4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Oleg Nesterov <o...@redhat.com> commit 90718e32e1dcc2479acfa208ccfc6442850b594c upstream. insn_get_length() has the side-effect of processing the entire instruction but only if it was decoded successfully, otherwise insn_complete() can fail and in this case we need to just return an error without warning. Reported-by: syzbot+30d675e3ca03c1c35...@syzkaller.appspotmail.com Signed-off-by: Oleg Nesterov <o...@redhat.com> Reviewed-by: Masami Hiramatsu <mhira...@kernel.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: syzkaller-b...@googlegroups.com Link: https://lkml.kernel.org/lkml/20180518162739.ga5...@redhat.com Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/x86/kernel/uprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -290,7 +290,7 @@ static int uprobe_init_insn(struct arch_ insn_init(insn, auprobe->insn, sizeof(auprobe->insn), x86_64); /* has the side-effect of processing the entire instruction */ insn_get_length(insn); - if (WARN_ON_ONCE(!insn_complete(insn))) + if (!insn_complete(insn)) return -ENOEXEC; if (is_prefix_bad(insn))
