From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 3321647278B for ; Tue, 28 Apr 2026 13:19:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777382359; cv=none; b=JbnBZeK9KW7TvYEfLSbcorvAufRsyUOhuKW/KdeUriYa6TmAbr3mwbMKeTTB68UhFSJ87DswP9lPuNxd+Q11B9KEydKot/BwPttsH3fn7w6BTYwNadKNS9RkbvWPhg6HOlSojkzEIBd07WnluZNcFNVlCOUSkVHzVxhAEI/8aTg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777382359; c=relaxed/simple; bh=fxR0HRvSv22xXvXZ87M+p66ej2r+Sv2DAKvy6zA3uPg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:content-type; b=uUN2l41Bv3tMNBiIU26JXP4nFCNR1eLHrLPVTJI5/s7w3vng/NMg8if/cogZGlqMzOM46NjtJpr9zbfpYap4wzAxM1SgsGNMhYEDgafWJmmv2AqjprIHMDo5gb+07pnQKbvV3w0h8HG90tscPLAF1gHE/OQXu0exfBRP0J39LM0= 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=PyBmJIj+; arc=none smtp.client-ip=170.10.129.124 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="PyBmJIj+" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1777382357; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VAlXvNFC3a/D86PNh8eSdyFG14ll2LJIPxlUeY75MuY=; b=PyBmJIj+k5qQDSh3aoVwQ5Kf28TujAKzpFFEAC8UcXgLV+Ccfn2y8sro2iGotc36Xlq0et dTHv+rQqYmMMf94Q8tvR1Uap6RmbO+SX+Snv9ESHmV3MKcNvb1GVfMKKAs1hHlKcNMQiz3 Zgkv0+JKxsF1bWlbDfWfvq4bP9P4RK0= Received: from mx-prod-mc-03.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-661-DFDOW-0ZOJKBfmUktfd99Q-1; Tue, 28 Apr 2026 09:19:13 -0400 X-MC-Unique: DFDOW-0ZOJKBfmUktfd99Q-1 X-Mimecast-MFC-AGG-ID: DFDOW-0ZOJKBfmUktfd99Q_1777382351 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id AF94C18AB432; Tue, 28 Apr 2026 13:18:51 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.44.32.126]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id B34761800446; Tue, 28 Apr 2026 13:18:48 +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 v5 10/24] netfs: Fix potential uninitialised var in netfs_extract_user_iter() Date: Tue, 28 Apr 2026 14:17:40 +0100 Message-ID: <20260428131756.922303-11-dhowells@redhat.com> In-Reply-To: <20260428131756.922303-1-dhowells@redhat.com> References: <20260428131756.922303-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: netfs@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 X-Mimecast-MFC-PROC-ID: I2kNERZWh2UO2wYiEFue--0VPZkbirZfhnoUJhsVyZ8_1777382351 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true 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 932f745fa3b5..8b70d9567739 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;