From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1854513A41E; Tue, 18 Jun 2024 13:13:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718716397; cv=none; b=W4bji7H4Yyo+AGGbT5v4WZeiDgJfDWMLi5rmtl4apg0YYReWMHIk0IE+Yw3FjI5slNCTfNWVa46iqaTYD3s3zyTSwEU3J3FFsoNa6XxxomrXQNdRKbTD4rblNudgiRKbYmiqxi3KBwNAt6SsVLBpba2s5RPUVShHQSo9RHXqpzw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718716397; c=relaxed/simple; bh=FNFgHcepOTXql9G+zXM+zHFHWhMbN3s6lrBubeAhPG8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HJv17gs54WyrQmtTjPisXI7sw3B7Z6dvGXQ1s2RENRxXb/WovSh5GbcJkEaESqWX0TjzWqrtvqiv0xPaZhvpKcYCEkDrC4omjk2hapz2oYC+84l6A565GoFDrJ7/XsRUxaoE/hdBRM/ZIeaqW1wuRYbzjBfPA+oAVkLnGAnsctM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Y4ny0p3s; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Y4ny0p3s" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56F6AC3277B; Tue, 18 Jun 2024 13:13:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1718716396; bh=FNFgHcepOTXql9G+zXM+zHFHWhMbN3s6lrBubeAhPG8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y4ny0p3sNCuPyWadQ6fTssVdhv1WGasHB30dCl7bb/dOj1QjaKyFuRxLeSu/sfu+o NEDylWcBBURUVPtrlWvlrdzYJpfqHhueDIm7EbKymcPar76qdlOr14XfmYyZqoY/an s/Kbrv+GrJAYJudvKyWwA0UKeCP1STTM9Kw/WFj0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chuck Lever , Jeff Layton , Sasha Levin Subject: [PATCH 5.10 633/770] NFSD: Protect against send buffer overflow in NFSv2 READDIR Date: Tue, 18 Jun 2024 14:38:06 +0200 Message-ID: <20240618123431.718549671@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240618123407.280171066@linuxfoundation.org> References: <20240618123407.280171066@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever [ Upstream commit 00b4492686e0497fdb924a9d4c8f6f99377e176c ] Restore the previous limit on the @count argument to prevent a buffer overflow attack. Fixes: 53b1119a6e50 ("NFSD: Fix READDIR buffer overflow") Signed-off-by: Chuck Lever Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- fs/nfsd/nfsproc.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c index e533550a26db5..559603a0a5358 100644 --- a/fs/nfsd/nfsproc.c +++ b/fs/nfsd/nfsproc.c @@ -567,12 +567,11 @@ static void nfsd_init_dirlist_pages(struct svc_rqst *rqstp, struct xdr_buf *buf = &resp->dirlist; struct xdr_stream *xdr = &resp->xdr; - count = clamp(count, (u32)(XDR_UNIT * 2), svc_max_payload(rqstp)); - memset(buf, 0, sizeof(*buf)); /* Reserve room for the NULL ptr & eof flag (-2 words) */ - buf->buflen = count - XDR_UNIT * 2; + buf->buflen = clamp(count, (u32)(XDR_UNIT * 2), (u32)PAGE_SIZE); + buf->buflen -= XDR_UNIT * 2; buf->pages = rqstp->rq_next_page; rqstp->rq_next_page++; -- 2.43.0