From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7AE1844CAD7; Wed, 23 Sep 2026 14:55:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790175359; cv=none; b=eHEMGL25n+i54RVtYuX9HJnazgtAuQDwg7MOiaTjsqUcE53j++/tvQm+2m9LzINYZLEAXhVDtARWvFMXXvl4rPIRylkNjdn8bfrjZHok9oHp/EvUz48UQ0WhSFYfQK+1RBn/7DsUo/XRkorkL6yBG0GCWW56h8GuDmB6XJ+zWpM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790175359; c=relaxed/simple; bh=U0THLm6IxjaO+8LwcLQ0gzrJF4PlbkIeMUryRqNLm74=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hvBdsDbVx0aGuV2uwttx17D5E4xC54vuwOcC2JSyAyUjnsV/wOQOu6xgmdn1RV3kQ4LmgebyRq28nZRLapSI5KVuHyx1lbwg1jrkmADv0RbXGC0vcur8uweSJU4V8N83R0iT91f8kzmVf5tJM4LvWN1UGPhsQAmAnxMJS8scn3w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lvc4/R0s; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lvc4/R0s" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B7131F000FF; Wed, 23 Sep 2026 14:55:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790175358; bh=44gr0ugpP3RStkwNtODTnAUCtMY2dq8+9bz47NcmkkI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=lvc4/R0sYFOWbaXufho26+IHM0YNohyIwl47Y3xNHOopalb83DvTUXy8yK03hygAx LmjbfdDmofRAFM9IL51JG3vamqWVdgDLUFN7GEAgKnobhQx+4NKY6CetUVpRRH1OUI xZA8yyACA1uKppjX2UjhENVAZDMinueNAh2EWjt8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Frank Sorenson , David Howells , Paulo Alcantara , Sasha Levin Subject: [PATCH 6.18 391/398] smb: client: fix reparse buffer bounds in cifs_query_reparse_point() Date: Wed, 23 Sep 2026 16:07:45 +0200 Message-ID: <20260923140653.604804913@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140643.441954610@linuxfoundation.org> References: <20260923140643.441954610@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Frank Sorenson [ Upstream commit 5f0306e731e2f46e91419eae57eee3a241c055e0 ] In cifs_query_reparse_point(), the start >= end check before casting to struct reparse_data_buffer * only ensures the start pointer is within the response. It fails to verify that there is enough space remaining for the fixed 8-byte header of the structure. If a server provides a DataOffset that leaves less than 8 bytes remaining, the check passes, but subsequent reads of ReparseTag and ReparseDataLength will occur out-of-bounds. Fix this by ensuring the remaining space is at least the size of the reparse_data_buffer structure before accessing its fields. Fixes: 56e84c64fc25 ("cifs: Fix validation of SMB1 query reparse point response") Cc: stable@vger.kernel.org Signed-off-by: Frank Sorenson Reviewed-by: David Howells Signed-off-by: Paulo Alcantara [ Adjusted context to retain existing `rc = -EIO` error handling instead of upstream `smb_EIO2()`. ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/smb/client/cifssmb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/smb/client/cifssmb.c +++ b/fs/smb/client/cifssmb.c @@ -3015,7 +3015,7 @@ int cifs_query_reparse_point(const unsig end = 2 + get_bcc(&io_rsp->hdr) + (__u8 *)&io_rsp->ByteCount; start = (__u8 *)&io_rsp->hdr.Protocol + data_offset; - if (start >= end) { + if (start >= end || (size_t)(end - start) < sizeof(*buf)) { rc = -EIO; goto error; }