umount.nfs: fix nfs4 check

From: Ian Kent <ikent@redhat.com>

nfs_umount_is_vers4() doesn't take acount of the escaping of characters
seen in /proc/mounts and /etc/mtab as the functions in fstab.c do. This
leads to an inability to umount a mount containing any of these escaped
characters (like spaces).

This patch changes nfs_umount_is_vers4() to use functions in fstab.c and
adds a function to fstab.c to read /proc/mounts specifically, as it was
used  for the check in nfs_umount_is_vers4() previously.

Signed-off-by: Ian Kent <ikent@redhat.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/utils/mount/fstab.c b/utils/mount/fstab.c
index 1fc9efe8e24410152c171b5a279c6cbb077565fb..eedbddab87c63e3ea99c2a8507d7028c0d6cc2b5 100644 (file)
--- a/utils/mount/fstab.c
+++ b/utils/mount/fstab.c
@@ -86,10 +86,13 @@ mtab_is_writable() {
 
 struct mntentchn mounttable;
 static int got_mtab = 0;
+struct mntentchn procmounts;
+static int got_procmounts = 0;
 struct mntentchn fstab;
 static int got_fstab = 0;
 
 static void read_mounttable(void);
+static void read_procmounts(void);
 static void read_fstab(void);
 
 static struct mntentchn *
@@ -100,6 +103,14 @@ mtab_head(void)
        return &mounttable;
 }
 
+static struct mntentchn *
+procmounts_head(void)
+{
+       if (!got_procmounts)
+               read_procmounts();
+       return &procmounts;
+}
+
 static struct mntentchn *
 fstab_head(void)
 {
@@ -186,6 +197,30 @@ read_mounttable() {
         read_mntentchn(mfp, fnam, mc);
 }
 
+/*
+ * Read /proc/mounts.
+ * This produces a linked list. The list head procmounts is a dummy.
+ * Return 0 on success.
+ */
+static void
+read_procmounts() {
+        mntFILE *mfp;
+        const char *fnam;
+        struct mntentchn *mc = &procmounts;
+
+        got_procmounts = 1;
+        mc->nxt = mc->prev = NULL;
+
+        fnam = PROC_MOUNTS;
+        mfp = nfs_setmntent(fnam, "r");
+        if (mfp == NULL || mfp->mntent_fp == NULL) {
+                nfs_error(_("warning: can't open %s: %s"),
+                          PROC_MOUNTS, strerror (errno));
+                return;
+        }
+        read_mntentchn(mfp, fnam, mc);
+}
+
 static void
 read_fstab()
 {
@@ -224,6 +259,23 @@ getmntdirbackward (const char *name, struct mntentchn *mcprev) {
        return NULL;
 }
 
+/*
+ * Given the directory name NAME, and the place MCPREV we found it last time,
+ * try to find more occurrences.
+ */
+struct mntentchn *
+getprocmntdirbackward (const char *name, struct mntentchn *mcprev) {
+       struct mntentchn *mc, *mc0;
+
+       mc0 = procmounts_head();
+       if (!mcprev)
+               mcprev = mc0;
+       for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev)
+               if (streq(mc->m.mnt_dir, name))
+                       return mc;
+       return NULL;
+}
+
 /*
  * Given the device name NAME, and the place MCPREV we found it last time,
  * try to find more occurrences.

diff --git a/utils/mount/fstab.h b/utils/mount/fstab.h
index dc7c9fc8d73bdc854e78c5c87a68dbb76e71445d..313bf9b3bd9f00d4ae63deb722b341521bcdff89 100644 (file)
--- a/utils/mount/fstab.h
+++ b/utils/mount/fstab.h
@@ -18,6 +18,7 @@ struct mntentchn {
 
 struct mntentchn *getmntoptfile (const char *file);
 struct mntentchn *getmntdirbackward (const char *dir, struct mntentchn *mc);
+struct mntentchn *getprocmntdirbackward (const char *name, struct mntentchn *mc);
 struct mntentchn *getmntdevbackward (const char *dev, struct mntentchn *mc);
 
 struct mntentchn *getfsfile (const char *file);

diff --git a/utils/mount/nfsumount.c b/utils/mount/nfsumount.c
index 8cd28528b1a01d4c4b86b3306189088b6a927d2a..b846564a331e41da2c178f2cf280b84eded197ab 100644 (file)
--- a/utils/mount/nfsumount.c
+++ b/utils/mount/nfsumount.c
@@ -151,65 +151,50 @@ static int del_mtab(const char *spec, const char *node)
  */
 static int nfs_umount_is_vers4(const struct mntentchn *mc)
 {
-       char buffer[LINELEN], *next;
+       struct mntentchn *pmc;
+       struct mount_options *options;
        int retval;
-       FILE *f;
-
-       if ((f = fopen(MOUNTSFILE, "r")) == NULL) {
-               fprintf(stderr, "%s: %s\n",
-                       MOUNTSFILE, strerror(errno));
-               return -1;
-       }
 
        retval = -1;
-       while (fgets(buffer, sizeof(buffer), f) != NULL) {
-               char *device, *mntdir, *type, *flags;
-               struct mount_options *options;
-               char *line = buffer;
-
-               next = strchr(line, '\n');
-               if (next != NULL)
-                       *next = '\0';
-
-               device = strtok(line, " \t");
-               if (device == NULL)
-                       continue;
-               mntdir = strtok(NULL, " \t");
-               if (mntdir == NULL)
-                       continue;
-               if (strcmp(device, mc->m.mnt_fsname) != 0 &&
-                   strcmp(mntdir, mc->m.mnt_dir) != 0)
+       pmc = getprocmntdirbackward(mc->m.mnt_dir, NULL);
+       if (!pmc)
+               goto not_found;
+
+       do {
+               int nlen = strlen(pmc->m.mnt_fsname);
+               /*
+                * It's possible the mount location string in /proc/mounts
+                * ends with a '/'. In this case, if the entry came from
+                * /etc/mtab, it won't have the trailing '/' so deal with
+                * it.
+                */
+               while (pmc->m.mnt_fsname[nlen - 1] == '/')
+                       nlen--;
+               if (strncmp(pmc->m.mnt_fsname, mc->m.mnt_fsname, nlen) != 0)
                        continue;
 
-               type = strtok(NULL, " \t");
-               if (type == NULL)
-                       continue;
-               if (strcmp(type, "nfs4") == 0)
+               if (strcmp(pmc->m.mnt_type, "nfs4") == 0)
                        goto out_nfs4;
 
-               flags = strtok(NULL, " \t");
-               if (flags == NULL)
-                       continue;
-               options = po_split(flags);
+               options = po_split(pmc->m.mnt_opts);
                if (options != NULL) {
                        unsigned long version;
-                       int rc;
-
-                       rc = nfs_nfs_version(options, &version);
+                       int rc = nfs_nfs_version(options, &version);
                        po_destroy(options);
                        if (rc && version == 4)
                                goto out_nfs4;
                }
 
-               goto out_nfs;
-       }
-       if (retval == -1)
+               if (strcmp(pmc->m.mnt_type, "nfs") == 0)
+                       goto out_nfs;
+       } while ((pmc = getprocmntdirbackward(mc->m.mnt_dir, pmc)) != NULL);
+
+       if (retval == -1) {
+not_found:
                fprintf(stderr, "%s was not found in %s\n",
                        mc->m.mnt_dir, MOUNTSFILE);
-
-out:
-       fclose(f);
-       return retval;
+               goto out;
+       }
 
 out_nfs4:
        if (verbose)
@@ -221,7 +206,9 @@ out_nfs:
        if (verbose)
                fprintf(stderr, "Legacy NFS mount point detected\n");
        retval = 0;
-       goto out;
+
+out:
+       return retval;
 }
 
 static struct option umount_longopts[] =