commit 71c95825289f585014fe9741b051d32a7a916680 upstream.
The unwind_state 'error' field is used to inform the reliable unwinding
code that the stack trace can't be trusted. Set this field for all
errors in __unwind_start().
Also, move the zeroing out of the unwind_state struct to before the ORC
table initialization check, to prevent the caller from reading
uninitialized data if the ORC table is corrupted.
Fixes: af085d9084 ("stacktrace/x86: add function for detecting reliable stack traces")
Fixes: d3a0910401 ("x86/unwinder/orc: Dont bail on stack overflow")
Fixes: 98d0c8ebf77e ("x86/unwind/orc: Prevent unwinding before ORC initialization")
Reported-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/d6ac7215a84ca92b895fdd2e1aa546729417e6e6.1589487277.git.jpoimboe@redhat.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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.
7f95c11060