From 0032322689bb5fbf480e7de18488d0c0659cb129 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Fri, 18 May 2018 18:27:39 +0200 Subject: [PATCH] uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn() 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+30d675e3ca03c1c351e7@syzkaller.appspotmail.com Signed-off-by: Oleg Nesterov Reviewed-by: Masami Hiramatsu Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: syzkaller-bugs@googlegroups.com Link: https://lkml.kernel.org/lkml/20180518162739.GA5559@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/uprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index e1ea13ae53b9..b9a8f34b5e5a 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -290,7 +290,7 @@ static int uprobe_init_insn(struct arch_uprobe *auprobe, struct insn *insn, bool 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)) -- 2.20.1