X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=cmd%2Fmount_zfs%2Fmount_zfs.c;h=27a9014b3953894afd6e632892641d8ba09ac38b;hb=0c1171dcb5c50f3a03c60f4346209c23a2b5ef86;hp=6a2e9ff3647c856869f5bd0d7d4ad28c09253e33;hpb=2cf7f52bc42f215d4ef27d0fd75fc1b1417cb841;p=zfs.git

diff --git a/cmd/mount_zfs/mount_zfs.c b/cmd/mount_zfs/mount_zfs.c
index 6a2e9ff..27a9014 100644
--- a/cmd/mount_zfs/mount_zfs.c
+++ b/cmd/mount_zfs/mount_zfs.c
@@ -30,6 +30,7 @@
 #include <sys/mount.h>
 #include <sys/stat.h>
 #include <libzfs.h>
+#include <locale.h>
 #ifdef HAVE_LIBSELINUX
 #include <selinux/selinux.h>
 #endif /* HAVE_LIBSELINUX */
@@ -130,15 +131,6 @@ parse_option(char *mntopt, unsigned long *mntflags,
 		if (strncmp(name, opt->name, strlen(name)) == 0) {
 			*mntflags |= opt->mntmask;
 			*zfsflags |= opt->zfsmask;
-
-			/* MS_USERS implies default user options */
-			if (opt->mntmask & (MS_USERS))
-				*mntflags |= (MS_NOEXEC|MS_NOSUID|MS_NODEV);
-
-			/* MS_OWNER|MS_GROUP imply default owner options */
-			if (opt->mntmask & (MS_OWNER | MS_GROUP))
-				*mntflags |= (MS_NOSUID|MS_NODEV);
-
 			error = 0;
 			goto out;
 		}
@@ -219,17 +211,55 @@ out:
 }
 
 /*
- * If a file or directory in your current working directory is named
- * 'dataset' then mount(8) will prepend your current working directory
- * to dataset.  The is no way to prevent this behavior so we simply
- * check for it and strip the prepended patch when it is added.
+ * Return the pool/dataset to mount given the name passed to mount.  This
+ * is expected to be of the form pool/dataset, however may also refer to
+ * a block device if that device contains a valid zfs label.
  */
 static char *
 parse_dataset(char *dataset)
 {
 	char cwd[PATH_MAX];
+	struct stat64 statbuf;
+	int error;
 	int len;
 
+	/*
+	 * We expect a pool/dataset to be provided, however if we're
+	 * given a device which is a member of a zpool we attempt to
+	 * extract the pool name stored in the label.  Given the pool
+	 * name we can mount the root dataset.
+	 */
+	error = stat64(dataset, &statbuf);
+	if (error == 0) {
+		nvlist_t *config;
+		char *name;
+		int fd;
+
+		fd = open(dataset, O_RDONLY);
+		if (fd < 0)
+			goto out;
+
+		error = zpool_read_label(fd, &config);
+		(void) close(fd);
+		if (error)
+			goto out;
+
+		error = nvlist_lookup_string(config,
+		    ZPOOL_CONFIG_POOL_NAME, &name);
+		if (error == 0)
+			dataset = strdup(name);
+
+		nvlist_free(config);
+		return (dataset);
+	}
+out:
+	/*
+	 * If a file or directory in your current working directory is
+	 * named 'dataset' then mount(8) will prepend your current working
+	 * directory to the dataset.  There is no way to prevent this
+	 * behavior so we simply check for it and strip the prepended
+	 * patch when it is added.
+	 */
 	if (getcwd(cwd, PATH_MAX) == NULL)
 		return (dataset);
 
@@ -310,8 +340,9 @@ main(int argc, char **argv)
 	char mntopts[MNT_LINE_MAX] = { '\0' };
 	char badopt[MNT_LINE_MAX] = { '\0' };
 	char mtabopt[MNT_LINE_MAX] = { '\0' };
-	char *dataset, *mntpoint;
-	unsigned long mntflags = 0, zfsflags = 0, remount_ro = 0;
+	char mntpoint[PATH_MAX];
+	char *dataset;
+	unsigned long mntflags = 0, zfsflags = 0, remount = 0;
 	int sloppy = 0, fake = 0, verbose = 0, nomtab = 0, zfsutil = 0;
 	int error, c;
 
@@ -366,7 +397,14 @@ main(int argc, char **argv)
 	}
 
 	dataset = parse_dataset(argv[0]);
-	mntpoint = argv[1];
+
+	/* canonicalize the mount point */
+	if (realpath(argv[1], mntpoint) == NULL) {
+		(void) fprintf(stderr, gettext("filesystem '%s' cannot be "
+		    "mounted at '%s' due to canonicalization error %d.\n"),
+		    dataset, argv[1], errno);
+		return (MOUNT_SYSERR);
+	}
 
 	/* validate mount options and set mntflags */
 	error = parse_options(mntopts, &mntflags, &zfsflags, sloppy,
@@ -416,11 +454,10 @@ main(int argc, char **argv)
 		    "  mountopts:  \"%s\"\n  mtabopts:   \"%s\"\n"),
 		    dataset, mntpoint, mntflags, zfsflags, mntopts, mtabopt);
 
-	if (mntflags & MS_REMOUNT)
+	if (mntflags & MS_REMOUNT) {
 		nomtab = 1;
-
-	if ((mntflags & MS_REMOUNT) && (mntflags & MS_RDONLY))
-		remount_ro = 1;
+		remount = 1;
+	}
 
 	if (zfsflags & ZS_ZFSUTIL)
 		zfsutil = 1;
@@ -453,9 +490,10 @@ main(int argc, char **argv)
 	 * we differentiate the two cases using the 'zfsutil' mount option.
 	 * This mount option should only be supplied by the 'zfs mount' util.
 	 *
-	 * The only exception to the above rule is '-o remount,ro'.  This is
-	 * always allowed for non-legacy datasets for rc.sysinit/umountroot
-	 * to safely remount the root filesystem and flush its cache.
+	 * The only exception to the above rule is '-o remount' which is
+	 * always allowed for non-legacy datasets.  This is done because when
+	 * using zfs as your root file system both rc.sysinit/umountroot and
+	 * systemd depend on 'mount -o remount <mountpoint>' to work.
 	 */
 	if (zfsutil && !strcmp(legacy, ZFS_MOUNTPOINT_LEGACY)) {
 		(void) fprintf(stderr, gettext(
@@ -466,7 +504,8 @@ main(int argc, char **argv)
 		return (MOUNT_USAGE);
 	}
 
-	if (!zfsutil && strcmp(legacy, ZFS_MOUNTPOINT_LEGACY) && !remount_ro) {
+	if (!zfsutil && !(remount || fake) &&
+	    strcmp(legacy, ZFS_MOUNTPOINT_LEGACY)) {
 		(void) fprintf(stderr, gettext(
 		    "filesystem '%s' cannot be mounted using 'mount'.\n"
 		    "Use 'zfs set mountpoint=%s' or 'zfs mount %s'.\n"
@@ -480,6 +519,10 @@ main(int argc, char **argv)
 		    mntflags, mntopts);
 		if (error) {
 			switch (errno) {
+			case ENOENT:
+				(void) fprintf(stderr, gettext("mount point "
+				    "'%s' does not exist\n"), mntpoint);
+				return (MOUNT_SYSERR);
 			case EBUSY:
 				(void) fprintf(stderr, gettext("filesystem "
 				    "'%s' is already mounted\n"), dataset);