From c2f5a837b8e5153521384fff5e1c9cab2cf37d8f Mon Sep 17 00:00:00 2001 From: "shess@chromium.org" Date: Wed, 27 Feb 2013 00:53:01 +0000 Subject: [PATCH] [Mac] Do not forward graceful shutdown from child signal handlers. OSX implements fork() as a userland wrapper around a system call. If a graceful-shutdown signal is received before the graceful-shutdown pipe has been replaced, the parent process will shutdown. Change to force a crash in the child in this case. BUG=175341 Review URL: https://codereview.chromium.org/12314106 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@184805 0039d316-1c4b-4281-b951-d872f2087c98 --- chrome/browser/chrome_browser_main_posix.cc | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/chrome/browser/chrome_browser_main_posix.cc b/chrome/browser/chrome_browser_main_posix.cc index 1bb0f2c822d4..cb83f97beaf0 100644 --- a/chrome/browser/chrome_browser_main_posix.cc +++ b/chrome/browser/chrome_browser_main_posix.cc @@ -40,6 +40,13 @@ namespace { void SIGCHLDHandler(int signal) { } +// The OSX fork() implementation can crash in the child process before +// fork() returns. In that case, the shutdown pipe will still be +// shared with the parent process. To prevent child crashes from +// causing parent shutdowns, |g_pipe_pid| is the pid for the process +// which registered |g_shutdown_pipe_write_fd|. +// See . +pid_t g_pipe_pid = -1; int g_shutdown_pipe_write_fd = -1; int g_shutdown_pipe_read_fd = -1; @@ -51,6 +58,7 @@ void GracefulShutdownHandler(int signal) { action.sa_handler = SIG_DFL; RAW_CHECK(sigaction(signal, &action, NULL) == 0); + RAW_CHECK(g_pipe_pid == getpid()); RAW_CHECK(g_shutdown_pipe_write_fd != -1); RAW_CHECK(g_shutdown_pipe_read_fd != -1); size_t bytes_written = 0; @@ -299,6 +307,7 @@ void ChromeBrowserMainPartsPosix::PostMainMessageLoopStart() { if (ret < 0) { PLOG(DFATAL) << "Failed to create pipe"; } else { + g_pipe_pid = getpid(); g_shutdown_pipe_read_fd = pipefd[0]; g_shutdown_pipe_write_fd = pipefd[1]; #if !defined(ADDRESS_SANITIZER) && !defined(KEEP_SHADOW_STACKS) -- 2.11.4.GIT