] check_prevs_add kernel/locking/lockdep.c:3232 [inline] validate_chain kernel/locking/lockdep.c:3847 [inline] __lock_acquire+0x2fcd/0x5f30 kernel/locking/lockdep.c:5088 lock_acquire kernel/locking/lockdep.c:5705 [inline] lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747 reiserfs_write_lock_nested+0x69/0xe0 fs/reiserfs/lock.c:78 reiserfs_cond_resched fs/reiserfs/reiserfs.h:849 [inline] reiserfs_cond_resched fs/reiserfs/reiserfs.h:842 [inline] search_by_key+0x2452/0x3b60 fs/reiserfs/stree.c:712 search_for_position_by_key+0xcf/0x1180 fs/reiserfs/stree.c:874 _get_block_create_0+0x23f/0x1a70 fs/reiserfs/inode.c:305 reiserfs_get_block+0x244f/0x4100 fs/reiserfs/inode.c:695 do_mpage_readpage+0x768/0x1960 fs/mpage.c:234 mpage_readahead+0x344/0x580 fs/mpage.c:382 read_pages+0x1a2/0xd40 mm/readahead.c:161 page_cache_ra_unbounded+0x477/0x5e0 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] page_cache_ra_order+0x6ec/0xa00 mm/readahead.c:560 do_sync_mmap_readahead mm/filemap.c:3193 [inline] filemap_fault+0x1572/0x24c0 mm/filemap.c:3285 __do_fault+0x107/0x600 mm/memory.c:4176 do_shared_fault mm/memory.c:4585 [inline] do_fault mm/memory.c:4663 [inline] do_pte_missing mm/memory.c:3647 [inline] handle_pte_fault mm/memory.c:4947 [inline] __handle_mm_fault+0x24c9/0x41c0 mm/memory.c:5089 handle_mm_fault+0x2a7/0x9e0 mm/memory.c:5243 do_user_addr_fault+0x51a/0x1210 arch/x86/mm/fault.c:1440 handle_page_fault arch/x86/mm/fault.c:1534 [inline] exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:__put_user_4+0x11/0x20 arch/x86/lib/putuser.S:91 Code: fa 0f 01 cb 66 89 01 31 c9 0f 01 ca c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <89> 01 31 c9 0f 01 ca c3 0f 1f 80 00 00 00 00 f3 0f 1e fa f3 0f 1e RSP: 0018:ffffc90004217ec0 EFLAGS: 00050206 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000020000000 RDX: 1ffff1100e18dd2b RSI: ffffffff82245cf8 RDI: ffff888070c6e958 RBP: ffffc90004217ef8 R08: 0000000000000001 R09: ffffffff8e7a9657 R10: fffffbfff1cf52ca R11: 0000000000000001 R12: ffff888070c6e4f0 R13: 0000000020000000 R14: ffff888070c6e518 R15: ffff88807bc6ec80 reiserfs_ioctl+0x20d/0x330 fs/reiserfs/ioctl.c:96 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x19d/0x210 fs/ioctl.c:856 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 RIP: 0033:0x7f934c6b1649 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 18 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe3f7edce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000cee5 RCX: 00007f934c6b1649 RDX: 0000000020000000 RSI: 0000000080087601 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3f7edd1c R13: 00007ffe3f7edd50 R14: 00007ffe3f7edd30 R15: 000000000000002a ---------------- Code disassembly (best guess): 0: fa cli 1: 0f 01 cb stac 4: 66 89 01 mov %ax,(%rcx) 7: 31 c9 xor %ecx,%ecx 9: 0f 01 ca clac c: c3 retq d: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 14: 00 00 00 00 18: 90 nop 19: f3 0f 1e fa endbr64 1d: 48 89 cb mov %rcx,%rbx 20: 48 c1 fb 3f sar $0x3f,%rbx 24: 48 09 d9 or %rbx,%rcx 27: 0f 01 cb stac * 2a: 89 01 mov %eax,(%rcx) <-- trapping instruction 2c: 31 c9 xor %ecx,%ecx 2e: 0f 01 ca clac 31: c3 retq 32: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 39: f3 0f 1e fa endbr64 3d: f3 repz 3e: 0f .byte 0xf 3f: 1e (bad) --- 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.