From 473c34f895c49bf2bd327ece586d3613cd86c068 Mon Sep 17 00:00:00 2001 From: Emmanuel Dreyfus Date: Sun, 21 Sep 2014 13:57:47 +0200 Subject: Do not hardcode umount(8) path, emulate lazy umount 1) Use a system-dependent macro for umount(8) location instead of relying on $PATH to find it, for security and portability sake. 2) Introduce gf_umount_lazy() to replace umount -l (-l for lazy) invocations, which is only supported on Linux; On Linux behavior in unchanged. On other systems, we fork an external process (umountd) that will take care of periodically attempt to unmount, and optionally rmdir. BUG: 1129939 Change-Id: Ia91167c0652f8ddab85136324b08f87c5ac1e51d Signed-off-by: Emmanuel Dreyfus Reviewed-on: http://review.gluster.org/8649 Tested-by: Gluster Build System Reviewed-by: Csaba Henk Reviewed-by: Vijay Bellur --- contrib/umountd/Makefile.am | 10 ++ contrib/umountd/umountd.c | 247 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 257 insertions(+) create mode 100644 contrib/umountd/Makefile.am create mode 100644 contrib/umountd/umountd.c (limited to 'contrib') diff --git a/contrib/umountd/Makefile.am b/contrib/umountd/Makefile.am new file mode 100644 index 00000000000..c03b0cbcae6 --- /dev/null +++ b/contrib/umountd/Makefile.am @@ -0,0 +1,10 @@ +sbin_PROGRAMS = umountd +umountd_SOURCES = umountd.c +umountd_CFLAGS = $(GF_CFLAGS) -DDATADIR=\"$(localstatedir)\" +umountd_LDADD = $(top_builddir)/libglusterfs/src/libglusterfs.la ${GF_LDADD} +umountd_LDFLAGS = $(GF_LDFLAGS) + +AM_CPPFLAGS = $(GF_CPPFLAGS) -I$(top_srcdir)/libglusterfs/src +AM_CFLAGS = -Wall $(GF_CFLAGS) + +CLEANFILES = diff --git a/contrib/umountd/umountd.c b/contrib/umountd/umountd.c new file mode 100644 index 00000000000..42f867d1983 --- /dev/null +++ b/contrib/umountd/umountd.c @@ -0,0 +1,247 @@ +/* + Copyright (c) 2008-2012 Red Hat, Inc. + This file is part of GlusterFS. + + This file is licensed to you under your choice of the GNU Lesser + General Public License, version 3 or any later version (LGPLv3 or + later), or the GNU General Public License, version 2 (GPLv2), in all + cases as published by the Free Software Foundation. +*/ + +#ifndef _CONFIG_H +#define _CONFIG_H +#include "config.h" +#endif + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "glusterfs.h" +#include "globals.h" +#include "logging.h" +#include "syscall.h" +#include "mem-types.h" + +static void +usage (void) +{ + fprintf (stderr, "Usage: umountd [-d dev] [-t timeout] [-r] path\n"); + exit (EXIT_FAILURE); +} + + +static int +sanity_check (char *path, dev_t *devp) +{ + struct stat st; + struct stat parent_st; + int ret; + char pathtmp[PATH_MAX]; + char *parent; + + if (path == NULL) + usage (); + + if (stat (path, &st) != 0) { + gf_log ("umountd", GF_LOG_ERROR, + "Cannot access %s\n", path, strerror (errno)); + goto out; + } + + /* If dev was not specified, get it from path */ + if (*devp == -1) + *devp = st.st_dev; + + strncpy (pathtmp, path, PATH_MAX); + parent = dirname (pathtmp); + + if (stat (parent, &parent_st) != 0) { + gf_log ("umountd", GF_LOG_ERROR, + "Cannot access %s\n", parent, strerror (errno)); + goto out; + } + + if (st.st_dev == parent_st.st_dev) { + gf_log ("umountd", GF_LOG_ERROR, + "No filesystem mounted on %s\n", path); + goto out; + } + + ret = 0; + +out: + return ret; +} + +static void +log_rotate (int signum) +{ + gf_log_logrotate (1); + + if (signal (SIGHUP, *log_rotate) == SIG_ERR) { + gf_log ("umountd", GF_LOG_ERROR, "signal () failed"); + exit (EXIT_FAILURE); + } + + return; +} + +static int +logging_init (void) +{ + glusterfs_ctx_t *ctx; + char log_file[PATH_MAX]; + int ret = -1; + + ctx = glusterfs_ctx_new (); + if (!ctx) { + fprintf (stderr, "glusterfs_ctx_new failed\n"); + goto out; + } + + ret = glusterfs_globals_init (ctx); + if (ret) { + fprintf (stderr, "glusterfs_globals_init failed\n"); + goto out; + } + + THIS->ctx = ctx; + xlator_mem_acct_init (THIS, gf_common_mt_end); + + snprintf (log_file, PATH_MAX, + "%s/umountd.log", DEFAULT_LOG_FILE_DIRECTORY); + + ret = gf_log_init (ctx, log_file, "umountd"); + if (ret) { + fprintf (stderr, "gf_log_init failed\n"); + goto out; + } + + if (signal (SIGHUP, *log_rotate) == SIG_ERR) { + gf_log ("umountd", GF_LOG_ERROR, "signal () failed"); + goto out; + } + + ret = 0; +out: + return ret; +} + +static int +umountd_async (char *path, dev_t dev, int frmdir, int timeout) +{ + int ret = -1; + struct stat stbuf = {0, }; + int unmount_ret = 0; + + do { + unmount_ret = unmount (path, 0); + if (unmount_ret == 0) + gf_log ("umountd", GF_LOG_INFO, "Unmounted %s", path); + + if (unmount_ret != 0 && errno != EBUSY) { + gf_log ("umountd", GF_LOG_WARNING, + "umount %s failed: %s", + path, strerror (errno)); + } + + ret = sys_lstat (path, &stbuf); + if (ret != 0) { + gf_log ("umountd", GF_LOG_WARNING, + "Cannot stat device from %s", + path, strerror (errno)); + break; + } + + if (stbuf.st_dev != dev) { + if (unmount_ret != 0) + gf_log ("umountd", GF_LOG_INFO, + "device mismatch " + "(expect %lld, found %lld), " + "someone else unmounted %s", + dev, stbuf.st_dev, path); + ret = 0; + break; + } + + sleep (timeout); + } while (1/*CONSTCOND*/); + + if (ret) { + gf_log ("umountd", GF_LOG_ERROR, + "Asynchronous unmount of %s failed: %s", + path, strerror (errno)); + } else { + if (frmdir) { + ret = rmdir (path); + if (ret) + gf_log ("umountd", GF_LOG_WARNING, + "rmdir %s failed: %s", + path, strerror (errno)); + else + gf_log ("umountd", GF_LOG_INFO, + "Removed %s", path); + } + } + + return ret; +} + +int +main (int argc, char **argv) +{ + char *path = NULL; + dev_t dev = -1; + int frmdir = 0; + int timeout = 30; + int f; + + while ((f = getopt (argc, argv, "d:rt:")) != -1) { + switch (f) { + case 'p': + path = optarg; + break; + case 'd': + dev = strtoll (optarg, NULL, 10); + break; + case 't': + timeout = atoi (optarg); + break; + case 'r': + frmdir = 1; + break; + default: + usage (); + break; + } + } + + argc -= optind; + argv += optind; + + if (argc != 1) + usage (); + + path = argv[0]; + + if (logging_init () != 0) + exit (EXIT_FAILURE); + + if (sanity_check (path, &dev) != 0) + exit (EXIT_FAILURE); + + if (daemon (0, 0) != 0) + exit (EXIT_FAILURE); + + if (umountd_async (path, dev, frmdir, timeout) != 0) + exit (EXIT_FAILURE); + + return EXIT_SUCCESS; +} -- cgit