From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx.aristanetworks.com ([162.210.129.12]:52618 "EHLO prod-mx.aristanetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727010AbeGaCdx (ORCPT ); Mon, 30 Jul 2018 22:33:53 -0400 Date: Mon, 30 Jul 2018 17:56:15 -0700 From: Ivan Delalande To: Al Viro Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH RESEND] exec: don't force_sigsegv processes with a pending fatal signal Message-ID: <20180731005615.GA2911@visor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-ID: We were seeing unexplained segfaults in coreutils processes and other basic utilities that we tracked down to binfmt_elf failing to load segments for ld.so. Digging further, the actual problem seems to occur when a process gets sigkilled while it is still being loaded by the kernel. In our case when _do_page_fault goes for a retry it will return early as it first checks for fatal_signal_pending(), so load_elf_interp also returns with error and as a result search_binary_handler will force_sigsegv() which is pretty confusing as nothing actually failed here. Fixes: 19d860a140be ("handle suicide on late failure exits in execve() in search_binary_handler()") Reference: https://lkml.org/lkml/2013/2/14/5 Signed-off-by: Ivan Delalande --- fs/exec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/exec.c b/fs/exec.c index bdd0eacefdf5..6e8007edbb2d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1656,7 +1656,8 @@ int search_binary_handler(struct linux_binprm *bprm) if (retval < 0 && !bprm->mm) { /* we got to flush_old_exec() and failed after it */ read_unlock(&binfmt_lock); - force_sigsegv(SIGSEGV, current); + if (!fatal_signal_pending(current)) + force_sigsegv(SIGSEGV, current); return retval; } if (retval != -ENOEXEC || !bprm->file) { -- 2.18.0