From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f77.google.com (mail-oo1-f77.google.com [209.85.161.77]) (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 095C530B514 for ; Fri, 6 Feb 2026 07:24:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770362665; cv=none; b=C15wRk0d3nvfv8uU81cu4Vd9xrkw9gSShW8ZgUSXMSpW7wTi0uGhC/aVF+o7ecjFHEAB+5yNCjcdlBf4nwEQXVh78VSoHlSuImA45h1vf3qcrfqDmENF0m6Jynw3g6llh5Qn8sSxrUBHe/k89N5g1GuLlHdSVNI27aA87aCuyZg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770362665; c=relaxed/simple; bh=iBARMvGi2nN6CAOktKdGzKVjcEbruvi7SYevqC6gKRg=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=CTEQH4pnYib4DNwFD47nPe7Hn180zIMAJ0bN0PWYT7McJcH4LPBxE7h157gAcYA1DRTu5kFRDt8+m0FT2jjtUBcS6qWhoQgBczMSpye3eLgygYkbZ8p6EZ5yRQD/QqtRGnuTHq4erO9n53dkvE3Kak+aHjA/SZ4442QGZWYyw6g= 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=209.85.161.77 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-oo1-f77.google.com with SMTP id 006d021491bc7-663126bb42dso7853029eaf.1 for ; Thu, 05 Feb 2026 23:24:24 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770362664; x=1770967464; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=ot6ual0l9jo2XolXnfpiqkyLpmBuznoc4sQK0e9mC6I=; b=b7Sd1NxuTKABeolrOsJCt5uSj760na/JtGMCNFFjOyKYEycBLKvK+ZQzdGxFuBNe2u 2MN9ef1WD+ni66Cw/4VWpHyn4Z4S94Sh+DXKosxwzy6EK53Do0AHFRZBFQ5X/7EOv3Bb aKPdn0U6uq24tpdcpPb9LN4zu+wo2tDdGLeGwD0woDTXSlydQO8n/sc83e7qJTO1cFdn grjToyZ7zTJvMMbTuPb0lO1pKCumlQqXlMncMC0lWIDfNPT7O+NbhNl1XLLqESf+yk67 UVjBvvtsvMoYUtCmvE7Gc56kVGGIrhoKN8d+NY+fA/mHCX6ThfA6hrYvkVHS0QztCq6Y fZFA== X-Forwarded-Encrypted: i=1; AJvYcCX5381gez4DSZBgrGkTycyOJynnYYaKaqbgTV0lnm/xYMvWGOCowkaNyMhce/FXHo0B8RLc0VE/6RgULzo=@vger.kernel.org X-Gm-Message-State: AOJu0YygbWlY/BPFF8StqOv1Z8x2fcBKlOuYCneIm5U8wf6irOPXdObA 7XukfJfDMtU4ildwITZbj+vYxC9mifJ5nXgu9DcWP+yeWHTZoSkWxQ9DOTIHWJm2RaNGPW2+k2i Pb487BYIP1Ej+IhOgy222JkKRDtLj0zGvyl0q8+3kv0R9v6FceNSuDtQN3Yo= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2202:b0:663:d06:81e2 with SMTP id 006d021491bc7-66d09cabe40mr920061eaf.1.1770362664044; Thu, 05 Feb 2026 23:24:24 -0800 (PST) Date: Thu, 05 Feb 2026 23:24:24 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69859728.050a0220.3b3015.0033.GAE@google.com> Subject: [syzbot] [cgroups?] [mm?] KASAN: wild-memory-access Read in lookup_swap_cgroup_id (2) From: syzbot To: akpm@linux-foundation.org, cgroups@vger.kernel.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@kernel.org, muchun.song@linux.dev, roman.gushchin@linux.dev, shakeel.butt@linux.dev, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 18f7fcd5e69a Linux 6.19-rc8 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1428fc5a580000 kernel config: https://syzkaller.appspot.com/x/.config?x=f1fac0919970b671 dashboard link: https://syzkaller.appspot.com/bug?extid=e12bd9ca48157add237a compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2c19d9acc149/disk-18f7fcd5.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/02cf07c94e58/vmlinux-18f7fcd5.xz kernel image: https://storage.googleapis.com/syzbot-assets/84011cec9819/bzImage-18f7fcd5.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e12bd9ca48157add237a@syzkaller.appspotmail.com ================================================================== BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: wild-memory-access in __swap_cgroup_id_lookup mm/swap_cgroup.c:28 [inline] BUG: KASAN: wild-memory-access in lookup_swap_cgroup_id+0xf9/0x1a0 mm/swap_cgroup.c:127 Read of size 4 at addr 0007fffffffffffc by task syz.5.3598/20029 CPU: 1 UID: 0 PID: 20029 Comm: syz.5.3598 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 kasan_report+0xdf/0x1a0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] __swap_cgroup_id_lookup mm/swap_cgroup.c:28 [inline] lookup_swap_cgroup_id+0xf9/0x1a0 mm/swap_cgroup.c:127 swap_pte_batch+0x3c3/0x720 mm/internal.h:390 zap_nonpresent_ptes mm/memory.c:1749 [inline] do_zap_pte_range mm/memory.c:1818 [inline] zap_pte_range mm/memory.c:1858 [inline] zap_pmd_range mm/memory.c:1950 [inline] zap_pud_range mm/memory.c:1978 [inline] zap_p4d_range mm/memory.c:1999 [inline] unmap_page_range+0x1f6f/0x43e0 mm/memory.c:2020 unmap_single_vma+0x153/0x240 mm/memory.c:2062 unmap_vmas+0x218/0x470 mm/memory.c:2104 exit_mmap+0x181/0xae0 mm/mmap.c:1277 __mmput+0x12a/0x410 kernel/fork.c:1173 mmput+0x67/0x80 kernel/fork.c:1196 exit_mm kernel/exit.c:581 [inline] do_exit+0x78a/0x2a30 kernel/exit.c:959 do_group_exit+0xd5/0x2a0 kernel/exit.c:1112 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x86/0x4b0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4fe/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2f8f19aeb9 Code: Unable to access opcode bytes at 0x7f2f8f19ae8f. RSP: 002b:00007f2f900350e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f2f8f416098 RCX: 00007f2f8f19aeb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2f8f416098 RBP: 00007f2f8f416090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2f8f416128 R14: 00007ffc0c8cc050 R15: 00007ffc0c8cc138 ================================================================== --- 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. 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