914a274320
commit ec6e4d863258d4bfb36d48d5e3ef68140234d688 upstream.
Wait to mark the TSS as busy during LTR emulation until after all fault
checks for the LTR have passed. Specifically, don't mark the TSS busy if
the new TSS base is non-canonical.
Opportunistically drop the one-off !seg_desc.PRESENT check for TR as the
only reason for the early check was to avoid marking a !PRESENT TSS as
busy, i.e. the common !PRESENT is now done before setting the busy bit.
Fixes: e37a75a13cda ("KVM: x86: Emulator ignores LDTR/TR extended base on LLDT/LTR")
Reported-by: syzbot+760a73552f47a8cd0fd9@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Hou Wenlong <houwenlong.hwl@antgroup.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220711232750.1092012-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.