Re: [PATCH] isdn/i4l: fetch the ppp_write buffer in one shot

From: Meng Xu Date: Tue, 19 Sep 2017 21:49:55 -0400 > In isdn_ppp_write(), the header (i.e., protobuf) of the buffer is > fetched twice from userspace. The first fetch is used to peek at the > protocol of the message and reset the huptimer if necessary; while the > second fetch copies in the whol

[PATCH] isdn/i4l: fetch the ppp_write buffer in one shot

In isdn_ppp_write(), the header (i.e., protobuf) of the buffer is fetched twice from userspace. The first fetch is used to peek at the protocol of the message and reset the huptimer if necessary; while the second fetch copies in the whole buffer. However, given that buf resides in userspace memory,