From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f205.google.com (mail-il1-f205.google.com [209.85.166.205]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 88DAF253B52 for ; Sat, 2 Aug 2025 19:20:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.205 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754162435; cv=none; b=sjasNPNCdlZQlF4ZpOb3wq+qzpq2l/rJvZ0DVfdaQvyzE9pZaYEOF+zEvQilwBgOGwpAk1TI9eEysC3F31XdfySubBuBubZdMkgH4N8VCn5gvdh3F9GN/VGARbOPkngxnTSs2tAieSB637quLp8ddMTTNMYuBJ2FDrOm5PCvxp4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754162435; c=relaxed/simple; bh=OzYN3c/vR9xEeZMF8IB9ORyTabrQuYk8fNI43pt+iTM=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=sNWAwzMMg0/B58HCuum0M2qbNtIalyjz0bQd2jaYMkq7tV55kwPHcy/mmF8FLeUfveB6Tp4MRIEl7ppPMVGk8Ml2JkVzIRApDzmgFmaO8FzIBnlJZGQTIL6FxahJ8OFcqVvruecJDvz7yi5iZhOaT3kNJg2S9zZXj732SQTkqUo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.205 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f205.google.com with SMTP id e9e14a558f8ab-3e410d87897so17719335ab.0 for ; Sat, 02 Aug 2025 12:20:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754162433; x=1754767233; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=SBtAwyu1aSvzaygWr/xhjUHPu9QFCoUi6C4sbqeWEnI=; b=KWk27yvz/fTz9ONtnnlkQRptCKgJnAkurrg1mouqyQEvOKK6KMvWl521LHAEo5ZMa3 fpdS3MM9gw+x1Q+kRZyTnCsr0n5/EeMvDJumTX2eBXw0Bg/UBWBBagczJBqp1CGKbZ8w ybaBlEi0gWgPQ0v/4zbo3qBnJCqlEG1PN1MEbE3jpBUaN4Hlpn4gK93SiwlkkvWIGFvH TAPdO/OSSH7TKf09fexCDddZQzoKSzKnnK0B+bKNsEoXPz1cERRrv4u6fDTON01o29yv 6sOJyibl0vdn6WKGuQFb62LlPHVgTe11+1qe9ujI6X7A0W/r+YZkYKc4VOdwrcEFPPkx b38w== X-Forwarded-Encrypted: i=1; AJvYcCX7rIYxp25iRfNhhFPSeOstDNcsWeIZKhxsGceDPMUP6ifwxP4r7sGa1Ow1/Or1pdyjRvQNbCal0KlneA==@vger.kernel.org X-Gm-Message-State: AOJu0YyfL84MlDN+5bqnueKCGNmnMvrxTLl5c+ag7AL5VMCJrS+BLMwR DMqOenUYiD7TtolzJKvx4j849cSGvR8JA53vEkaLJNkWFsZ+sjCtCpgLMNT80447PkvYraYvhJZ 9pIyQPaGt5paQUOd2cp5cKHBr8FXBLE4AEZXPQDmadsDuopGAMmFa1S57eN0= X-Google-Smtp-Source: AGHT+IFBlc22xGVxkUsO0Mw0GWNmdmLQ7vqgQnl0o6Sh9XS15RkxsdRAhXlaA0P9N5b4nghIlXrofGX1Zh7YFZCrvbh3bj6I6JNx Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:398e:b0:3e3:d499:73f with SMTP id e9e14a558f8ab-3e4161b735cmr92781645ab.18.1754162432751; Sat, 02 Aug 2025 12:20:32 -0700 (PDT) Date: Sat, 02 Aug 2025 12:20:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <688e6500.050a0220.f0410.0141.GAE@google.com> Subject: [syzbot] [block?] general protection fault in zcomp_available_show From: syzbot To: axboe@kernel.dk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, minchan@kernel.org, senozhatsky@chromium.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: a6923c06a3b2 Merge tag 'bpf-fixes' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=155ddcf0580000 kernel config: https://syzkaller.appspot.com/x/.config?x=6f81cd75c44834c1 dashboard link: https://syzkaller.appspot.com/bug?extid=1a281a451fd8c0945d07 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2a74fc5b80ca/disk-a6923c06.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9a2267e0785c/vmlinux-a6923c06.xz kernel image: https://storage.googleapis.com/syzbot-assets/4dbddcb2f621/bzImage-a6923c06.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1a281a451fd8c0945d07@syzkaller.appspotmail.com Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 16120 Comm: syz.5.1782 Tainted: G U 6.16.0-syzkaller-11105-ga6923c06a3b2 #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:strcmp+0x39/0xb0 lib/string.c:283 Code: df 41 54 55 53 48 89 fb 48 83 ec 08 eb 08 40 84 ed 74 61 4c 89 e6 48 89 df 48 83 c3 01 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 04 84 c0 75 58 48 89 f0 48 89 f2 0f b6 6b RSP: 0018:ffffc9000d96f7c0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffc9001895a000 RDX: 0000000000000000 RSI: ffffffff8c440580 RDI: 0000000000000000 RBP: ffffffff8c43f520 R08: 0000000000000001 R09: ffffed1004bdca09 R10: ffff888025ee504f R11: 0000000000000000 R12: ffff88807c3f6000 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007f26269916c0(0000) GS:ffff8881247d6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30cffff8 CR3: 000000002a034000 CR4: 00000000003526f0 Call Trace: zcomp_available_show+0x73/0x130 drivers/block/zram/zcomp.c:98 __comp_algorithm_show drivers/block/zram/zram_drv.c:1234 [inline] comp_algorithm_show+0x98/0xd0 drivers/block/zram/zram_drv.c:1391 dev_attr_show+0x53/0xe0 drivers/base/core.c:2421 sysfs_kf_seq_show+0x213/0x3e0 fs/sysfs/file.c:65 seq_read_iter+0x509/0x12c0 fs/seq_file.c:230 kernfs_fop_read_iter+0x40f/0x5a0 fs/kernfs/file.c:279 copy_splice_read+0x615/0xba0 fs/splice.c:363 do_splice_read fs/splice.c:979 [inline] do_splice_read+0x285/0x370 fs/splice.c:953 splice_direct_to_actor+0x2a1/0xa30 fs/splice.c:1083 do_splice_direct_actor fs/splice.c:1201 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1227 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2628f8eb69 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2626991038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f26291b6240 RCX: 00007f2628f8eb69 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 00007f2629011df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f26291b6240 R15: 00007ffff2fc35d8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:strcmp+0x39/0xb0 lib/string.c:283 Code: df 41 54 55 53 48 89 fb 48 83 ec 08 eb 08 40 84 ed 74 61 4c 89 e6 48 89 df 48 83 c3 01 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 04 84 c0 75 58 48 89 f0 48 89 f2 0f b6 6b RSP: 0018:ffffc9000d96f7c0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffc9001895a000 RDX: 0000000000000000 RSI: ffffffff8c440580 RDI: 0000000000000000 RBP: ffffffff8c43f520 R08: 0000000000000001 R09: ffffed1004bdca09 R10: ffff888025ee504f R11: 0000000000000000 R12: ffff88807c3f6000 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007f26269916c0(0000) GS:ffff8881247d6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000c5d000 CR3: 000000002a034000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: df 41 54 filds 0x54(%rcx) 3: 55 push %rbp 4: 53 push %rbx 5: 48 89 fb mov %rdi,%rbx 8: 48 83 ec 08 sub $0x8,%rsp c: eb 08 jmp 0x16 e: 40 84 ed test %bpl,%bpl 11: 74 61 je 0x74 13: 4c 89 e6 mov %r12,%rsi 16: 48 89 df mov %rbx,%rdi 19: 48 83 c3 01 add $0x1,%rbx 1d: 48 89 f8 mov %rdi,%rax 20: 48 89 fa mov %rdi,%rdx 23: 48 c1 e8 03 shr $0x3,%rax 27: 83 e2 07 and $0x7,%edx * 2a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax <-- trapping instruction 2f: 38 d0 cmp %dl,%al 31: 7f 04 jg 0x37 33: 84 c0 test %al,%al 35: 75 58 jne 0x8f 37: 48 89 f0 mov %rsi,%rax 3a: 48 89 f2 mov %rsi,%rdx 3d: 0f .byte 0xf 3e: b6 6b mov $0x6b,%dh --- 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 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