From 616025d845b6789a71d475ef43cd71dad631d2e0 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 14 Feb 2019 11:08:49 +0800 Subject: [PATCH] signal: Properly deliver SIGILL from uprobes mainline inclusion from mainline-4.20 commit 55a3235fc71b category: bugfix bugzilla: 5741 CVE: NA ------------------------------------------------- For userspace to tell the difference between a random signal and an exception, the exception must include siginfo information. Using SEND_SIG_FORCED for SIGILL is thus wrong, and it will result in userspace seeing si_code == SI_USER (like a random signal) instead of si_code == SI_KERNEL or a more specific si_code as all exceptions deliver. Therefore replace force_sig_info(SIGILL, SEND_SIG_FORCE, current) with force_sig(SIG_ILL, current) which gets this right and is shorter and easier to type. Fixes: 014940bad8e4 ("uprobes/x86: Send SIGILL if arch_uprobe_post_xol() fails") Fixes: 0b5256c7f173 ("uprobes: Send SIGILL if handle_trampoline() fails") Reviewed-by: Thomas Gleixner Signed-off-by: "Eric W. Biederman" (cherry picked from commit 55a3235fc71bf34303e34a95eeee235b2d2a35dd) Signed-off-by: Xie XiuQi Reviewed-by: Cheng Jian Signed-off-by: Yang Yingliang --- kernel/events/uprobes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 578d4ac54484..c173e4131df8 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1858,7 +1858,7 @@ static void handle_trampoline(struct pt_regs *regs) sigill: uprobe_warn(current, "handle uretprobe, sending SIGILL."); - force_sig_info(SIGILL, SEND_SIG_FORCED, current); + force_sig(SIGILL, current); } @@ -1974,7 +1974,7 @@ static void handle_singlestep(struct uprobe_task *utask, struct pt_regs *regs) if (unlikely(err)) { uprobe_warn(current, "execute the probed insn, sending SIGILL."); - force_sig_info(SIGILL, SEND_SIG_FORCED, current); + force_sig(SIGILL, current); } } -- GitLab