CVS commit: src/sys/arch/amd64/amd64

["Maxime Villard" <maxv%netbsd.org@localhost>]

Module Name:    src
Committed By:   maxv
Date:           Sun Feb  5 08:19:05 UTC 2017

Modified Files:
        src/sys/arch/amd64/amd64: machdep.c

Log Message:
In cpu_mcontext_validate, treat %cs differently depending on whether a user
LDT is set; just check the permission without checking the location (which
may change).

In valid_user_selector, don't check the length of the LDT. This is racy
because pm_ldt_len could be updated by another thread, and useless since
the length is already referenced in ldtr (ldt_alloc), which means that any
overflow will fault in userland.

Also, don't check the permission of the segment pointed to; this too is
racy, and we don't care either since the permissions are checked earlier
in x86_set_ldt1.

Pass 1/2.


To generate a diff of this commit:
cvs rdiff -u -r1.249 -r1.250 src/sys/arch/amd64/amd64/machdep.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.