From nobody Sat Feb 7 19:08:21 2026 Received: from mail-oi1-f198.google.com (mail-oi1-f198.google.com [209.85.167.198]) (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 84F6D22A4E8 for ; Fri, 9 Jan 2026 08:06:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.198 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767946019; cv=none; b=VnCisd9uIdjxF5FM8oGIrRYoYEfv92/VGxNfVOGLLH94WHD1fKe136FJv//5Cq5NCPpdKjslKHUUekzMIEcMCZfhuUy+96NrG6cZCGXpDQayB57luDc6+jZItYVQXarnSP5tmKwkGv+JXVd3l/AUdrqyrdfKPjfFcKapjoWRbfY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767946019; c=relaxed/simple; bh=U1bp1MYYbpbkXGChTQy19qgWXlEaDBMwPEa7nLJb4WA=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=OwWAjxNons3fMqssOIcCSYcVMXDu6Fp/Y2LwtrdGDdgn34ZEhAGhLx5bxEU9FfHYrf/KK18PLVE95DtJmVk5+QYXe0ddkSDg+NDjFH1UHQBV7nkNX281h3QrU1Yc6IPHMywA9GkDw11SYGG1kG6cVB78oEJbcVXHn+n7ZZzE8YA= 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=209.85.167.198 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-oi1-f198.google.com with SMTP id 5614622812f47-450b5afd932so4078091b6e.2 for ; Fri, 09 Jan 2026 00:06:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767946016; x=1768550816; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=cWNPwEouFG9yzbKe+tvJDgEfP3OppyIQS6Eumuo9fl8=; b=PYLmq+53wQEEYu96zB8PFGZKN9CTYoYsKULqD9Sr3TGqlohqiceZoGpahq7DKQYXo1 BT4vFpsWwio2HytOJDE9jTVqmRVj/Mp2uRe4/dyUPGPbElMTdEqsN3+W/Rb5eoFA4pA6 7gTj7op2ibiLq3MUJpR4L4eOq3ZE7pQ2yUP1iy0RR299yBnPdqH6GuKhdkmKG37Upakp K7fXbM4cw3yMzYG8DNvD/BkiNls6WCzFIljAgq5gOGE0ZWOADy9RrTUSwzAnQLljxvFQ H02xJzbmBKlAlafHuEWDKSobhDrYEaDO3ttuGvF5GyV1vxnmsqLd9pMxZpjlhqJJVUG2 TpEw== X-Gm-Message-State: AOJu0Yz21sGmgE1cgTzG1OgZEGXqrs+4zKz8Z/QqYSTE0Z7v3KKGkf71 sSRUYgh1sWYwNw6BEiGzoFpWzYpyt7i0Z0QUcIkjWZ1c8RIpJJBJ6aH7o4ylcOE3UjRyHQacbbN NnvqMNRoijZmqJd3NPsuLXhKdO05AFTT7b0BQmqbfsq9B/uFMS2xlAxPLX40= X-Google-Smtp-Source: AGHT+IH3I9tPHFchOQLphJ1S8vdL18l3kPLX1snhYkpyqGc8Csn6FoscKDbb6tjZx1A5A5lR8FO0yFFGvjL46+zlWFPXF4E2+vtU Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:c319:b0:45a:6d59:44f5 with SMTP id 5614622812f47-45a6d5950eamr3866628b6e.30.1767946016226; Fri, 09 Jan 2026 00:06:56 -0800 (PST) Date: Fri, 09 Jan 2026 00:06:56 -0800 In-Reply-To: <695faa63.050a0220.1c677c.039b.GAE@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6960b720.050a0220.1c677c.03b9.GAE@google.com> Subject: Forwarded: [PATCH] btrfs: debug folio_alloc_buffers parameters From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com. *** Subject: [PATCH] btrfs: debug folio_alloc_buffers parameters Author: kartikey406@gmail.com #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git= master Debug patch to understand NULL pointer dereference in create_empty_buffers. Print folio_size and blocksize to identify why folio_alloc_buffers returns = NULL. NOT FOR MERGE - debug only. Signed-off-by: Deepanshu Kartikey --- fs/buffer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/buffer.c b/fs/buffer.c index 838c0c571022..487a32faaa16 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -928,7 +928,7 @@ struct buffer_head *folio_alloc_buffers(struct folio *f= olio, unsigned long size, /* The folio lock pins the memcg */ memcg =3D folio_memcg(folio); old_memcg =3D set_active_memcg(memcg); - + pr_err("DEBUG: folio_size=3D%lu blocksize=3D%lu\n",folio_size(folio), siz= e); head =3D NULL; offset =3D folio_size(folio); while ((offset -=3D size) >=3D 0) { --=20 2.43.0