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 BE1D0C433FE for ; Sun, 30 Oct 2022 02:04:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229565AbiJ3CEq (ORCPT ); Sat, 29 Oct 2022 22:04:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59448 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229542AbiJ3CEn (ORCPT ); Sat, 29 Oct 2022 22:04:43 -0400 Received: from mail-io1-f72.google.com (mail-io1-f72.google.com [209.85.166.72]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20334F010 for ; Sat, 29 Oct 2022 19:04:41 -0700 (PDT) Received: by mail-io1-f72.google.com with SMTP id a6-20020a056602208600b006bff2e56943so6408030ioa.11 for ; Sat, 29 Oct 2022 19:04:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=0KENEzeOv1xiMZcfoPEnQtIZHWEKHhSdkzIqMFu+aGI=; b=i8RB47pncf4wNh9EFTqVrFX2Wr7irUce0+/V2NxD/RVLW256Ni/BXNmAGRxLyxhDjj C+fe5JIJdzacM/fF+l2LpvY5IOU1UGgqLdOrS5AMSMZeSuq2B4tiSE0/mBi3/JBmfvea 57qG5kCE0dsRoeySmJeGh5pbog48qzQwuvKPcwDTtc6apValLepEnIM2cWc86pZVs49f TqPVM/GteldJKACO3+0cb6yCBYn+wPplbBt5cTFFeeWlPMpyIzJsjjFrhBZ01Sm9espP ec6GrIaI14bEZNY9nXRr4fIFKH39d5YMV92I3g0TlY++v69pc/9JGQI7IUFNItYfRE8W DX1A== X-Gm-Message-State: ACrzQf0ZyfRJm80LE9B6xX7xksKf14otvmlhVRwPENYbcBrB6cYTK5Zq NKBFriTMam/OqHnW2dlgnBayyyZGIzHNUvtQyDQuGkyewr1N X-Google-Smtp-Source: AMsMyM48K6HHRrjV1hPIRWtTaEX59WKj5KCv0ljwUTba5ZPWf7CK7UiLkaxMzGY8ya0tN9weoD0hkZvkncXTp1DqfqFG/Y+srqVX MIME-Version: 1.0 X-Received: by 2002:a02:cc58:0:b0:375:4e26:f408 with SMTP id i24-20020a02cc58000000b003754e26f408mr508688jaq.230.1667095480429; Sat, 29 Oct 2022 19:04:40 -0700 (PDT) Date: Sat, 29 Oct 2022 19:04:40 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000eaf19105ec36e9b8@google.com> Subject: [syzbot] KASAN: null-ptr-deref Read in drop_buffers From: syzbot To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tj@kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 55be6084c8e0 Merge tag 'timers-core-2022-10-05' of git://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1465473a880000 kernel config: https://syzkaller.appspot.com/x/.config?x=c29b6436e994d72e dashboard link: https://syzkaller.appspot.com/bug?extid=fbdb4ec578ebdcfb9ed2 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, 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/c8f5131ab57d/disk-55be6084.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/77167f226f35/vmlinux-55be6084.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+fbdb4ec578ebdcfb9ed2@syzkaller.appspotmail.com ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: null-ptr-deref in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: null-ptr-deref in buffer_busy fs/buffer.c:2856 [inline] BUG: KASAN: null-ptr-deref in drop_buffers+0x61/0x2f0 fs/buffer.c:2868 Read of size 4 at addr 0000000000000060 by task syz-executor.5/24786 CPU: 0 PID: 24786 Comm: syz-executor.5 Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_report+0xf1/0x220 mm/kasan/report.c:436 kasan_report+0xfb/0x130 mm/kasan/report.c:495 kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] buffer_busy fs/buffer.c:2856 [inline] drop_buffers+0x61/0x2f0 fs/buffer.c:2868 try_to_free_buffers+0x2b1/0x640 fs/buffer.c:2898 shrink_page_list+0x3be3/0x6260 mm/vmscan.c:1939 shrink_inactive_list+0x5cd/0xc10 mm/vmscan.c:2447 shrink_list mm/vmscan.c:2674 [inline] shrink_lruvec+0x489/0xc80 mm/vmscan.c:2991 shrink_node_memcgs+0x360/0x770 mm/vmscan.c:3180 shrink_node+0xe9f/0x2040 mm/vmscan.c:3304 shrink_zones+0x4fb/0xc40 mm/vmscan.c:3542 do_try_to_free_pages+0x215/0xcd0 mm/vmscan.c:3601 try_to_free_mem_cgroup_pages+0x3cb/0x6d0 mm/vmscan.c:3916 memory_high_write+0x24f/0x3c0 mm/memcontrol.c:6303 cgroup_file_write+0x2ab/0x780 kernel/cgroup/cgroup.c:3962 kernfs_fop_write_iter+0x3ac/0x500 fs/kernfs/file.c:330 do_iter_write+0x6f0/0xc50 fs/read_write.c:861 iter_file_splice_write+0x830/0xff0 fs/splice.c:686 do_splice_from fs/splice.c:764 [inline] direct_splice_actor+0xe6/0x1c0 fs/splice.c:931 splice_direct_to_actor+0x4e4/0xc00 fs/splice.c:886 do_splice_direct+0x2a0/0x3f0 fs/splice.c:974 do_sendfile+0x641/0xfd0 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1323 [inline] __se_sys_sendfile64+0x178/0x1e0 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2ac848b5a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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:00007f2ac9545168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f2ac85abf80 RCX: 00007f2ac848b5a9 RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000007 RBP: 00007f2ac84e6580 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc10d5a64f R14: 00007f2ac9545300 R15: 0000000000022000 ================================================================== --- This report is generated by a bot. 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