From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E947D388882 for ; Tue, 12 May 2026 12:35:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778589310; cv=none; b=JUFnx+RavLA8tBUIuQhbF89H+guey+JTiCJhfQHXMBrZP8s914n4PLJF0lCaKgnjKrEZnEUR5r+T+gfk5RrsqmBOeEOmG8c5VljXEtipSLjrj9Y5JJe2ZDF278EiUsRcCwtVqSy4N1da4b+ILR/dThjCgxeRA4c3CSLTKI9czyQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778589310; c=relaxed/simple; bh=sxih3BTDZzJ2bsUF2D6f64sfz9xkArtTKlvgnT0LUh0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IKc7jdoG1D4HpTnKZIGeT6LU5m1icjMfLmMCY+GbNkXMwuiSS8ORnR3VJ0ToAERQIn5BM8/BsqyAJtEDD45tS4WSfXwPhTMD5RIL96ZhsUfB2WFVZ95LuVAHeiOkjtfi8LDQdAkdNMpf1X04CzsoJjTX4d9xnM2/zZl6H2iAuWY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=aUMN8/H9; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="aUMN8/H9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1778589295; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MAmZUPUCJuuZNr89UZiegqkhZYwnj4y64aSMrWWXqcs=; b=aUMN8/H9y8edC5nz+RaZhAttdvuinx/dVI/anoIen5qHu5ysX6NpQwnmlNrAef8lIvyUrf eFpMurqiS6/I1OrupAQYrh4PjNczSDYakuK3t7AWVnUq4Y+GqLQ7WyAmUppOdI90zP0a5v 1ID8ELsEgXTcKdXSWv9LlMMOmjL/UQE= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-208-piGjhrQqNFu2y0lHo3mczQ-1; Tue, 12 May 2026 08:34:51 -0400 X-MC-Unique: piGjhrQqNFu2y0lHo3mczQ-1 X-Mimecast-MFC-AGG-ID: piGjhrQqNFu2y0lHo3mczQ_1778589290 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 08ACC19560A1; Tue, 12 May 2026 12:34:50 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.44.48.83]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 7509319560A6; Tue, 12 May 2026 12:34:46 +0000 (UTC) From: David Howells To: Christian Brauner Cc: David Howells , Paulo Alcantara , netfs@lists.linux.dev, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Matthew Wilcox Subject: [PATCH v6 08/24] netfs: Fix potential uninitialised var in netfs_extract_user_iter() Date: Tue, 12 May 2026 13:33:45 +0100 Message-ID: <20260512123404.719402-9-dhowells@redhat.com> In-Reply-To: <20260512123404.719402-1-dhowells@redhat.com> References: <20260512123404.719402-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 In netfs_extract_user_iter(), if it's given a zero-length iterator, it will fall through the loop without setting ret, and so the error handling behaviour will be undefined, depending on whether ret happens to be negative. The value of ret then propagates back up the callstack. Fix this by presetting ret to 0. Fixes: 85dd2c8ff368 ("netfs: Add a function to extract a UBUF or IOVEC into a BVEC iterator") Closes: https://sashiko.dev/#/patchset/20260414082004.3756080-1-dhowells%40redhat.com Signed-off-by: David Howells cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org --- fs/netfs/iterator.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/netfs/iterator.c b/fs/netfs/iterator.c index 154a14bb2d7f..6903028b7162 100644 --- a/fs/netfs/iterator.c +++ b/fs/netfs/iterator.c @@ -43,7 +43,7 @@ ssize_t netfs_extract_user_iter(struct iov_iter *orig, size_t orig_len, unsigned int max_pages; unsigned int npages = 0; unsigned int i; - ssize_t ret; + ssize_t ret = 0; size_t count = orig_len, offset, len; size_t bv_size, pg_size;