umount: use devno to identify --all-target devices

 # mount -t tmpfs tmp /mnt/A
 # mount --bind /mnt/A /mnt/B
 # mount -t tmpfs tmp /mnt/C

the command:

  umount --all-targets /mnt/A

has to umount only A and B, but not C. The C is a another filesystem.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/sys-utils/umount.c b/sys-utils/umount.c
index e88320d651816296dae9e12758e9512b4ff716cd..17764b534f64e0b5cb978f42d314e7ec69a17897 100644 (file)
--- a/sys-utils/umount.c
+++ b/sys-utils/umount.c
@@ -406,7 +406,7 @@ static int umount_alltargets(struct libmnt_context *cxt, const char *spec, int r
        struct libmnt_fs *fs;
        struct libmnt_table *tb;
        struct libmnt_iter *itr = NULL;
-       char *src = NULL;
+       dev_t devno = 0;
        int rc;
 
        /* Convert @spec to device name, Use the same logic like regular
@@ -423,7 +423,7 @@ static int umount_alltargets(struct libmnt_context *cxt, const char *spec, int r
        if (rc < 0)
                return mk_exit_code(cxt, rc);           /* error */
 
-       if (!mnt_fs_get_srcpath(fs))
+       if (!mnt_fs_get_srcpath(fs) || !mnt_fs_get_devno(fs))
                err(MOUNT_EX_USAGE, _("%s: failed to determine source"), spec);
 
        itr = mnt_new_iter(MNT_ITER_BACKWARD);
@@ -437,13 +437,13 @@ static int umount_alltargets(struct libmnt_context *cxt, const char *spec, int r
 
        /* Note that @fs is from mount context and the context will be reseted
         * after each umount() call */
-       src = xstrdup(mnt_fs_get_srcpath(fs));
+       devno = mnt_fs_get_devno(fs);
        fs = NULL;
 
        mnt_reset_context(cxt);
 
        while (mnt_table_next_fs(tb, itr, &fs) == 0) {
-               if (!mnt_fs_streq_srcpath(fs, src))
+               if (mnt_fs_get_devno(fs) != devno)
                        continue;
                mnt_context_disable_swapmatch(cxt, 1);
                if (rec)
@@ -457,7 +457,6 @@ static int umount_alltargets(struct libmnt_context *cxt, const char *spec, int r
 
        mnt_free_iter(itr);
        mnt_free_table(tb);
-       free(src);
 
        return rc;
 }