Use the FTRACE_OPS_FL_IPMODIFY flag to prevent conflicts with other
ftrace users who also modify regs->ip.
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NPetr Mladek <pmladek@suse.cz>
Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The execution flow redirection related implemention in the livepatch
ftrace handler is depended on the specific architecture. This patch
introduces klp_arch_set_pc(like kgdb_arch_set_pc) interface to change
the pt_regs.
Signed-off-by: NLi Bin <huawei.libin@huawei.com>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This commit introduces code for the live patching core.  It implements
an ftrace-based mechanism and kernel interface for doing live patching
of kernel and kernel module functions.

It represents the greatest common functionality set between kpatch and
kgraft and can accept patches built using either method.

This first version does not implement any consistency mechanism that
ensures that old and new code do not run together.  In practice, ~90% of
CVEs are safe to apply in this way, since they simply add a conditional
check.  However, any function change that can not execute safely with
the old version of the function can _not_ be safely applied in this
version.

[ jkosina@suse.cz: due to the number of contributions that got folded into
  this original patch from Seth Jennings, add SUSE's copyright as well, as
  discussed via e-mail ]
Signed-off-by: NSeth Jennings <sjenning@redhat.com>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: NMiroslav Benes <mbenes@suse.cz>
Reviewed-by: NPetr Mladek <pmladek@suse.cz>
Reviewed-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: NMiroslav Benes <mbenes@suse.cz>
Signed-off-by: NPetr Mladek <pmladek@suse.cz>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>